Liberty Property Limited Partnership 10-K 27 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2018	Feb. 19, 2019	Jun. 30, 2018
Document Information [Line Items]
Entity Registrant Name	LIBERTY PROPERTY TRUST
Entity Central Index Key	921,112
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		147,952,588
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Public Float			$ 6.5
Liberty Property Limited Partnership
Document Information [Line Items]
Entity Registrant Name	LIBERTY PROPERTY LIMITED PARTNERSHIP
Entity Central Index Key	921,113

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Real estate:
Land and land improvements	$ 1,256,706	$ 1,023,553
Building and improvements	4,655,784	4,113,163
Less accumulated depreciation	(974,972)	(851,624)
Operating real estate	4,937,518	4,285,092
Development in progress	472,169	333,437
Land held for development	296,244	330,748
Net real estate	5,705,931	4,949,277
Cash and cash equivalents	84,923	11,882
Restricted cash	10,899	13,803
Accounts receivable, net	14,217	10,373
Deferred rent receivable, net	125,291	106,257
Deferred financing and leasing costs, net	168,739	147,455
Investments in and advances to unconsolidated joint ventures	350,981	288,456
Assets held for sale	220,545	622,575
Prepaid expenses and other assets	252,868	289,679
Total assets	6,934,394	6,439,757
LIABILITIES
Mortgage loans, net	395,202	267,093
Unsecured notes, net	2,285,698	2,283,513
Credit facilities	411,846	358,939
Accounts payable	65,591	76,077
Accrued interest	22,309	21,796
Dividend and distributions payable	60,560	60,330
Other liabilities	285,696	201,483
Liabilities held for sale	3,183	14,623
Total liabilities	3,530,085	3,283,854
Noncontrolling interest - operating partnership - 301,483 preferred units outstanding as of December 31, 2018 and December 31, 2017	7,537	7,537
EQUITY
Common shares of beneficial interest, $.001 par value, 283,987,000 shares authorized; 147,899,354 and 147,450,691 shares issued and outstanding as of December 31, 2018 and December 31, 2017, respectively	148	147
Additional paid-in capital	3,691,778	3,674,978
Accumulated other comprehensive loss	(55,243)	(37,797)
Distributions in excess of net income	(306,822)	(549,970)
Total Liberty Property Trust shareholders’ equity	3,329,861	3,087,358
Noncontrolling interest – operating partnership
Noncontrolling interest – operating partnership - 3,520,205 common units outstanding as of December 31, 2018 and December 31, 2017	61,471	56,159
Noncontrolling interest – consolidated joint ventures	5,440	4,849
Total equity	3,396,772	3,148,366
Total liabilities, noncontrolling interest - operating partnership and equity	6,934,394	6,439,757
Liberty Property Limited Partnership
Real estate:
Land and land improvements	1,256,706	1,023,553
Building and improvements	4,655,784	4,113,163
Less accumulated depreciation	(974,972)	(851,624)
Operating real estate	4,937,518	4,285,092
Development in progress	472,169	333,437
Land held for development	296,244	330,748
Net real estate	5,705,931	4,949,277
Cash and cash equivalents	84,923	11,882
Restricted cash	10,899	13,803
Accounts receivable, net	14,217	10,373
Deferred rent receivable, net	125,291	106,257
Deferred financing and leasing costs, net	168,739	147,455
Investments in and advances to unconsolidated joint ventures	350,981	288,456
Assets held for sale	220,545	622,575
Prepaid expenses and other assets	252,868	289,679
Total assets	6,934,394	6,439,757
LIABILITIES
Mortgage loans, net	395,202	267,093
Unsecured notes, net	2,285,698	2,283,513
Credit facilities	411,846	358,939
Accounts payable	65,591	76,077
Accrued interest	22,309	21,796
Dividend and distributions payable	60,560	60,330
Other liabilities	285,696	201,483
Liabilities held for sale	3,183	14,623
Total liabilities	3,530,085	3,283,854
Noncontrolling interest - operating partnership - 301,483 preferred units outstanding as of December 31, 2018 and December 31, 2017	7,537	7,537
EQUITY
General partner’s equity - 147,899,354 and 147,450,691 common units outstanding as of December 31, 2018 and December 31, 2017, respectively	3,329,861	3,087,358
Limited partners’ equity – 3,520,205 common units outstanding as of December 31, 2018 and December 31, 2017	61,471	56,159
Noncontrolling interest – operating partnership
Noncontrolling interest – consolidated joint ventures	5,440	4,849
Total equity	3,396,772	3,148,366
Total liabilities, noncontrolling interest - operating partnership and equity	$ 6,934,394	$ 6,439,757

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Par value (USD per share)	$ 0.001	$ 0.001
Common shares authorized (in shares)	283,987,000	283,987,000
Common shares issued (in shares)	147,899,354	147,450,691
Common shares outstanding (in shares)	147,899,354	147,450,691
Common units outstanding (in shares)	3,520,205	3,520,205
Redeemable Preferred Stock
Redeemable stock, preferred units outstanding (in shares)	301,483	301,483
Liberty Property Limited Partnership
General Partners' Capital Account, Units Outstanding	147,899,354	147,450,691
Common units outstanding (in shares)	3,520,205	3,520,205
Liberty Property Limited Partnership | Redeemable Preferred Stock
Redeemable stock, preferred units outstanding (in shares)	301,483	301,483

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
REVENUE
Rental	$ 480,389	$ 446,527	$ 495,067
Operating expense reimbursement	151,276	136,184	167,315
Development service fee income	73,224	82,673	12,941
Total revenue	704,889	665,384	675,323
EXPENSE
Rental property	62,301	57,614	88,698
Real estate taxes	91,663	83,152	92,920
General and administrative	53,843	56,191	63,071
Other operating expense	11,994	6,167	5,017
Interest expense	89,630	84,238	105,127
Loss on debt extinguishment	0	49	27,099
Depreciation and amortization	169,717	162,700	191,448
Development service fee expense	134,825	85,805	12,165
Impairment - real estate assets	32,431	3,946	3,879
Total expense	646,404	539,862	589,424
Interest and other income	12,048	7,734	13,846
Gain on property dispositions	81,514	100,387	219,270
Income taxes	(7,364)	(1,992)	(1,969)
Equity in earnings of unconsolidated joint ventures	21,382	17,155	21,970
Income from continuing operations	166,065	248,806	339,016
Discontinued operations (including net gain of $303.2 million and $14.6 million on property dispositions for the years ended December 31, 2018 and 2017, respectively)	326,538	41,239	27,129
Net income	492,603	290,045	366,145
Noncontrolling interest – operating partnership	(11,886)	(7,224)	(9,070)
Noncontrolling interest – consolidated joint ventures	(1,110)	(481)	(258)
Income available to common shareholders	479,607	282,340	356,817
Comprehensive income attributable to common shareholders
Net income	492,603	290,045	366,145
Other comprehensive (loss) income - foreign currency translation	(14,161)	18,066	(34,744)
Other comprehensive (loss) income - derivative instruments	(3,700)	605	410
Other comprehensive (loss) income	(17,861)	18,671	(34,334)
Total comprehensive income	474,742	308,716	331,811
Less: comprehensive income attributable to noncontrolling interest	(12,581)	(8,142)	(8,519)
Comprehensive income attributable to common shareholders	$ 462,161	$ 300,574	$ 323,292
Basic:
Income from continuing operations (USD per share/unit)	$ 1.09	$ 1.65	$ 2.26
Income from discontinued operations (USD per share/unit)	2.17	0.27	0.18
Income per common share - basic (USD per share/unit)	3.26	1.92	2.44
Diluted:
Income from continuing operations (USD per share/unit)	1.09	1.64	2.25
Income from discontinued operations (USD per share/unit)	2.15	0.27	0.18
Income per common share - diluted (USD per share/unit)	$ 3.24	$ 1.91	$ 2.43
Weighted average number of common shares outstanding
Basic (shares)	147,275	146,742	146,204
Diluted (shares)	148,221	147,541	146,889
Amounts attributable to common shareholders
Income from continuing operations	$ 160,677	$ 242,066	$ 330,320
Discontinued operations	318,930	40,274	26,497
Income available to common shareholders	479,607	282,340	356,817
Liberty Property Limited Partnership
REVENUE
Rental	480,389	446,527	495,067
Operating expense reimbursement	151,276	136,184	167,315
Development service fee income	73,224	82,673	12,941
Total revenue	704,889	665,384	675,323
EXPENSE
Rental property	62,301	57,614	88,698
Real estate taxes	91,663	83,152	92,920
General and administrative	53,843	56,191	63,071
Other operating expense	11,994	6,167	5,017
Interest expense	89,630	84,238	105,127
Loss on debt extinguishment	0	49	27,099
Depreciation and amortization	169,717	162,700	191,448
Development service fee expense	134,825	85,805	12,165
Impairment - real estate assets	32,431	3,946	3,879
Total expense	646,404	539,862	589,424
Interest and other income	12,048	7,734	13,846
Gain on property dispositions	81,514	100,387	219,270
Income taxes	(7,364)	(1,992)	(1,969)
Equity in earnings of unconsolidated joint ventures	21,382	17,155	21,970
Income from continuing operations	166,065	248,806	339,016
Discontinued operations (including net gain of $303.2 million and $14.6 million on property dispositions for the years ended December 31, 2018 and 2017, respectively)	326,538	41,239	27,129
Net income	492,603	290,045	366,145
Noncontrolling interest – consolidated joint ventures	(1,110)	(481)	(258)
Preferred unit distributions	(472)	(472)	(472)
Income available to common shareholders	491,021	289,092	365,415
Comprehensive income attributable to common shareholders
Net income	492,603	290,045	366,145
Other comprehensive (loss) income - foreign currency translation	(14,161)	18,066	(34,744)
Other comprehensive (loss) income - derivative instruments	(3,700)	605	410
Other comprehensive (loss) income	(17,861)	18,671	(34,334)
Total comprehensive income	$ 474,742	$ 308,716	$ 331,811
Basic:
Income from continuing operations (USD per share/unit)	$ 1.09	$ 1.65	$ 2.26
Income from discontinued operations (USD per share/unit)	2.17	0.27	0.18
Income per common share - basic (USD per share/unit)	3.26	1.92	2.44
Diluted:
Income from continuing operations (USD per share/unit)	1.09	1.64	2.25
Income from discontinued operations (USD per share/unit)	2.15	0.27	0.18
Income per common share - diluted (USD per share/unit)	$ 3.24	$ 1.91	$ 2.43
Weighted average number of common shares outstanding
Basic (shares)	150,795	150,270	149,740
Diluted (shares)	151,741	151,069	150,425
Amounts attributable to common shareholders
Income from continuing operations	$ 164,955	$ 248,325	$ 338,758
Discontinued operations	326,538	41,239
Income available to common shareholders	491,021	289,092	365,415
Net income allocated to general partners	479,607	282,340	356,817
Net income allocated to limited partners	$ 11,886	$ 7,224	$ 9,070
Liberty Property Limited Partnership | Common units
Basic:
Income per common share - basic (USD per share/unit)	$ 3.26	$ 1.92
Diluted:
Income per common share - diluted (USD per share/unit)	$ 3.24	$ 1.91

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Discontinued operations, net gain on property dispositions	$ 303.2	$ 14.6	$ 0
Liberty Property Limited Partnership
Discontinued operations, net gain on property dispositions	$ 303.2	$ 14.6	$ 0

Consolidated Statement of Equit

Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Liberty Property Limited Partnership	Liberty Property Limited PartnershipNon-Controlling Interest	Liberty Property Limited PartnershipGeneral Partner	Liberty Property Limited PartnershipLimited Partner	Common shares	Common unitsLiberty Property Limited Partnership	Common unitsLiberty Property Limited PartnershipGeneral Partner	Common unitsLiberty Property Limited PartnershipLimited Partner	COMMON SHARES OF BENEFICIAL INTEREST	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE LOSS	DISTRIBUTIONS IN EXCESS OF NET INCOME	TOTAL LIBERTY PROPERTY TRUST SHAREHOLDERS’ EQUITY	NONCONTROLLING INTEREST - OPERATING PARTNERSHIP	Non-Controlling Interest
Beginning Balance at Dec. 31, 2015	$ 3,030,254	$ 3,030,254	$ 3,919	$ 2,972,581	$ 53,754					$ 148	$ 3,669,627	$ (22,506)	$ (674,688)	$ 2,972,581	$ 53,754	$ 3,919
Common shares outstanding - Beginning Balance (shares) at Dec. 31, 2015						147,577,984
General Partner's units outstanding - Beginning Balance (shares) at Dec. 31, 2015								147,577,984
Limited Partners' units outstanding - Beginning Balance (shares) at Dec. 31, 2015									3,539,075
Increase (Decrease) in Stockholders' Equity
Net proceeds from the issuance of common shares	13,029										13,029			13,029
Net proceeds from the issuance of common shares (shares)						802,834
Net income	365,673	365,673	258	356,817	8,598								356,817	356,817	8,598	258
Distributions	(285,802)												(278,764)	(278,764)	(6,780)	(258)
Share-based compensation, net of tax withholdings	15,699										15,699			15,699
Contributions from partners		28,728		28,728
Contributions from partners (shares)								802,834
Distributions to partners		(285,802)	(258)	(278,764)	(6,780)
Other comprehensive (loss) income - foreign currency translation	(34,744)	(34,744)		(33,925)	(819)							(33,925)		(33,925)	(819)
Other comprehensive (loss) income - derivative instruments	410	410		400	10							400		400	10
Acquisition of noncontrolling interests	(700)	(700)	982	(1,682)							(1,682)			(1,682)		982
Redemption of noncontrolling interests – common units											132			132	(132)
Redemption of noncontrolling interests – common units (shares)						9,044		9,044
Redemption of limited partners common units for common shares				132	(132)
Redemption of limited partners common units for common shares (shares)									(9,044)
Share repurchase	(40,896)	(40,896)		(40,896)		$ (40,900)	$ (40,900)			(1)	(40,895)			(40,896)
Share repurchase (in shares)						(1,396,844)	(1,400,000)	(1,396,844)
Common shares outstanding - Ending Balance (shares) at Dec. 31, 2016						146,993,018
Limited Partners' units outstanding - Ending Balance (shares) at Dec. 31, 2016									3,530,031
General Partner's units outstanding - Ending Balance (shares) at Dec. 31, 2016								146,993,018
Ending Balance at Dec. 31, 2016	3,062,923	3,062,923	4,901	3,003,391	54,631					147	3,655,910	(56,031)	(596,635)	3,003,391	54,631	4,901
Noncontrolling interest - operating partnership (mezzanine) - Beginning of Period at Dec. 31, 2015	7,537	7,537
Increase (Decrease) in Limited Partners' Equity
Temporary equity, distributions	(472)	(472)
Temporary equity, net Income	472	472
Noncontrolling interest - operating partnership (mezzanine) - End of Period at Dec. 31, 2016	7,537	7,537
Increase (Decrease) in Stockholders' Equity
Net proceeds from the issuance of common shares	8,808										8,808			8,808
Net proceeds from the issuance of common shares (shares)						447,847
Net income	289,573	289,573	481	282,340	6,752								282,340	282,340	6,752	481
Distributions	(241,717)												(235,675)	(235,675)	(5,509)	(533)
Share-based compensation, net of tax withholdings	10,108										10,108			10,108
Contributions from partners		18,916		18,916
Contributions from partners (shares)								447,847
Distributions to partners		(241,717)	(533)	(235,675)	(5,509)
Other comprehensive (loss) income - foreign currency translation	18,066	18,066		17,643	423							17,643		17,643	423
Other comprehensive (loss) income - derivative instruments	$ 605	$ 605		591	14							591		591	14
Redemption of noncontrolling interests – common units											152			152	(152)
Redemption of noncontrolling interests – common units (shares)						9,826		9,826
Redemption of limited partners common units for common shares				152	(152)
Redemption of limited partners common units for common shares (shares)									(9,826)
Share repurchase (in shares)							0
Common shares outstanding - Ending Balance (shares) at Dec. 31, 2017	147,450,691					147,450,691
Limited Partners' units outstanding - Ending Balance (shares) at Dec. 31, 2017	3,520,205	3,520,205							3,520,205
General Partner's units outstanding - Ending Balance (shares) at Dec. 31, 2017		147,450,691						147,450,691
Ending Balance at Dec. 31, 2017	$ 3,148,366	$ 3,148,366	4,849	3,087,358	56,159					147	3,674,978	(37,797)	(549,970)	3,087,358	56,159	4,849
Increase (Decrease) in Limited Partners' Equity
Temporary equity, distributions	(472)	(472)
Temporary equity, net Income	472	472
Noncontrolling interest - operating partnership (mezzanine) - End of Period at Dec. 31, 2017	7,537	7,537
Increase (Decrease) in Stockholders' Equity
Net proceeds from the issuance of common shares	7,333									1	7,332			7,333
Net proceeds from the issuance of common shares (shares)						448,663
Net income	492,131	492,131	1,110	479,607	11,414								479,607	479,607	11,414	1,110
Distributions	(242,665)												(236,459)	(236,459)	(5,687)	(519)
Share-based compensation, net of tax withholdings	9,468										9,468			9,468
Contributions from partners		16,801		16,801
Contributions from partners (shares)								448,663
Distributions to partners		(242,665)	(519)	(236,459)	(5,687)
Other comprehensive (loss) income - foreign currency translation	(14,161)	(14,161)		(13,832)	(329)							(13,832)		(13,832)	(329)
Other comprehensive (loss) income - derivative instruments	$ (3,700)	$ (3,700)		(3,614)	(86)							(3,614)		(3,614)	(86)
Redemption of noncontrolling interests – common units (shares)						0
Redemption of limited partners common units for common shares (shares)									0
Share repurchase (in shares)						0
Common shares outstanding - Ending Balance (shares) at Dec. 31, 2018	147,899,354					147,899,354
Limited Partners' units outstanding - Ending Balance (shares) at Dec. 31, 2018	3,520,205	3,520,205							3,520,205
General Partner's units outstanding - Ending Balance (shares) at Dec. 31, 2018		147,899,354						147,899,354
Ending Balance at Dec. 31, 2018	$ 3,396,772	$ 3,396,772	$ 5,440	$ 3,329,861	$ 61,471					$ 148	$ 3,691,778	$ (55,243)	$ (306,822)	$ 3,329,861	$ 61,471	$ 5,440
Increase (Decrease) in Limited Partners' Equity
Temporary equity, distributions	(472)	(472)
Temporary equity, net Income	472	472
Noncontrolling interest - operating partnership (mezzanine) - End of Period at Dec. 31, 2018	$ 7,537	$ 7,537

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
OPERATING ACTIVITIES
Net income	$ 492,603	$ 290,045	$ 366,145
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including discontinued operations	175,815	183,887	207,673
Amortization of deferred financing costs	3,839	3,750	3,974
Expensed pursuit costs	1,795	5,066	1,016
Impairment - real estate assets, including discontinued operations	39,688	10,632	3,879
Loss on debt extinguishment	0	49	27,099
Equity in earnings of unconsolidated joint ventures	(21,382)	(17,155)	(21,970)
Distributions from unconsolidated joint ventures	747	0	0
Gain on property dispositions	(384,673)	(114,965)	(219,270)
Share-based compensation	13,256	14,119	19,850
Development service fee accrual	58,022	6,220	0
Other	(7,524)	824	(6,128)
Changes in operating assets and liabilities:
Accounts receivable	(2,682)	3,512	421
Deferred rent receivable	(18,922)	(19,605)	(16,927)
Prepaid expenses and other assets	23,259	(33,663)	(32,442)
Accounts payable	(7,183)	10,151	8,943
Accrued interest	513	(82)	(4,276)
Other liabilities	16,295	(6,154)	3,075
Net cash provided by operating activities	383,466	336,631	341,062
INVESTING ACTIVITIES
Investment in properties – acquisitions	(497,616)	(255,639)	(9,216)
Investment in properties – other	(44,976)	(56,104)	(55,406)
Investments in and advances to unconsolidated joint ventures	(81,726)	(46,567)	(70,581)
Distributions from unconsolidated joint ventures	39,235	21,042	63,048
Net proceeds from disposition of properties/land	849,528	379,139	1,192,918
Investment in development in progress	(248,587)	(260,447)	(342,489)
Investment in land held for development	(204,522)	(105,564)	(107,400)
Payment of deferred leasing costs	(29,271)	(37,678)	(32,682)
Increase in escrows and other	(37,158)	(103,834)	(23,265)
Net cash (used in) provided by investing activities	(255,093)	(465,652)	614,927
FINANCING ACTIVITIES
Net proceeds from issuance of common shares	7,333	8,808	13,029
Share repurchases, including shares related to tax withholdings	(4,760)	(5,107)	(46,268)
Proceeds from unsecured notes	0	0	396,648
Repayments of unsecured notes including prepayment premium	0	0	(723,368)
Proceeds from mortgage loans	165,229	0	0
Repayments of mortgage loans	(33,561)	(7,795)	(29,538)
Proceeds from credit facility	1,335,214	835,036	591,300
Repayments on credit facility	(1,280,410)	(476,097)	(850,300)
Payment of deferred financing costs	(1,636)	(5,190)	(3,550)
Distributions paid on common shares	(236,336)	(246,589)	(279,248)
Distributions paid on units/noncontrolling interests	(6,621)	(6,835)	(8,212)
Net cash (used in) provided by financing activities	(55,548)	96,231	(939,507)
Net increase (decrease) in cash, cash equivalents and restricted cash	72,825	(32,790)	16,482
(Decrease) increase in cash, cash equivalents and restricted cash related to foreign currency translation	(2,688)	2,450	(4,828)
Cash, cash equivalents and restricted cash at beginning of year	25,685	56,025	44,371
Cash, cash equivalents and restricted cash at end of year	95,822	25,685	56,025
Liberty Property Limited Partnership
OPERATING ACTIVITIES
Net income	492,603	290,045	366,145
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including discontinued operations	175,815	183,887	207,673
Amortization of deferred financing costs	3,839	3,750	3,974
Expensed pursuit costs	1,795	5,066	1,016
Impairment - real estate assets, including discontinued operations	39,688	10,632	3,879
Loss on debt extinguishment	0	49	27,099
Equity in earnings of unconsolidated joint ventures	(21,382)	(17,155)	(21,970)
Distributions from unconsolidated joint ventures	747	0	0
Gain on property dispositions	(384,673)	(114,965)	(219,270)
Share-based compensation	13,256	14,119	19,850
Development service fee accrual	58,022	6,220	0
Other	(7,524)	824	(6,128)
Changes in operating assets and liabilities:
Accounts receivable	(2,682)	3,512	421
Deferred rent receivable	(18,922)	(19,605)	(16,927)
Prepaid expenses and other assets	23,259	(33,663)	(32,442)
Accounts payable	(7,183)	10,151	8,943
Accrued interest	513	(82)	(4,276)
Other liabilities	16,295	(6,154)	3,075
Net cash provided by operating activities	383,466	336,631	341,062
INVESTING ACTIVITIES
Investment in properties – acquisitions	(497,616)	(255,639)	(9,216)
Investment in properties – other	(44,976)	(56,104)	(55,406)
Investments in and advances to unconsolidated joint ventures	(81,726)	(46,567)	(70,581)
Distributions from unconsolidated joint ventures	39,235	21,042	63,048
Net proceeds from disposition of properties/land	849,528	379,139	1,192,918
Investment in development in progress	(248,587)	(260,447)	(342,489)
Investment in land held for development	(204,522)	(105,564)	(107,400)
Payment of deferred leasing costs	(29,271)	(37,678)	(32,682)
Increase in escrows and other	(37,158)	(103,834)	(23,265)
Net cash (used in) provided by investing activities	(255,093)	(465,652)	614,927
FINANCING ACTIVITIES
Proceeds from unsecured notes	0	0	396,648
Repayments of unsecured notes including prepayment premium	0	0	(723,368)
Proceeds from mortgage loans	165,229	0	0
Repayments of mortgage loans	(33,561)	(7,795)	(29,538)
Proceeds from credit facility	1,335,214	835,036	591,300
Repayments on credit facility	(1,280,410)	(476,097)	(850,300)
Payment of deferred financing costs	(1,636)	(5,190)	(3,550)
Capital contributions	7,333	8,808	13,029
Distributions to partners/noncontrolling interests	(247,717)	(258,531)	(333,728)
Net cash (used in) provided by financing activities	(55,548)	96,231	(939,507)
Net increase (decrease) in cash, cash equivalents and restricted cash	72,825	(32,790)	16,482
(Decrease) increase in cash, cash equivalents and restricted cash related to foreign currency translation	(2,688)	2,450	(4,828)
Cash, cash equivalents and restricted cash at beginning of year	25,685	56,025	44,371
Cash, cash equivalents and restricted cash at end of year	$ 95,822	$ 25,685	$ 56,025

Organization

Organization	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	ORGANIZATION Liberty Property Trust (the “Trust”) is a self-administered and self-managed Maryland real estate investment trust (a “REIT”). Substantially all of the Trust’s assets are owned directly or indirectly, and substantially all of the Trust’s operations are conducted directly or indirectly, by its subsidiary, Liberty Property Limited Partnership, a Pennsylvania limited partnership (the “Operating Partnership” and, together with the Trust and their consolidated subsidiaries, the “Company”). The Trust is the sole general partner and also a limited partner of the Operating Partnership, owning 97.7% of the common equity of the Operating Partnership at December 31, 2018 . The Company owns and operates industrial properties in the United States nationally, as well as in the United Kingdom. The Company intends to divest its remaining office properties (other than its headquarters) over the next few years and focus its efforts and capital solely on its industrial platform. Unless otherwise indicated, the notes to the Consolidated Financial Statements apply to both the Trust and the Operating Partnership. The terms the "Company,” “we,” “our” and “us” means the Trust and Operating Partnership collectively. The Operating Partnership is a variable interest entity ("VIE") of the Trust as the limited partners do not have substantive kick-out or participating rights. The Trust is the primary beneficiary of the Operating Partnership as it has the power to direct the activities of the Operating Partnership and the rights to absorb 97.7% of the net income of the Operating Partnership. The Trust has no significant assets or liabilities other than its investment in the Operating Partnership. As the Operating Partnership is already consolidated in the balance sheets of the Trust, the identification of this entity as a VIE has no impact on the consolidated financial statements of the Trust. In addition, the Company holds a 20% interest in Liberty/Comcast 1701 JFK Boulevard, LP which was determined to be a VIE. The Company determined that it is not the primary beneficiary as the Company and its third-party partner share control of the joint venture. The Company's maximum exposure to loss is equal to its equity investment in the joint venture which was $75.1 million and $17.3 million as of December 31, 2018 and 2017, respectively. All square footage amounts are unaudited.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("US GAAP") requires management to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Principles of Consolidation The consolidated financial statements of the Company include the Trust, the Operating Partnership, wholly owned subsidiaries and those subsidiaries in which the Company owns a majority voting interest with the ability to control operations of the subsidiaries and where no approval, veto or other important rights have been granted to the noncontrolling shareholders. The Company consolidates joint ventures that are considered to be variable interest entities (“VIEs”) where we are the primary beneficiary. The Company (i) evaluates the sufficiency of the total equity investment at risk, (ii) reviews the voting rights and decision-making authority of the equity investment holders as a group and whether there are any guaranteed returns, protection against losses, or capping of residual returns within the group and (iii) establishes whether activities within the venture are on behalf of an investor with disproportionately few voting rights in making this VIE determination. To the extent that the Company (i) is the sole entity that has the power to direct the activities of the VIE and (ii) has the obligation or rights to absorb the VIE's losses or receive its benefits, then the Company would be the primary beneficiary and would consolidate the VIE. All significant intercompany transactions and accounts have been eliminated. Reclassifications Certain amounts from prior years have been reclassified to conform to current-year presentation including reclassifying the accompanying consolidated balance sheets for assets held for sale and the consolidated statements of comprehensive income for discontinued operations. In 2018, the Company began to separately classify other operating expenses in the Consolidated Statements of Comprehensive Income. Other operating expenses include expensed pursuit costs, system implementation costs and severance costs. The Company is incurring costs associated with its efforts to implement new financial and operating systems in certain cloud computing arrangements. The Company evaluated the arrangements in accordance with ASU 2015-05 "Customer's Accounting for Fees Paid in a Cloud Computing Arrangement" and concluded that such arrangements are service contracts under the standard. Accordingly, the Company expenses substantially all costs as incurred. Certain costs that relate to the software service agreements received over time are set up as prepaid and expensed over the applicable service period. These costs include license costs during the implementation period as well as consulting, personnel and other direct costs related to the implementation. The Company capitalizes pre-development costs incurred in pursuit of new development opportunities for which the Company currently believes future development is probable. Future development is dependent upon various factors, including zoning and regulatory approval, rental market conditions and construction costs. Initial pre-development costs incurred for pursuits for which future development is not yet considered probable are expensed as incurred. In addition, if the status of a future development by the Company is no longer probable, any capitalized pre-development costs are written off with a charge to expense. Severance costs are incurred in conjunction with certain headcount reductions relating primarily to the Company's change in strategy. Previously, expensed pursuit costs were on a separate line item on the Company's Consolidated Statements of Comprehensive Income in amounts per the table below. Systems implementation costs and severance costs were included in general and administrative expense in amounts as follows (in thousands): 2017 2016 Expensed pursuit costs $ 5,066 $ 1,016 General and administrative expense 1,011 4,001 Concentration of Credit Risk As of December 31, 2018, wholly owned properties were leased to 1,084 customers. The geographic locations that comprise greater than 10% of our segment level operating revenues were Lehigh Valley/Central PA and Carolinas/Richmond. Our customers engage in a wide variety of businesses. No single customer generated more than 4.3% of our consolidated operating rental revenues during 2018. In 2018, the Sears Holdings Corporation filed for reorganization under Chapter 11 of the federal bankruptcy laws. This tenant represents 0.8% of consolidated operating rental revenues during 2018. Real Estate and Depreciation The properties are recorded at cost and are depreciated using the straight line method over their estimated useful lives. The estimated useful lives are as follows: Building and improvements 40 years (blended) Capital improvements 15 - 20 years Equipment 5 - 10 years Tenant improvements Term of the related lease The Company capitalizes costs associated with development and redevelopment activities, capital improvements, tenant improvements and leasing activities, including compensation costs. Expenditures directly related to the improvement of real estate, including interest and other costs capitalized on development and redevelopment projects and land being readied for development, are included in net real estate and are stated at cost. The Company considers a development property substantially complete upon the completion of tenant build-out, but no later than one year after the completion of major construction activity. These capitalized costs include pre-construction costs essential to the development of the property, construction costs, interest costs, real estate taxes, development related compensation and other costs incurred during the period of development. The determination to capitalize rather than expense costs requires the Company to evaluate the status of the development activity. The total of capitalized compensation costs directly related to development, redevelopment, capital improvements, and tenant improvements for the years ended December 31, 2018 , 2017 and 2016 was $7.1 million , $5.5 million and $7.2 million , respectively. Construction related payables at December 31, 2018 and 2017 were $48.1 million and $49.3 million , respectively. The Company allocates the purchase price of real estate acquired to land, building and improvements and intangibles based on the relative fair value of each component. Lease values for acquired properties are determined based on the present value (using a discount rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to each in-place lease and (ii) management's estimate of fair market lease rates for each corresponding in-place lease ("Market Value Intangible"). Origination values are also assigned to in-place leases, and, where appropriate, value is assigned to customer relationships ("Origination Value Intangible"). Acquisition-related costs for asset acquisitions are capitalized and included in net real estate at cost. Expenditures for maintenance and repairs are charged to operations as incurred. The Company depreciates the amounts allocated to building and improvements over 40 years and amortizes the amounts allocated to intangibles relating to in-place leases, which are included in deferred financing and leasing costs and other liabilities in the accompanying consolidated balance sheets, over the remaining term of the related leases. Market Value Intangible amortization is recorded as rental revenue. Origination Value Intangible amortization is recorded as depreciation and amortization. This calculation includes both the remaining noncancelable period and any bargain renewal option periods. Once a property is designated as held for sale, no further depreciation expense is recorded. The Company evaluates its real estate investments upon occurrence of a significant adverse change in its operations and/or market price, an expectation that the asset will be sold or otherwise disposed of before the end of its estimated useful life, among other factors, to assess whether any impairment indicators are present that affect the recovery of the recorded value. If indicators of impairment are identified, the Company estimates the future undiscounted cash flows from the use and eventual disposition of the property and compares this amount to the carrying value of the property. If any real estate investment is considered impaired, a loss is recognized to reduce the carrying value of the property to its estimated fair value. If held for sale, a property is not considered impaired unless its estimated fair value (less costs to sell) is less than the property's book value at the balance sheet date. Investments in Unconsolidated Joint Ventures The Company accounts for its investments in unconsolidated joint ventures using the equity method of accounting as the Company exercises significant influence, but does not control these entities. Under the equity method of accounting, the net equity investment of the Company is reflected in the accompanying consolidated balance sheets and the Company's share of net income from the joint ventures is included in the accompanying consolidated statements of comprehensive income. On a periodic basis, management assesses whether there are any indicators that the value of the Company's investments in unconsolidated joint ventures may be other-than-temporarily-impaired. An investment is impaired only if management's estimate of the value of the investment is less than the carrying value of the investment, and such decline in value is deemed to be other-than-temporary. To the extent impairment has occurred, the loss is measured as the excess of the carrying amount of the investment over the estimated fair value of the investment. The estimated fair value of the investments is determined using a discounted cash flow model which is a Level 3 valuation under ASC 820, " Fair Value Measurement ." The Company considers a number of assumptions that are subject to economic and market uncertainties including, among others, demand for space, competition for tenants, changes in market rental rates, operating costs, capitalization rates, holding periods and discount rates. No other-than-temporary impairment losses on the Company's investments in unconsolidated joint ventures were recognized during the years ended December 31, 2016, 2017 or 2018. Cash and Cash Equivalents Highly liquid investments with a maturity of three months or less when purchased are classified as cash equivalents. Restricted Cash Restricted cash includes tenant security deposits and escrow funds that the Company maintains pursuant to certain mortgage loans. Restricted cash also includes the undistributed proceeds from the sale of residential land in Kent County, United Kingdom. Accounts Receivable/Deferred Rent Receivable The Company's accounts receivable are comprised of rents and charges for property operating costs due from tenants. The Company's deferred rent receivable represents the cumulative difference between rent revenue recognized on a straight line basis and contractual payments due under the terms of tenant leases. The Company periodically performs a detailed review of amounts due from tenants to determine if accounts receivable and deferred rent receivable balances are collectible. Based on this review, accounts receivable and deferred rent receivable are reduced by an allowance for doubtful accounts. The Company considers tenant credit quality and payment history and general economic conditions in determining the allowance for doubtful accounts. If the accounts receivable balance or the deferred rent receivable balance is subsequently deemed uncollectible, the receivable and allowance for doubtful account balance are written off. The allowance for doubtful accounts at December 31, 2018 and 2017 was $6.4 million and $6.6 million , respectively. The Company recognized bad debt expense of $1.4 million , $0.6 million and $0.6 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Revenue Recognition The Company earns rental income under operating leases with tenants. Rental income is recognized on a straight line basis over the applicable non-cancelable lease term. Operating expense reimbursements consisting of amounts due from tenants for real estate taxes, utilities and other recoverable costs are recognized as revenue in the period in which the corresponding expenses are incurred. The Company considers any renewal options in determining the lease term. To the extent a lease includes a tenant option to renew or extend the duration of the lease at a fixed or determinable rental rate, the Company evaluates whether or not that option represents a bargain renewal option by analyzing if there is reasonable assurance at lease inception that the tenant will exercise the option because the rental rate is sufficiently lower than the expected rental rate for equivalent property under similar terms and conditions at the exercise date. Termination fees (included in rental revenue) are fees that the Company has agreed to accept in consideration for permitting certain tenants to terminate their lease prior to the contractual expiration date. The Company recognizes termination fees during the period that landlord services are rendered in accordance with Securities and Exchange Commission Staff Accounting Bulletin 104, " Revenue Recognition ," after the following conditions are met: a. the termination agreement is executed, b. the termination fee is determinable, and c. collectability of the termination fee is assured. Effective January 1, 2018, the Company adopted the "New Revenue Standards," comprised of: ASU 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASU 2014-09”), which supersedes nearly all existing revenue recognition guidance (except revenue in the scope of other accounting standards, including standards related to leasing) as well as the following standards subsequently issued by the FASB related to ASU 2014-09: ASU 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations ; ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing ; ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients ; ASU 2017-05, Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20) , and ASU 2017-13, Revenue from Contracts with Customers (Topic 606): Amendments to SEC Paragraphs Pursuant to the Staff Announcement at the July 20, 2017 EITF Meeting and Rescission of Prior SEC Staff Announcements and Observer Comments. The New Revenue Standards provide a unified model to determine how revenue is recognized. In accordance with the New Revenue Standards, the Company performs the following steps: (i) identify the contract with the customer, (ii) identify the performance obligations within the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations and (v) recognize revenue when (or as) a performance obligation is satisfied. The Company evaluated each of its revenue streams: lease agreement revenue, development service fee revenue, deferred land sale revenue and gain or loss on sale of nonfinancial assets and adopted the New Revenue Standards effective January 1, 2018 using the modified retrospective approach. The Company concluded that there are no revenue streams from its lease agreements that are covered by the New Revenue Standards. The Company adopted the practical expedient to assess the recognition of revenue for open contracts during the transition period. There was no adjustment to the opening balance of retained earnings recorded at January 1, 2018. In the fourth quarter of 2016, the Company entered into an agreement relating to the fee development of an office building at its Camden Waterfront project in Camden, NJ. Project revenues and related costs and expenses are presented on a gross basis as "Development service fee income" and "Development service fee expense" in the Consolidated Statements of Comprehensive Income. Additionally, at the same time, the Company began classifying development fees and expenses relating to its fee development arrangements for certain unconsolidated joint venture projects in a manner consistent with the Camden project described above. Previously, development service fee income relating to its unconsolidated joint ventures had been classified as other income and development service fee expense had been classified as general and administrative expense in amounts as follows: Nine months ended September 30, 2016 (unaudited) Other income $ 3,789 General and administrative expense $ 3,210 For the years ended December 31, 2017 and 2016, revenue and expense associated with service fee development was accounted for under the percentage of completion method. Revenues were recognized on the percentage of completion method based on applicable costs incurred with respect to each development agreement. The Company used the relative sales value method to allocate costs and recognize profits from service fee development. Under the relative sales value method, estimates of aggregate project revenues and aggregate project costs are used to determine the allocation of project cost of sales and the resulting profit in each accounting period. In subsequent periods, cost of sale allocations and the resulting profits are adjusted to reflect changes in the actual and estimated costs and revenues of each project. Provisions for estimated losses on uncompleted contracts are recognized immediately in the period in which such losses are determined. The New Revenue Standards did not have an impact on the amount and timing of recognizing the Company's development service fee income. The Company recognizes development service fee income on a variable basis as a percentage of costs incurred on third party development contracts. Property development services, which are a single performance obligation, continue to be satisfied and recognized over time. The Company measures its progress toward completing the performance obligation under each arrangement. The measurement of the transfer of value to the customer for these services utilizes the input method (actual costs incurred against anticipated project costs) since this method best depicts the actual transfer of value promised to the customer. Estimated expected losses on such contracts are accrued in the period in which they are determinable. The total amount of consideration to be received from these projects is assessed on a quarterly basis. The Company receives cash as it sells improved land sites on behalf of its development partner to home builders in the United Kingdom. These agreements contain a pre-emption clause and a seller's call option. The Company recognizes revenue as the pre-emption period or seller's call option lapses utilizing the output method. There was $2.4 million , $0.3 million , and $2.6 million in revenue recognized for such contracts during the years ended December 31, 2018, 2017 and 2016, respectively. The New Revenue Standards did not have an impact on the gain or loss on sale of nonfinancial assets. The New Revenue Standards require the Company to derecognize nonfinancial assets once it transfers control of a distinct nonfinancial asset or distinct in substance nonfinancial asset. Additionally, when the Company transfers its controlling interest in a nonfinancial asset, but retains a noncontrolling ownership interest, the Company is required to measure any noncontrolling interest it receives or retains at fair value. The guidance requires companies to recognize a full gain or loss on the transaction. See Note 6 - Real Estate, Note 7 - Investments in Unconsolidated Joint Ventures and Note 19 - Accounting for the Impairment or Disposal of Long-lived Assets for further discussion of sales of nonfinancial assets. Estimated gross revenue related to the remaining performance obligations under existing contracts (before allocation of related costs and expenses) as of December 31, 2018 that will be recognized as revenue in future periods was approximately $37.1 million , which is expected to be recognized through 2021. Deferred Financing and Leasing Costs Costs incurred in connection with leasing or financing of the credit facilities are capitalized and amortized on a straight line basis over the term of the related lease or loan. Costs incurred in connection with the financing of mortgage loans or unsecured notes are reported as a deduction from the face amount of that liability and amortized on a straight line basis over the term of the related loan. Deferred financing cost amortization is reported as interest expense. Certain employees of the Company are compensated for leasing services related to the Company's properties. The compensation directly related to these leasing services is capitalized and amortized as a deferred leasing cost over the term of the related lease. The total of this capitalized compensation was $2.7 million , $3.6 million and $3.8 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Effective January 1, 2019, as a result of the New Lease Standard, only incremental, direct costs will be capitalizable and therefore, certain compensation costs for leasing services will be expensed as incurred. Fair Value of Financial Instruments ASC 820, Fair Value Measurements and Disclosures , gives guidance on the fair value measurement of a financial asset or liability. Inputs used to develop fair value are classified in one of three categories: Level 1 inputs (quoted prices (unadjusted) in active markets for identical assets or liabilities), Level 2 inputs (inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly) and Level 3 inputs (unobservable inputs for the asset or liability). The following disclosure of estimated fair value was determined by management using available market information and appropriate valuation methodologies. However, considerable judgment is necessary to interpret market data and develop estimated fair value. Accordingly, the following estimates are not necessarily indicative of the amounts the Company could have realized on disposition of the financial instruments at December 31, 2018 and December 31, 2017 . The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. The carrying value of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accrued interest, dividend and distributions payable and other liabilities are reasonable estimates of fair value because of the short-term nature of these instruments. The carrying value of the outstanding amounts under the Company's credit facilities is also a reasonable estimate of fair value because interest rates float at a rate based on LIBOR. The Company determines the fair value of its interest rate swaps by using the standard methodology of netting discounted future fixed cash payments with the discounted expected variable cash receipts. These variable cash receipts of interest rate swaps are based on expectations of future LIBOR interest rates (forward curves) estimated by observing market LIBOR interest rate curves. This is a Level 2 fair value calculation. Also, credit valuation adjustments are factored into the fair value calculations to account for potential nonperformance risk. These credit valuation adjustments were concluded to be not significant inputs for the fair value calculations for the periods presented. See Note 20 - Derivative Instruments. The Company used a discounted cash flow model to determine the estimated fair value of its debt as of December 31, 2018 and December 31, 2017 . This is a Level 3 fair value calculation. The inputs used in preparing the discounted cash flow model include actual maturity dates and scheduled cash flows as well as estimates for market value discount rates. The Company updates the discounted cash flow model on a quarterly basis to reflect any changes in the Company's debt holdings and changes to discount rate assumptions. The following summarizes the fair value of the Company's mortgage loans and unsecured notes at December 31, 2018 and December 31, 2017 (in thousands): Mortgage Loans Unsecured Notes Carrying Value Fair Value Carrying Value Fair Value As of December 31, 2018 $ 395,202 $ 397,167 $ 2,285,698 $ 2,295,699 As of December 31, 2017 $ 267,093 $ 267,298 $ 2,283,513 $ 2,359,998 Income Taxes The Company has elected to be taxed as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the "Code"). As a result, the Company generally is not subject to federal income taxation at the corporate level to the extent it distributes annually at least 100% of its REIT taxable income, as defined in the Code, to its shareholders and satisfies certain other organizational and operational requirements. The Company has met these requirements and, accordingly, no provision has been made for federal income taxes in the accompanying consolidated financial statements. If the Company fails to qualify as a REIT in any taxable year, the Company will be subject to federal income tax on its taxable income at regular corporate rates (including any alternative minimum tax for those tax years beginning prior to January 1, 2018) and may not be able to qualify as a REIT for the four subsequent taxable years. Even as a REIT, the Company may still be subject to certain state and local income and property taxes, and to federal income and excise taxes on undistributed taxable income. The Company continues to consider and implement the relevant provisions of the Tax Cuts and Jobs Act (the "TCJA"), which was signed into law on December 22, 2017 and which generally took effect for taxable years beginning on or after January 1, 2018. Based upon its assessment, when combined with the guidance issued to date by both the Internal Revenue Service and the United States Treasury Department, the Company does not reasonably believe or expect those provisions, or the TCJA in general, will have a material impact on its overall financial condition, business operations or ability to continue to qualify as a REIT on a going forward basis. Several of the Company's subsidiaries are taxable REIT subsidiaries (each a "TRS") and are subject to federal and state income taxes separate from the Company. In general, a TRS may perform additional services for tenants and generally may engage in real estate or non-real estate businesses that are not permitted REIT activities. The Company itself is also subject to tax in certain states and the United Kingdom. Accordingly, the Company recognizes federal, state and foreign income taxes in accordance with US GAAP, as applicable. In addition, the TCJA implemented a one-time deemed repatriation tax on offshore corporate profits, including any such profits which the Company may have accumulated over the years in its offshore TRSs, at the reduced rates of 15.5% on cash assets and 8% on noncash assets. The Company has reviewed its accumulated offshore earnings through December 31, 2017 and this provision of the TCJA did not have a material impact on the Company’s overall financial condition or results of operation or its 2017 federal and state tax return filings. Currently there are no uncertain tax positions or possibly significant unrecognized tax benefits that are reasonably expected to occur within the next 12 months. The Company's policy is to recognize interest accrued related to unrecognized benefits in interest expense and penalties in other expense. There were no interest or penalties deducted in any of the years ended December 31, 2018 , 2017 and 2016 and no interest and penalties accrued at December 31, 2018 or December 31, 2017 which related to any uncertain tax positions or significant unrecognized tax benefits. As of December 31, 2018, certain of the Company's TRSs have estimated net operating loss ("NOL") carryforwards available of approximately $20.8 million . Unless reduced or utilized, these NOL carryforwards are set to begin expiring in 2020 . Additionally, the TCJA reduced the corporate federal tax rate in the U.S. from 35% to 21% effective for tax years beginning after December 31, 2017 while also reducing the amount of newly generated NOLs that can generally be utilized by a taxpayer in any tax year from 100% of net taxable income to 90%. As such, deferred tax assets and liabilities, where applicable, were remeasured to account for these changes. After taking into consideration the projected future net taxable income at these entities, and consistent with prior periods, the Company has determined that a valuation allowance for the full carrying value of NOL carryforwards is appropriate. The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction, certain state and local jurisdictions, the United Kingdom and (in prior years) Luxembourg. With few exceptions, the Company and its subsidiaries are no longer subject to examination by taxing authorities in these jurisdictions for years prior to 2012. The Federal tax cost basis of the wholly owned real estate was $7.1 billion and $6.8 billion at December 31, 2018 and 2017 , respectively. Share-Based Compensation Share-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as expense over the employees' requisite service period. The Company recognizes forfeitures on share based compensation as they occur. Derivative Financial Instruments The Company borrows funds at a combination of fixed and variable rates. Borrowings under our Facilities and certain bank mortgage loans bear interest at variable rates. Our long-term debt typically bears interest at fixed rates. Our interest rate risk management objectives are to limit generally the impact of interest rate changes on earnings and cash flows and to lower our overall borrowing costs. To achieve these objectives, from time to time, we enter into interest rate hedge contracts such as collars, swaps, caps and treasury lock agreements in order to mitigate our interest rate risk with respect to various debt instruments. We generally do not hold or issue these derivative contracts for trading or speculative purposes. The interest rate on all of our variable rate debt is generally adjusted at one or three month intervals, subject to settlements under interest rate hedge contracts. Interest rate swaps involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive loss (for the Trust) and general partner's equity and limited partners' equity - common units (for the Operating Partnership) and is subsequently reclassified into interest expense in the period that the hedged forecasted transaction affects earnings. Foreign Currency The functional currency of the Company's United Kingdom operations is pounds sterling. The Company translates the financial statements for the United Kingdom operations into US dollars. For the Trust, gains and losses resulting from this translation are included in accumulated other comprehensive loss as a separate component of shareholders' equity and a proportionate amount of gain or loss is allocated to noncontrolling interest - operating partnership - common units. For the Operating Partnership, gains and losses resulting from this translation are included in general partner's equity and limited partners' equity - common units. Upon sale or upon complete or substantially complete liquidation of the Company's foreign investment, the gain or loss on the sale will include the cumulative translation adjustments that have been previously recorded in accumulated other comprehensive loss and noncontrolling interest - operating partnership - common units (for the Trust) and in general partner's equity and limited partners' equity - common units (for the Opera

Income per Common Share of the

Income per Common Share of the Trust	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Income per Common Share of the Trust	INCOME PER COMMON SHARE OF THE TRUST The following table sets forth the computation of basic and diluted income per common share of the Trust (in thousands except per share amounts): 2018 2017 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 160,677 147,275 $ 1.09 $ 242,066 146,742 $ 1.65 Dilutive shares for long-term compensation plans — 946 — 799 Income from continuing operations net of noncontrolling interest - diluted $ 160,677 148,221 $ 1.09 $ 242,066 147,541 $ 1.64 Discontinued operations net of noncontrolling interest - basic $ 318,930 147,275 $ 2.17 $ 40,274 146,742 $ 0.27 Dilutive shares for long-term compensation plans — 946 — 799 Discontinued operations net of noncontrolling interest - diluted $ 318,930 148,221 $ 2.15 $ 40,274 147,541 $ 0.27 Net income available to common shareholders - basic $ 479,607 147,275 $ 3.26 $ 282,340 146,742 $ 1.92 Dilutive shares for long-term compensation plans — 946 — 799 Net income available to common shareholders - diluted $ 479,607 148,221 $ 3.24 $ 282,340 147,541 $ 1.91 2016 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 330,320 146,204 $ 2.26 Dilutive shares for long-term compensation plans — 685 Income from continuing operations net of noncontrolling interest - diluted $ 330,320 146,889 $ 2.25 Discontinued operations net of noncontrolling interest - basic $ 26,497 146,204 $ 0.18 Dilutive shares for long-term compensation plans — 685 Discontinued operations net of noncontrolling interest - diluted $ 26,497 146,889 $ 0.18 Net income available to common shareholders - basic $ 356,817 146,204 $ 2.44 Dilutive shares for long-term compensation plans — 685 Net income available to common shareholders - diluted $ 356,817 146,889 $ 2.43 Dilutive shares for long-term compensation plans represent the unvested common shares outstanding during the year as well as the dilutive effect of outstanding options. There were no anti-dilutive options in 2018 or 2017. There were 0.8 million anti-dilutive options that were excluded in 2016 from the computation of diluted income per common share as the exercise price was higher than the average share price of the Company in 2016. During the years ended December 31, 2018 , 2017 and 2016 , 151,000 , 193,000 and 369,000 common shares, respectively, were issued upon the exercise of options. During the year ended December 31, 2018 , there were no common shares issued in exchange for common units. During the years ended December 31, 2017 and 2016 , individuals acquired 9,826 and 9,044 common shares, respectively, in exchange for the same number of common units. These individuals acquired these common units in connection with their contributions to the Operating Partnership of certain assets in prior years. The exchange of common shares for common units is exempt from the registration requirement of the Securities Act of 1933, as amended, pursuant to Section 4(2) thereunder. During the years ended December 31, 2018 , 2017 and 2016 , declared dividends per common share were $1.60 , $ 1.60 and $ 1.90 , respectively.

Income per Common Unit of the O

Income per Common Unit of the Operating Partnership	12 Months Ended
	Dec. 31, 2018
Earnings Per Unit, Basic and Diluted [Line Items]
Income per Common Unit of the Operating Partnership	INCOME PER COMMON SHARE OF THE TRUST The following table sets forth the computation of basic and diluted income per common share of the Trust (in thousands except per share amounts): 2018 2017 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 160,677 147,275 $ 1.09 $ 242,066 146,742 $ 1.65 Dilutive shares for long-term compensation plans — 946 — 799 Income from continuing operations net of noncontrolling interest - diluted $ 160,677 148,221 $ 1.09 $ 242,066 147,541 $ 1.64 Discontinued operations net of noncontrolling interest - basic $ 318,930 147,275 $ 2.17 $ 40,274 146,742 $ 0.27 Dilutive shares for long-term compensation plans — 946 — 799 Discontinued operations net of noncontrolling interest - diluted $ 318,930 148,221 $ 2.15 $ 40,274 147,541 $ 0.27 Net income available to common shareholders - basic $ 479,607 147,275 $ 3.26 $ 282,340 146,742 $ 1.92 Dilutive shares for long-term compensation plans — 946 — 799 Net income available to common shareholders - diluted $ 479,607 148,221 $ 3.24 $ 282,340 147,541 $ 1.91 2016 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 330,320 146,204 $ 2.26 Dilutive shares for long-term compensation plans — 685 Income from continuing operations net of noncontrolling interest - diluted $ 330,320 146,889 $ 2.25 Discontinued operations net of noncontrolling interest - basic $ 26,497 146,204 $ 0.18 Dilutive shares for long-term compensation plans — 685 Discontinued operations net of noncontrolling interest - diluted $ 26,497 146,889 $ 0.18 Net income available to common shareholders - basic $ 356,817 146,204 $ 2.44 Dilutive shares for long-term compensation plans — 685 Net income available to common shareholders - diluted $ 356,817 146,889 $ 2.43 Dilutive shares for long-term compensation plans represent the unvested common shares outstanding during the year as well as the dilutive effect of outstanding options. There were no anti-dilutive options in 2018 or 2017. There were 0.8 million anti-dilutive options that were excluded in 2016 from the computation of diluted income per common share as the exercise price was higher than the average share price of the Company in 2016. During the years ended December 31, 2018 , 2017 and 2016 , 151,000 , 193,000 and 369,000 common shares, respectively, were issued upon the exercise of options. During the year ended December 31, 2018 , there were no common shares issued in exchange for common units. During the years ended December 31, 2017 and 2016 , individuals acquired 9,826 and 9,044 common shares, respectively, in exchange for the same number of common units. These individuals acquired these common units in connection with their contributions to the Operating Partnership of certain assets in prior years. The exchange of common shares for common units is exempt from the registration requirement of the Securities Act of 1933, as amended, pursuant to Section 4(2) thereunder. During the years ended December 31, 2018 , 2017 and 2016 , declared dividends per common share were $1.60 , $ 1.60 and $ 1.90 , respectively.
Liberty Property Limited Partnership
Earnings Per Unit, Basic and Diluted [Line Items]
Income per Common Unit of the Operating Partnership	INCOME PER COMMON UNIT OF THE OPERATING PARTNERSHIP The following table sets forth the computation of basic and diluted income per common unit of the Operating Partnership (in thousands, except per unit amounts): 2018 2017 Income (Numerator) Weighted Average Units (Denominator) Per Unit Income (Numerator) Weighted Average Units (Denominator) Per Unit Income from continuing operations - net of noncontrolling interest - consolidated joint ventures $ 164,955 $ 248,325 Less: Preferred unit distributions (472 ) (472 ) Income from continuing operations available to common unitholders - basic $ 164,483 150,795 $ 1.09 $ 247,853 150,270 $ 1.65 Dilutive units for long-term compensation plans — 946 — 799 Income from continuing operations available to common unitholders - diluted $ 164,483 151,741 $ 1.09 $ 247,853 151,069 $ 1.64 Income from discontinued operations - basic $ 326,538 150,795 $ 2.17 $ 41,239 150,270 $ 0.27 Dilutive units for long-term compensation plans 946 799 Income from discontinued operations - diluted $ 326,538 151,741 $ 2.15 $ 41,239 151,069 $ 0.27 Income available to common unitholders - basic $ 491,021 150,795 $ 3.26 $ 289,092 150,270 $ 1.92 Dilutive units for long-term compensation plans 946 799 Income available to common unitholders - diluted $ 491,021 151,741 $ 3.24 $ 289,092 151,069 $ 1.91 2016 Income (Numerator) Weighted Average Units (Denominator) Per Unit Income from continuing operations net of noncontrolling interest - consolidated joint ventures $ 338,758 Less: Preferred unit distributions (472 ) Income from continuing operations available to common unitholders - basic $ 338,286 149,740 $ 2.26 Dilutive units for long-term compensation plans — 685 Income from continuing operations available to common unitholders - diluted $ 338,286 150,425 $ 2.25 Income from discontinued operations - basic $ 27,129 149,740 $ 0.18 Dilutive units for long-term compensation plans — 685 Income from discontinued operations - diluted $ 27,129 150,425 $ 0.18 Income available to common unitholders - basic $ 365,415 149,740 $ 2.44 Dilutive units for long-term compensation plans — 685 Income available to common unitholders - diluted $ 365,415 150,425 $ 2.43 Dilutive units for long-term compensation plans represent the unvested common units outstanding during the year as well as the dilutive effect of outstanding options. There were no anti-dilutive options in 2018 and 2017. There were 0.8 million anti-dilutive options excluded in 2016 from the computation of diluted income per common unit as the exercise price was higher than the average unit price of the Company in 2016. During the years ended December 31, 2018 , 2017 and 2016 , 151,000 , 193,000 and 369,000 common units, respectively, were issued upon the exercise of options. During the year ended December 31, 2018 , there were no common shares issued in exchange for common units. During the years ended December 31, 2017 and 2016 , individuals acquired 9,826 and 9,044 common shares of the Trust, respectively, in exchange for the same number of common units of the Operating Partnership. These individuals acquired these common units in connection with their contributions to the Operating Partnership of certain assets in prior years. The exchange of common shares for common units is exempt from the registration requirement of the Securities Act of 1933, as amended, pursuant to Section 4(2) thereunder. During the years ended December 31, 2018 , 2017 and 2016 , declared dividends per common unit were $1.60 , $1.60 and $1.90 , respectively.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Loss	ACCUMULATED OTHER COMPREHENSIVE LOSS The following table sets forth the components of Accumulated Other Comprehensive Loss (in thousands): December 31, 2018 2017 Foreign Currency Translation: Beginning balance $ (38,701 ) $ (56,767 ) Translation adjustment (14,161 ) 18,066 Ending balance (52,862 ) (38,701 ) Derivative Instruments: Beginning balance 150 (455 ) Unrealized (loss) gain (3,472 ) 152 Reclassification adjustment (1) (228 ) 453 Ending balance (3,550 ) 150 Total accumulated other comprehensive loss (56,412 ) (38,551 ) Less: portion included in noncontrolling interest – operating partnership 1,169 754 Total accumulated other comprehensive loss included in shareholders' equity $ (55,243 ) $ (37,797 ) (1) Amounts reclassified out of Accumulated Other Comprehensive Loss/General & Limited Partner's Equity into contractual interest expense.

Real Estate

Real Estate	12 Months Ended
	Dec. 31, 2018
Real Estate [Abstract]
Real Estate	REAL ESTATE The Company owns and operates industrial and office properties. The carrying value of these operating properties by type as of December 31, 2018 and 2017 is as follows (in thousands): Land Building and Land and Accumulated Improvements Improvements Total Depreciation 2018 Industrial properties $ 1,233,655 $ 4,353,225 $ 5,586,880 $ 926,703 Office properties 23,051 302,559 325,610 48,269 2018 Total $ 1,256,706 $ 4,655,784 $ 5,912,490 $ 974,972 2017 Industrial properties $ 1,000,810 $ 3,867,834 $ 4,868,644 $ 810,044 Office properties 22,743 245,329 268,072 41,580 2017 Total $ 1,023,553 $ 4,113,163 $ 5,136,716 $ 851,624 Depreciation expense was $143.4 million , $148.9 million and $166.8 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Information on the operating properties the Company sold during the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Carolinas/Richmond 1 1.5 80,000 $ 7,094 Chicago/Minneapolis — 8.3 — 2,714 Lehigh/Central PA — 66.2 — 9,700 Philadelphia 1 3.1 207,779 130,818 Southeastern PA 32 — 2,325,039 402,708 United Kingdom — — — 65,334 (1) Other 5 — 805,746 255,000 Total 39 79.1 3,418,564 $ 873,368 (1) The Company sold development rights in Horsham, UK. 2017 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 3 — 136,110 $ 8,917 Florida — 16.4 — 13,256 Houston 1 42.2 206,808 36,145 Lehigh/Central PA 2 44.3 1,683,876 249,045 Southeastern PA 4 3.0 313,410 56,156 Other — 7.2 — 3,739 Total 10 113.1 2,340,204 $ 367,258 2016 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 24 5.3 2,037,275 $ 199,825 Florida 51 12.1 3,509,641 505,828 Lehigh/Central PA 1 — 120,777 11,200 Philadelphia — 1.0 — 2,640 Southeastern PA 31 — 2,165,002 266,821 Other 18 18.0 1,631,295 224,241 Total 125 36.4 9,463,990 $ 1,210,555 During the year ended December 31, 2015, the Company completed a portfolio sale consisting of 41 properties and 20 acres of land in the Southeastern PA segment. As of December 31, 2016, the Company had deferred gain recognition related to this sale in the amount of $14.3 million . During the year ended December 31, 2017, the contingency related to the portfolio sale was settled and the Company recognized the deferred gain in the accompanying consolidated statements of comprehensive income. Information on the operating properties and land parcels the Company acquired during the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Florida — 30.8 — $ 15,478 Lehigh/Central PA — 170.2 — 34,092 Southern California 5 36.0 1,450,041 291,916 United Kingdom 7 8.7 1,116,421 149,582 Other 4 29.2 1,484,612 141,502 Total 16 274.9 4,051,074 $ 632,570 2017 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Carolinas/Richmond — 10.7 — $ 1,242 Lehigh/Central PA — 94.6 — 17,798 Southern California 3 — 1,163,233 176,310 United Kingdom — 34.6 — 12,550 Other 5 113.6 698,646 88,498 Total 8 253.5 1,861,879 $ 296,398 2016 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Carolinas/Richmond — 12.7 — $ 2,251 Chicago/Minneapolis 1 5.6 73,160 11,064 Lehigh/Central PA — 76.0 — 15,395 Philadelphia — 6.2 — 13,943 Southeastern PA — 8.3 — 3,344 Southern California — 8.1 — 4,041 Other — 99.5 — 10,854 Total 1 216.4 73,160 $ 60,892

Investments in Unconsolidated J

Investments in Unconsolidated Joint Ventures	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Joint Ventures	INVESTMENTS IN UNCONSOLIDATED JOINT VENTURES Listed below are the unconsolidated joint ventures in which the Company has a noncontrolling interest. The Company receives fees from these joint ventures for services it provides. These services include property management, leasing, development and administration. These fees are generally included in interest and other income in the accompanying consolidated statements of comprehensive income. For the three months ended December 31, 2016, the Company began including development-related fees in development service income in the consolidated statements of comprehensive income. The Company may also receive a promoted interest if certain return thresholds are met. The accounting policies for the unconsolidated joint ventures in which the Company has a noncontrolling interest are the same as those for the Company. On a periodic basis, management assesses whether there are any indicators that the value of the properties owned by the unconsolidated joint ventures may be impaired. As detailed below, management has determined that certain assets are impaired as the unconsolidated joint ventures dispose of and anticipate the potential disposition of certain properties prior to the end of their remaining useful lives. Liberty Venture I, LP As of December 31, 2018 , the Company had a 25% interest in Liberty Venture I, LP, an entity engaged in the ownership of industrial properties in New Jersey. This joint venture is part of the Company's New Jersey reportable segment. As of December 31, 2018 , the joint venture owned 29 industrial properties totaling 4.8 million square feet. During the year ended December 31, 2018 the joint venture brought into service one industrial building totaling 302,000 square feet which is 100% occupied. The total investment for the joint venture is $21.0 million . The Company had a receivable from Liberty Venture I, LP for $1,000 and $223,000 as of December 31, 2018 and 2017, respectively. This related party receivable is reflected as prepaid expenses and other assets in the Company's consolidated balance sheets. The Company recognized $1.3 million , $1.6 million and $2.3 million in fees for services during the years ended December 31, 2018 , 2017 and 2016 , respectively. Kings Hill Unit Trust As of December 31, 2018 , the Company had a 20% interest in Kings Hill Unit Trust, an entity engaged in the ownership of office properties in the County of Kent, United Kingdom. This joint venture is part of the Company's United Kingdom reportable segment. As of December 31, 2018 , the joint venture owned 14 office properties totaling 489,000 square feet. A cash sweep of net cash flow was required to be implemented under the mortgage loan encumbering such properties until such time as a loan-to-value milestone was satisfied. In lieu thereof, the joint venture and the bank agreed to a partial pay down of the mortgage loan in 2018. The Company had notes receivable from Kings Hill Unit Trust for an aggregate of $4.9 million and $4.7 million as of December 31, 2018 and 2017 , respectively. The note receivable bears interest at a rate of 10% and is due in November 2020. These related party receivables are reflected in investments in and advances to unconsolidated joint ventures in the Company's consolidated balance sheets. The Company had a receivable from Kings Hill Unit Trust for $15,000 and $122,000 as of December 31, 2018 and 2017, respectively. This related party receivable is reflected as prepaid expenses and other assets in the Company's consolidated balance sheets. The Company recognized $349,000 , $302,000 and $293,000 in fees for services during the years ended December 31, 2018 , 2017 and 2016 , respectively. Liberty Illinois, LP As of December 31, 2018 , the Company had a 25% interest in Liberty Illinois, LP, an entity primarily engaged in the ownership of industrial properties in Illinois. This joint venture is part of the Company's Chicago/Minneapolis reportable segment. As of December 31, 2018 , the joint venture owned 12 industrial properties totaling 4.9 million square feet and 248.0 acres of developable land. During the year ended December 31, 2016, the joint venture sold four properties containing 636,000 square feet for $32.5 million . The Company's share of gain on property dispositions was $1.0 million and is included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. The Company had a receivable from Liberty Illinois, LP for $331,000 and $5,000 as of December 31, 2018 and 2017, respectively. This related party receivable is reflected as prepaid expenses and other assets in the Company's consolidated balance sheets. The Company recognized $0.9 million , $0.9 million and $1.0 million in fees for services during the years ended December 31, 2018 , 2017 and 2016 , respectively. Liberty Washington, LP As of December 31, 2018 , the Company had a 25% interest in Liberty Washington, LP, an entity engaged in the ownership of office properties in Washington, D.C. This joint venture's properties are part of the Company's DC Metro reportable segment. As of December 31, 2018 , the joint venture owned two office properties totaling 451,000 square feet. During the year ended December 31, 2017, the Company concluded that a property owned by this joint venture had an indicator of impairment as it anticipated a shortened holding period, a major lease expiration and a significant capital investment. In addition, during 2018 the Company concluded that the property was further impaired. The 2018 impairment resulted from a decline in the Washington DC market fundamentals. The joint venture recognized impairment charges of $25.4 million and $15.9 million for the years ended December 31, 2018 and 2017, respectively. The Company's share of these impairment charges was $6.3 million and $4.0 million for the years ended December 31, 2018 and 2017, respectively. The impairment charges were related to the Company's DC Metro reportable segment and the Company's share was included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. The Company determined these impairments based on estimated future discounted cash flows. This is a Level 3 fair value calculation. During the year ended December 31, 2016, the joint venture sold 12 properties located in Northern Virginia containing 1.2 million square feet and 6.0 acres of land for $187.2 million . During the year ended December 31, 2016, due to adverse conditions in the Northern Virginia office market, six properties containing 698,000 square feet were transferred to mortgage lenders in satisfaction of an aggregate of $112.5 million in nonrecourse mortgage loans that were secured by the properties. The book values of these properties had been written down to fair value in prior periods. The Company's share of gain from property dispositions and extinguishment of debt is included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. During the year ended December 31, 2016, the Company's share of gain from extinguishment of debt was $4.2 million . The Company's share of gain on property dispositions for the year ended December 31, 2016 was $6.0 million . The Company had a receivable from Liberty Washington, LP for $1,000 and $316,000 as of December 31, 2018 and 2017 , respectively. This related party receivable is reflected as prepaid expenses and other assets in the Company's consolidated balance sheets. The Company recognized $1.2 million , $1.1 million and $2.0 million in fees for services during the years ended December 31, 2018 , 2017 and 2016 , respectively. Liberty/Comcast 1701 JFK Boulevard, LP As of December 31, 2018 , the Company had a 20% interest in Liberty/Comcast 1701 JFK Boulevard LP ("Liberty/Comcast") an entity engaged in the ownership of a 1.26 million square foot office tower in Philadelphia, Pennsylvania. This joint venture is part of the Company's Philadelphia reportable segment. During the year ended December 31, 2018, this joint venture paid in full its $305.2 million mortgage loan. The payment was funded through loans from the joint venture partners in proportion to their ownership interests. The Company's portion of the loan to the joint venture was $60.8 million as of December 31, 2018 and is included in investments in and advances to unconsolidated joint ventures in the Company's consolidated balance sheets. The Company had a payable to this joint venture for $59,000 as of December 31, 2018 and 2017 . This related party payable is reflected in investments in and advances to unconsolidated joint ventures in the Company's consolidated balance sheets. The Company had a receivable from this joint venture for $326,000 and $272,000 as of December 31, 2018 and 2017 , respectively. This related party receivable is reflected in prepaid expenses and other assets in the Company's consolidated balance sheets. The Company recognized $2.8 million , $2.7 million and $2.7 million in fees for services during the years ended December 31, 2018 , 2017 and 2016 , respectively. Liberty Property 18th & Arch LP and Liberty Property 18th & Arch Hotel, LP On June 30, 2014, the Company entered into two joint ventures for the purpose of developing and owning the Comcast Technology Center (the "Project") located in Philadelphia, Pennsylvania as part of a mixed-use development. The 60 -story building includes 1.3 million square feet of leasable office space (the "Office"), which is substantially complete, and will include a 217 -room Four Seasons Hotel (the "Hotel") (collectively, "Liberty Property 18th & Arch"). Project costs for the development of the Project, exclusive of tenant-funded interior improvements, are anticipated to be approximately $961.2 million . The Company's investment in the project is expected to be approximately $192.2 million with 20% ownership interests in both joint ventures. As of December 31, 2018 , the Company's investment in these joint ventures was $191.4 million and is reflected in investments in and advances to unconsolidated joint ventures in the Company's consolidated balance sheet. These joint ventures are part of the Company's Philadelphia reportable segment. During the year ended December 31, 2018, the joint venture owning the office portion of the Comcast Technology Center brought into service 250,000 square feet of office space representing a Total Investment by such joint venture of $136.1 million . During the year ended December 31, 2017, the joint venture owning the office portion of the Comcast Technology Center brought into service 1.1 million square feet of office space representing a Total Investment by such joint venture of $599.6 million . The office portion of the Project is now substantially complete. The 217 -room Four Seasons hotel representing an aggregate Total Investment by the joint venture owning the hotel portion of the Comcast Technology Center of $225.5 million when completed continued to be developed by such joint venture as of December 31, 2018. The two joint ventures have engaged the Company as the developer of the Project pursuant to a Development Agreement by which the Company agrees, in consideration for a development fee, to be responsible for all aspects of the development of the Project and to guarantee the timely lien-free completion of construction of the Project as well as the payment, subject to certain exceptions, of any cost overruns incurred in the development of the Project. To mitigate its risk, the Company entered into guaranteed maximum price contracts with a third party contractor (the "GMP Contracts") to construct the Project. The Company has been notified by its third-party contractor that the contractor has incurred cost overruns and expects to incur additional construction costs in connection with completing the Project in excess of the guaranteed maximum price payable to the contractor under the GMP Contracts, which guaranteed maximum price has been previously adjusted pursuant to accepted change orders. The Company intends to pursue all remedies to recover from the third-party contractor any amounts expended by the Company or the joint ventures in excess of their contractual obligations. However, the general contractor has generally refused to fund the additional costs, and the Company has begun to fund, and may continue to fund, cost overruns in compliance with its obligations under its development cost guarantee to the joint ventures. The Company has accrued such amounts as additional development service fee expense in its consolidated statements of comprehensive income for year ended December 31, 2018. As of December 31, 2018 and December 31, 2017, the Company had accrued $67.1 million and $5.6 million , respectively, relating to the above-described development cost guarantees which are included in other liabilities in the accompanying consolidated balance sheets. The Company is accounting for the development of the Project using the percentage of completion method. The Company recognized losses of $61.8 million and $3.5 million for the year ended December 31, 2018 and 2017, respectively, and income of $0.6 million for the year ended December 31, 2016 in developer service fee income, net of developer service fee expense and other related expenses. In addition to the costs to comply with the Company's obligations under its development cost guarantee, claims have been asserted by the third-party contractor and certain subcontractors. There can be no assurances that amounts incurred, including as a result of such claims, will not exceed the above estimates. The Company is not able to reasonably estimate the amount of additional expenses, if any, that it may incur as a result of such claims, and accordingly any potential exposure of the Company for such claims is not included within the accrual described above. If the Company were to incur additional expenses in connection with its development cost guarantee or in connection with such claims, such amounts would be accrued when they are determined to be probable of being incurred and are reasonably estimable, and could be material to the Company’s results of operations in future periods. If the Company were to subsequently recover any of the cost overruns initially funded by the Company, such recoveries would be recorded when and if realized in future periods. The Company had a receivable from this joint venture of $1.3 million and $466,000 as of December 31, 2018 and 2017, respectively. This receivable is included in prepaid expenses and other assets in the Company's consolidated balance sheets. During the year ended December 31, 2016, the joint venture sold three residential condominium units located on the 45 th floor containing 14,700 square feet for $14.3 million . The Company's share of gain on property dispositions was $0.3 million and is included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. The Company manages and leases the Office and Four Seasons Hotels Limited will manage the Hotel. The Company recognized $2.2 million, $230,000 and $75,000 in related fee income during the years ended December 31, 2018 , 2017 and 2016 , respectively. Other Joint Ventures As of December 31, 2018 , the Company had a 50% ownership interest in three additional unconsolidated joint ventures. One of these joint ventures has seven operating properties and an investment in land held for development and is part of the Company's Florida reportable segment. Another of these joint ventures sold its real estate assets in 2016 and was part of the Company's United Kingdom reportable segment. The sales price was $13.7 million and the Company's share of the loss on sale was $6,000 . This amount is included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. One joint venture has a leasehold interest and does not operate or own operating properties and is part of the Company's United Kingdom reportable segment. The Company had a note payable due to this joint venture of $2.4 million and $2.5 million as of December 31, 2018 and 2017 , respectively. The note payable is interest free and is due upon written notice from the joint venture. This related party payable is reflected in investments in and advances to unconsolidated joint ventures in the Company's consolidated balance sheets. Additionally, as of December 31, 2018, the Company had a 20% ownership interest in an unconsolidated joint venture that owns one redevelopment property comprising 48,000 square feet for $15.0 million . This joint venture also owns one acre of developable land and is part of the Company's Philadelphia reportable segment. The Company's share of each of the joint venture's earnings is included in equity in earnings of unconsolidated joint ventures in the accompanying consolidated statements of comprehensive income. Summary Financial Data The condensed balance sheets as of December 31, 2018 and 2017 and condensed statements of operations for the years ended December 31, 2018 , 2017 and 2016 for Liberty Venture I LP, Kings Hill Unit Trust, Liberty Illinois, LP, Liberty Washington LP, Liberty/Comcast, Liberty Property 18th & Arch, and the other unconsolidated joint ventures are as follows (in thousands): Condensed Balance Sheets: December 31, 2018 Liberty Kings Hill Liberty Liberty Liberty/ Liberty Property Venture I, LP Unit Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other Total Real estate assets $ 251,648 $ 144,742 $ 252,751 $ 210,732 $ 497,623 $ 688,537 $ 98,659 $ 2,144,692 Accumulated depreciation (54,373 ) (30,554 ) (61,593 ) (15,009 ) (152,169 ) (21,160 ) (12,991 ) (347,849 ) Real estate assets, net 197,275 114,188 191,158 195,723 345,454 667,377 85,668 1,796,843 Development in progress — — — — — 192,568 7,675 200,243 Land held for development — — 33,769 — — — 39,728 73,497 Other assets 23,180 12,141 14,662 17,146 43,671 152,845 29,085 292,730 Total assets $ 220,455 $ 126,329 $ 239,589 $ 212,869 $ 389,125 $ 1,012,790 $ 162,156 $ 2,363,313 Debt $ 170,743 $ 84,691 $ 138,964 $ 101,532 $ — $ — $ 74,081 $ 570,011 Related party debt — 20,239 — — 304,000 — — 324,239 Other liabilities 3,782 8,537 7,304 3,719 8,292 118,953 9,014 159,601 Equity 45,930 12,862 93,321 107,618 76,833 893,837 79,061 1,309,462 Total liabilities and equity $ 220,455 $ 126,329 $ 239,589 $ 212,869 $ 389,125 $ 1,012,790 $ 162,156 $ 2,363,313 Company's net investment in unconsolidated joint ventures (1) $ 9,516 $ 6,230 $ 13,863 $ 27,020 $ 75,102 $ 191,430 $ 27,820 $ 350,981 December 31, 2017 Liberty Kings Hill Liberty Liberty Liberty/ Liberty Property Venture I, LP Unit Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other Total Real estate assets $ 229,600 $ 152,998 $ 252,593 $ 274,847 $ 496,210 $ 551,874 $ 98,589 $ 2,056,711 Accumulated depreciation (48,629 ) (30,028 ) (57,444 ) (49,106 ) (138,943 ) (4,070 ) (10,995 ) (339,215 ) Real estate assets, net 180,971 122,970 195,149 225,741 357,267 547,804 87,594 1,717,496 Development in progress 18,337 — — — — 289,767 — 308,104 Land held for development — — 33,500 — — — 41,075 74,575 Other assets 20,722 10,957 16,337 18,566 49,755 98,191 24,263 238,791 Total assets $ 220,030 $ 133,927 $ 244,986 $ 244,307 $ 407,022 $ 935,762 $ 152,932 $ 2,338,966 Debt $ 166,295 $ 92,131 $ 138,869 $ 102,624 $ 305,223 $ — $ 63,999 $ 869,141 Related party debt — 21,435 — — — — — 21,435 Other liabilities 4,117 6,621 7,548 4,954 9,488 102,982 8,420 144,130 Equity 49,618 13,740 98,569 136,729 92,311 832,780 80,513 1,304,260 Total liabilities and equity $ 220,030 $ 133,927 $ 244,986 $ 244,307 $ 407,022 $ 935,762 $ 152,932 $ 2,338,966 Company's net investment in unconsolidated joint ventures (1) $ 10,425 $ 6,100 $ 14,980 $ 34,107 $ 17,307 $ 177,843 $ 27,694 $ 288,456 Condensed Statements of Operations: Year Ended December 31, 2018 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 30,310 $ 13,925 $ 24,729 $ 25,713 $ 71,389 $ 74,309 $ 14,563 $ 254,938 Operating expense (7,947 ) (5,150 ) (7,874 ) (9,496 ) (32,404 ) (20,240 ) (4,373 ) (87,484 ) Interest (6,184 ) (2,713 ) (4,771 ) (4,418 ) (425 ) — (3,403 ) (21,914 ) Related party interest — — — — (13,418 ) — (13,418 ) Depreciation and amortization (7,747 ) (3,577 ) (7,014 ) (5,513 ) (14,285 ) (17,184 ) (2,902 ) (58,222 ) Other income (expense) (16 ) (196 ) (56 ) (68 ) (436 ) (3,982 ) 11,265 6,511 Gain (loss) on sale/impairment — — — (25,389 ) — — — (25,389 ) Net income (loss) $ 8,416 $ 2,289 $ 5,014 $ (19,171 ) $ 10,421 $ 32,903 $ 15,150 $ 55,022 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,540 $ 602 $ 1,752 $ (4,189 ) $ 5,499 $ 7,126 $ 8,052 $ 21,382 Year Ended December 31, 2017 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 31,079 $ 12,976 $ 23,711 $ 25,439 $ 65,372 $ 16,544 $ 11,118 $ 186,239 Operating expense (8,101 ) (4,756 ) (7,989 ) (9,147 ) (26,474 ) (3,417 ) (3,365 ) (63,249 ) Interest (5,801 ) (2,329 ) (5,882 ) (4,065 ) (19,411 ) — (2,807 ) (40,295 ) Depreciation and amortization (7,598 ) (3,238 ) (6,918 ) (5,926 ) (14,485 ) (4,077 ) (2,124 ) (44,366 ) Other income (expense) (100 ) (4 ) (71 ) (65 ) (325 ) (547 ) 15,549 14,437 Gain (loss) on sale/impairment — — — (15,910 ) — 30 — (15,880 ) Net income (loss) $ 9,479 $ 2,649 $ 2,851 $ (9,674 ) $ 4,677 $ 8,533 $ 18,371 $ 36,886 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,914 $ 660 $ 2,118 $ (1,941 ) $ 1,659 $ 1,782 $ 9,963 $ 17,155 Year Ended December 31, 2016 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 25,149 $ 11,926 $ 26,599 $ 39,727 $ 65,587 $ — $ 9,888 $ 178,876 Operating expense (6,835 ) (4,854 ) (9,961 ) (15,935 ) (26,761 ) (280 ) (2,801 ) (67,427 ) Interest (4,182 ) (2,554 ) (7,243 ) (10,866 ) (19,737 ) — (2,462 ) (47,044 ) Depreciation and amortization (6,375 ) (3,557 ) (7,589 ) (10,750 ) (14,513 ) — (1,925 ) (44,709 ) Other income (expense) 50 (77 ) 64 257 (213 ) 1,270 7,123 8,474 Gain (loss) on sale/impairment — — 4,068 40,943 — — (11 ) 45,000 Net income (loss) $ 7,807 $ 884 $ 5,938 $ 43,376 $ 4,363 $ 990 $ 9,812 $ 73,170 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,332 $ 275 $ 2,065 $ 10,857 $ 1,594 $ 213 $ 4,634 $ 21,970 (1) Differences between the Company's net investment in unconsolidated joint ventures and its underlying equity in the net assets of the venture are primarily a result of impairments related to the Company's investment in unconsolidated joint ventures, the deferral of gains associated with the sales of properties to joint ventures in which the Company retains an ownership interest and loans made to the joint ventures by the Company. These adjustments have resulted in an aggregate difference reducing the Company's investments in unconsolidated joint ventures by $65.4 million and $3.0 million as of December 31, 2018 and 2017 , respectively. Differences between historical cost basis and the basis reflected at the joint venture level (other than loans) are typically depreciated over the life of the related asset. (2) Represents the combined results two joint ventures related to the property at 18th and Arch Streets, Philadelphia. (3) Other income/(expense) for this group of joint ventures reflects gains related to the sales of land leasehold interests totaling $11.5 million , $16.0 million and $7.1 million for the years ended December 31, 2018, 2017 and 2016, respectively.

Deferred Financing and Leasing

Deferred Financing and Leasing Costs	12 Months Ended
	Dec. 31, 2018
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Deferred Financing and Leasing Costs	DEFERRED FINANCING AND LEASING COSTS Deferred financing and leasing costs were comprised of the following as of December 31, 2018 and 2017 (in thousands): December 31, 2018 2017 Deferred financing costs $ 19,598 $ 17,044 Deferred leasing costs 203,609 175,656 Market value intangible 18,071 18,802 Origination value intangible 96,529 90,116 337,807 301,618 Accumulated amortization: Deferred financing costs 13,217 11,002 Deferred leasing costs 84,806 69,118 Market value intangible 14,611 14,324 Origination value intangible 56,434 59,719 169,068 154,163 Deferred financing and leasing costs, net $ 168,739 $ 147,455 Amortization of deferred financing costs was $3.8 million , $3.8 million and $4.0 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Amortization of deferred leasing costs and origination value intangible was $30.0 million , $31.6 million and $37.1 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. As of December 31, 2018 , the remaining weighted-average amortization period was 2.1 years for market value intangible and 4.2 years for origination value intangible. The table above includes market value intangible assets. There were also $11.2 million and $9.6 million of unamortized market value intangible liabilities as of December 31, 2018 and 2017 , respectively. These liabilities are included as other liabilities in the accompanying consolidated balance sheets of the Company. Amortization of the aggregate asset and liability for market value intangible was income of $45,000 for the year ended December 31, 2018 and expense of $1.3 million and $1.6 million for the years ended December 31, 2017 , and 2016 , respectively. The amount for the year ended December 31, 2018 was an increase in rental revenue and the amounts for the years ended December 31, 2017 and 2016 were included as a decrease in rental revenue in the accompanying consolidated statements of comprehensive income. The aggregate amortization of net market value intangible assets and liabilities is a decrease (increase) in rental revenue over the next five years and thereafter as follows (in thousands): 2019 $ (435 ) 2020 (1,224 ) 2021 (1,128 ) 2022 (1,177 ) 2023 (638 ) Thereafter (3,121 ) Total $ (7,723 ) The aggregate amortization expense for origination value intangible asset for the next five years and thereafter is as follows (in thousands): 2019 $ 12,345 2020 7,674 2021 6,315 2022 4,063 2023 2,498 Thereafter 7,200 Total $ 40,095

Indebtedness

Indebtedness	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Indebtedness	INDEBTEDNESS Overview Indebtedness consists of mortgage loans, unsecured notes, and borrowings under the Company's Credit Facilities (see below). The weighted average interest rates for the years ended December 31, 2018 , 2017 and 2016 were 3.8% , 3.8% and 4.3% , respectively. Interest costs during the years ended December 31, 2018 , 2017 and 2016 in the amount of $24.5 million , $21.0 million and $24.1 million , respectively, were capitalized. Cash paid for interest for the years ended December 31, 2018 , 2017 and 2016 was $118.4 million , $111.8 million and $142.7 million , respectively. The Company is subject to financial covenants contained in some of its debt agreements, the most restrictive of which are detailed below under the heading "Credit Facilities." As of December 31, 2018 , the Company was in compliance with all financial and non-financial covenants. The scheduled principal amortization and maturities of the Company's mortgage loans, unsecured notes outstanding and the Credit Facilities (as defined below) and the related weighted average interest rates at December 31, 2018 are as follows (in thousands, except percentages): Weighted Mortgages Average Principal Principal Unsecured Credit Interest Amortization Maturities Notes Facilities Total Rate 2019 $ 6,504 $ 50,043 $ — $ — $ 56,547 4.0 % 2020 3,539 67,361 350,000 — 420,900 4.7 % 2021 2,504 65,009 — 411,846 479,359 3.5 % 2022 2,172 — 400,000 — 402,172 4.1 % 2023 2,281 — 300,000 — 302,281 3.4 % 2024 2,395 — 450,000 — 452,395 4.4 % 2025 2,503 — 400,000 — 402,503 3.8 % 2026 2,494 1,946 400,000 — 404,440 3.3 % 2027 2,617 — — — 2,617 4.8 % 2028 and thereafter 17,183 165,229 — — 182,412 2.9 % Subtotal $ 44,192 $ 349,588 $ 2,300,000 $ 411,846 $ 3,105,626 3.8 % Reconciling items (1) 1,422 — (14,302 ) — (12,880 ) Total for consolidated balance sheet $ 45,614 $ 349,588 $ 2,285,698 $ 411,846 $ 3,092,746 (1) Includes deferred financing costs, premium/discount and market adjustments. Mortgage Loans and Unsecured Notes Mortgage loans with maturities ranging from 2019 to 2033 were collateralized by and in some instances cross-collateralized by properties with a net book value of $478.7 million as of December 31, 2018 . The interest rates on $2,693.8 million of mortgage loans (including $66.8 million fixed via a swap arrangement - see Footnote 20 - Derivative Instruments) and unsecured notes are fixed and range from 2.6% to 4.8% . The weighted average remaining term for the mortgage loans and unsecured notes is 5.1 years. Credit Facilities The Company has maintained an unsecured credit facility throughout 2016 , 2017 and 2018 . During that period the Company has replaced, restated and amended its credit facility. This activity has resulted in changes to borrowing capacity, due dates, borrowing costs and covenant calculations. As replaced, restated and amended these credit facilities are referred to below as the "Credit Facility." The Credit Facility includes a revolving credit facility for aggregate borrowings of $800 million and a delayed draw term loan facility for aggregate borrowings of $100 million . The interest rate on borrowings under the Credit Facility fluctuates based upon ratings from Moody’s Investors Service, Inc., Standard and Poor’s Ratings Group and Fitch, Inc. Based on the Company's ratings as of December 31, 2018, borrowings under the revolving credit facility currently bear interest at LIBOR plus 0.875% and the delayed draw term loan facility bear interest at LIBOR plus 0.95% . The revolving credit facility also contains an annual facility fee, the rate of which is currently 0.15% of the aggregate loan commitments. The Credit Facility provides for the interest rate and facility fee rate to be adjusted up or down based on changes in the credit ratings on the Company's senior unsecured debt. The Credit Facility expires in October 2021 and has two six -month extensions at the Company's option, subject to the payment of a stated fee. The Credit Facility contains a competitive bid option, whereby participating lenders bid on the interest rate to be charged. This feature is available for up to 50% of the amount of the revolving credit facility. There were $310.0 million borrowings outstanding under the revolving credit facility and $100.0 million borrowings under the delayed draw term loan facility as of December 31, 2018. As of December 31, 2018, letters of credit to third parties totaling $8.3 million had been issued for the account of the Company under this Credit Facility. The Credit Facility contains financial covenants, certain of which are set forth below: • total debt to total assets may not exceed 0.60 : 1 ; • adjusted earnings before interest, taxes, depreciation and amortization to fixed charges may not be less than 1.50 :1; • unsecured debt to unencumbered asset value must equal or be less than 60% • secured debt to total asset value must equal or be less than 35% ; and • unencumbered adjusted net operating income to unsecured interest expense must equal or exceed 175% . In October 2017, the Company entered into a credit agreement for a working capital facility for aggregate borrowings of up to $30 million . This facility has the same maturity date, facility fee, covenants and interest rate borrowing terms as the revolving credit facility described above. There were $1.8 million in borrowings outstanding under the working capital facility as of December 31, 2018. Activity In September 2016, the Company issued $400 million of 3.25% senior unsecured notes due 2026. The Company used a substantial portion of the net proceeds from these notes and the proceeds from asset sales to prepay its 5.5% senior notes due December 2016 in the amount of $300 million , its 6.625% senior notes due October 2017 in the amount of $296.5 million and its 7.5% medium term notes due January 2018 in the amount of $100.0 million . This prepayment resulted in a $27.1 million loss on debt extinguishment. In October 2017, the Company replaced its existing $800 million Credit Facility with a new $800 million revolving credit facility and a $100 million delayed draw term loan facility. Additionally, the Company entered into a working capital facility for aggregate borrowings of up to $30 million . In December 2018, the Company entered into a £129.5 million mortgage loan secured by properties in the Company's United Kingdom reportable segment at an interest rate of 2.64% . In January 2019, the Company issued $350 million of 4.375% senior unsecured notes due 2029. The Company used the proceeds to pay down its revolving credit facilities. See Note 22 - Subsequent Events.

Leasing Activity

Leasing Activity	12 Months Ended
	Dec. 31, 2018
Operating Leases, Future Minimum Payments Receivable [Abstract]
Leasing Activity	LEASING ACTIVITY Future minimum rental payments due from tenants under noncancelable operating leases as of December 31, 2018 are as follows (in thousands): 2019 $ 499,382 2020 449,258 2021 381,385 2022 313,556 2023 244,783 Thereafter 1,059,713 Total $ 2,948,077 In addition to minimum rental payments, most leases require the tenants to pay for their pro rata share of specified operating expenses. These payments are included as operating expense reimbursement in the accompanying consolidated statements of comprehensive income.

Noncontrolling Interest - Opera

Noncontrolling Interest - Operating Partnership/Limited Partners' Equity - Preferred Units	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest - Operating Partnership / LImited Partners' Equity - Preferred Units [Abstract]
Noncontrolling Interest - Operating Partnership/Limited Partners' Equity - Preferred Units	NONCONTROLLING INTEREST - OPERATING PARTNERSHIP / LIMITED PARTNERS' EQUITY - PREFERRED UNITS As of December 31, 2018 , the Company had outstanding the following cumulative preferred units of the Operating Partnership: ISSUE AMOUNT UNITS LIQUIDATION PREFERENCE DIVIDEND RATE (in 000’s) Series I-2 $ 7,537 301 $25 6.25 % The preferred units are putable at the holder's option at any time and are callable at the Operating Partnership's option after a stated period of time for cash. Preferred distributions related to the Series I units were $472,000 for each of the years ended December 31, 2018 , 2017 and 2016 .

Shareholders' Equity - Trust

Shareholders' Equity - Trust	12 Months Ended
	Dec. 31, 2018
Shareholders' Equity [Abstract]
Shareholders' Equity - Trust	SHAREHOLDERS' EQUITY - TRUST Common Shares The Company paid to holders of its common shares and holders of its common units distributions of $241.8 million , $252.3 million and $285.9 million during the years ended December 31, 2018 , 2017 and 2016 , respectively. On a per share basis, the Company paid common share and common unit distributions of $1.60 , $1.675 and $1.90 during the years ended December 31, 2018, 2017 and 2016 , respectively. The following unaudited table summarizes the taxability of common share distributions (taxability for 2018 is estimated): 2018 2017 2016 Ordinary dividend $ 1.3676 $ 1.5369 $ 1.0319 Qualified dividend — 0.0150 0.0013 Capital gain - 20% 0.0928 0.0482 — IRC Sec 1250 unrecaptured gain - 25% 0.1396 0.0749 0.6176 Return of capital — — 0.2492 Total $ 1.6000 $ 1.6750 $ 1.9000 The Company's tax return for the year ended December 31, 2018 has not been filed. The taxability information presented for the 2018 distributions is based upon the best available data at the time of this filing. In addition, certain of the Company's prior federal income tax returns may still be subject to examination by various taxing authorities. Because the application of tax laws and regulations is susceptible to varying interpretations, the taxability of distributions being reported here could be changed at a later date as a result of an examination and final determination by such taxing authorities. Common units The common units of the Operating Partnership not held by the Trust outstanding as of December 31, 2018 have the same economic characteristics as common shares of the Trust. The 3,520,205 outstanding common units of the Operating Partnership not held by the Trust share proportionately in the net income or loss and in any distributions of the Operating Partnership. The common units of the Operating Partnership not held by the Trust are redeemable at any time at the option of the holder. The Trust, as the sole general partner of the Operating Partnership, may at its option elect to settle the redemption in cash or through the exchange on a one -for- one basis with unregistered common shares of the Trust. The market value of the 3,520,205 outstanding common units based on the closing price of the common shares of the Company at December 31, 2018 was $ 147.4 million . No common units were issued in connection with acquisitions during 2018 , 2017 or 2016 . Dividend Reinvestment and Share Purchase Plan The Company has a Dividend Reinvestment and Share Purchase Plan under which holders of common shares may elect to automatically reinvest their distributions in additional common shares and may make optional cash payments for additional common shares. The Company may issue additional common shares or repurchase common shares in the open market for purposes of satisfying its obligations under the Dividend Reinvestment and Share Purchase Plan. During the years ended December 31, 2018 , 2017 , and 2016 , 36,807 , 42,366 , and 56,426 common shares, respectively, were issued through the Dividend Reinvestment and Share Purchase Plan. The Company used the proceeds to pay down outstanding borrowings under the Company's Credit Facility and for general corporate purposes. Continuous Equity Offering The Company has a continuous equity offering program in place for up to $200 million of equity, of which $125.0 million remains available. The Company did no t sell any common shares pursuant to its continuous equity offering program during 2018, 2017 or 2016. Noncontrolling Interest - Consolidated Joint Ventures Noncontrolling interest - consolidated joint ventures includes third-party ownership interests in consolidated joint venture investments. Share Repurchase In September 2017, the Company’s Board of Trustees authorized a share repurchase plan under which the Company may purchase up to $250 million of the Company’s outstanding common shares through September 2019. Purchases made pursuant to the program will be made in either the open market or in privately negotiated transactions from time to time as permitted by securities laws and other legal requirements. During the year ended December 31, 2016, the Company purchased an aggregate of 1.4 million common shares for $40.9 million as part of a previously authorized share repurchase plan. There were no share repurchases under this plan or the current plan in 2017 or 2018.

Owners' Equity - Operating Part

Owners' Equity - Operating Partnership	12 Months Ended
	Dec. 31, 2018
Liberty Property Limited Partnership
Class of Stock [Line Items]
Owners' Equity - Operating Partnership	OWNERS' EQUITY - OPERATING PARTNERSHIP Common Units General and limited partners' equity - common units relates to limited partnership interests of the Operating Partnership issued in connection with the formation of the Operating Partnership and certain subsequent acquisitions. The common units outstanding as of December 31, 2018 have the same economic characteristics as common shares of the Trust. The 3,520,205 outstanding common units are the limited partners' equity - common units held by persons and entities other than the Trust, the general partner of the Operating Partnership, which holds a number of common units equal to the number of outstanding common shares of beneficial interest. Both the common units held by the Trust and the common units held by persons and entities other than the Trust are counted in the weighted average number of common units outstanding during any given period. The 3,520,205 outstanding common units share proportionately in the net income or loss and in any distributions of the Operating Partnership and are exchangeable into the same number of common shares of the Trust. The market value of the 3,520,205 outstanding common units at December 31, 2018 based on the closing price of the common shares of the Company at December 31, 2018 was $ 147.4 million . No common units were issued in connection with acquisitions during 2018 , 2017 or 2016 . Dividend Reinvestment and Share Purchase Plan The Company has a Dividend Reinvestment and Share Purchase Plan under which holders of common shares may elect to automatically reinvest their distributions in additional common shares and may make optional cash payments for additional common shares. The Company may issue additional common shares or repurchase common shares in the open market for purposes of satisfying its obligations under the Dividend Reinvestment and Share Purchase Plan. During the years ended December 31, 2018 , 2017 , and 2016 , 36,807 , 42,366 , and 56,426 common shares, respectively, were issued through the Dividend Reinvestment and Share Purchase Plan. A corresponding number of common units were issued by the Operating Partnership. The Company used the proceeds to pay down outstanding borrowings under the Company's existing credit facility and for general corporate purposes. Noncontrolling Interest - Consolidated Joint Ventures Noncontrolling interest - consolidated joint ventures includes third-party ownership interests in consolidated joint venture investments. Share Repurchase In September 2017, the Company’s Board of Trustees authorized a share repurchase plan under which the Company may purchase up to $250 million of the Company’s outstanding common shares through September 2019. Purchases made pursuant to the program will be made in either the open market or in privately negotiated transactions from time to time as permitted by securities laws and other legal requirements. During the year ended December 31, 2016, the Company purchased an aggregate of 1.4 million common shares for $40.9 million as part of a previously authorized share repurchase plan. In connection with these repurchases, an equal number of common units were repurchased by the Operating Partnership from the Trust. There were no share repurchases under this plan or the current plan in 2017 or 2018.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2018
Employee Benefit Plans [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS The Company maintains a 401(k) plan for the benefit of its employees. The Company matches the employees' contributions up to 3% of the employees' salary and may also make annual discretionary contributions. Total 401(k) expense recognized by the Company was $784,000 , $755,000 and $874,000 for the years ended December 31, 2018 , 2017 and 2016 , respectively.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2018
Share-based Compensation [Abstract]
Share-Based Compensation	SHARE-BASED COMPENSATION Compensation Plans The Company has a share-based compensation plan (the "Plan") which is utilized to compensate key employees and non-employee trustees. The plan was last amended and restated in 2014. Pursuant to the Plan, grants of stock options, restricted shares and restricted stock units have been made. The Company has authorized the grant of shares and options under the Plan of up to 21.1 million common shares of the Company. The Company capitalized $1.0 million , $1.1 million and $1.2 million in share-based compensation costs for the years ended December 31, 2018, 2017, and 2016, respectively. Options All options granted have a 10 -year term and most options vest and are expensed over a 3 -year period, with options to purchase up to 20% of the shares exercisable after the first anniversary, up to 50% after the second anniversary and 100% after the third anniversary of the date of grant. Share-based compensation cost related to options for the years ended December 31, 2018, 2017 and 2016 was $12,000 , $73,000 and $165,000 , respectively. A summary of the Company's share option activity and related information for the year ended December 31, 2018 follows: Options (000s) Weighted Average Exercise Price Outstanding January 1, 2018 1,581 $ 34.97 Exercised (151 ) 32.83 Outstanding December 31, 2018 1,430 $ 35.20 Exercisable at December 31, 2018 1,430 $ 35.20 No new options were granted during the years ended December 31, 2018, 2017 and 2016. Exercise prices for options outstanding as of December 31, 2018 ranged from $20.32 to $39.59 . At December 31, 2018 , the weighted average remaining contractual life of the options outstanding and exercisable was 4.0 years. During the years ended December 31, 2018 , 2017 and 2016 , the total intrinsic value of share options exercised (the difference between the market price at exercise and the price paid by the individual to exercise the option) was $1.4 million , $1.4 million and $3.5 million , respectively. As of December 31, 2018 , 1.4 million options outstanding and exercisable had an exercise price lower than the closing price of the Company's common shares. The aggregate intrinsic value of these options was $9.6 million at that date. The total cash received from the exercise of options for the years ended December 31, 2018 , 2017 and 2016 was $5.0 million , $6.7 million and $14.4 million , respectively. As of December 31, 2018 , there were no unrecognized compensation costs related to nonvested options granted under the Plan. Long Term Incentive Shares ("LTI") During January 2018, 2017 and 2016, restricted LTI share grants made under the Plan were valued at the grant date fair value, which is the market price of the underlying common shares. LTI share grants after February 2017 were valued at the average closing price of the Company's shares for the trading days included within the 30-calendar-day period prior to and including the date of grant. The shares vest over either a 3 -year or 5 -year period beginning with the first anniversary of the grant and subject to certain accelerated vesting due to the age and years of service of certain employees. During 2018 , 2017 and 2016 , the Company granted restricted stock units to the executive officers pursuant to the Plan. For the chief executive officer's 2016 and 2017 awards, a portion of the restricted stock units will vest up to 272% at the end of a 3 -year period. For the chief executive officer's 2018 award, a portion of the restricted stock units will vest up to 250% at the end of a 3 -year period. For the other executives, for awards in 2016, 2017 and 2018 a portion of the restricted stock units will vest up to 200% at the end of a 3 -year period. A portion ("First Portion") of the award vests based on how the Company's total return compares to the average total returns of a selected group of peer companies. The grant date fair value of the First Portion was calculated based on a Monte Carlo simulation model and was determined to be 149% , 132% and 174% of the market value of a common share as of the grant date ("Market Value") for the chief executive officer and 125% , 105% and 136% of the Market Value for the other executives for the 2018, 2017 and 2016 grants, respectively. A separate grant was made to the Company's Chief Financial Officer in 2016 when he joined the Company, and the grant date fair value of this award's First Portion was determined to be 160% of the Market Value as of the grant date. The First Portion is amortized over the respective 3 -year period subject to certain accelerated vesting due to the age and years of service of certain executive officers. For the 2016 and 2017 awards, the second portion of the award for the executive officers, other than the Chief Financial Officer's 2016 award, vests at the end of three years based on continued employment. The second portion of the Chief Financial Officer's award vests ratably over three years. For the 2017 award, the second portion of the award for the executive officers vests at the end of three years based on continued employment. The key assumptions used in the Monte Carlo simulations are as follows: Year Ended December 31, 2018 2017 2016 Risk-free interest rate 2.39% 1.43% 1.01% Volatility 19% 20% 19% The volatility factor is based on the Company's historical daily share prices. Share-based compensation cost related to restricted LTI share grants for the years ended December 31, 2018 , 2017 and 2016 was $11.1 million , $11.3 million and $12.2 million , respectively. The Company's restricted LTI share activity for the year ended December 31, 2018 is as follows: Shares (000s) Weighted Avg. Grant Date Fair value Nonvested at January 1, 2018 775 $ 36.43 Granted 343 39.89 Vested (292 ) 36.29 Forfeited (44 ) 37.85 Nonvested at December 31, 2018 782 $ 37.92 The weighted average fair value of restricted shares granted during the years ended December 31, 2018 , 2017 and 2016 was $39.89 , $39.93 and $32.48 per share, respectively. As of December 31, 2018 , there was $8.4 million of total unrecognized compensation cost related to nonvested shares granted under the Plan. That cost is expected to be recognized over a weighted average period of 1.2 years. The total fair value of restricted shares vested during the years ended December 31, 2018 , 2017 and 2016 was $10.6 million , $11.7 million and $9.0 million , respectively. Bonus Shares During the years ended December 31, 2018 , 2017 and 2016 , the Plan provided that employees of the Company could elect to receive bonuses or commissions in the form of common shares in lieu of cash ("Bonus Shares"). By making such election, the employee received shares equal to 120% of the cash value of the bonus or commission, for up to $50,000 of such bonus or commission, and 100% thereof for amounts exceeding $50,000 , in each case reduced by applicable withholding tax. Bonus Shares issued for the years ended December 31, 2018 , 2017 and 2016 were 41,620 , 51,416 and 140,376 , respectively. Share-based compensation cost related to Bonus Shares for the years ended December 31, 2018 , 2017 and 2016 was $1.7 million , $2.0 million and $4.7 million , respectively. Profit Sharing The Plan provides that employees of the Company, below the officer level, may receive up to 5% of base pay in the form of cash contributions to an investment account depending on Company performance. Compensation cost related to the profit sharing plan for the years ended December 31, 2018 , 2017 and 2016 was $706,000 , $730,000 and $669,000 , respectively. Remaining Reserved Common Shares under the Plan An additional 4,653,912 , 5,049,687 and 5,264,285 common shares were reserved for issuance for future grants under the Plan at December 31, 2018 , 2017 and 2016 , respectively. Employee Share Purchase Plan The Company registered 750,000 common shares under the Securities Act of 1933, as amended, in connection with an employee share purchase plan ("ESPP"). The ESPP enables eligible employees to purchase shares of the Company, in amounts up to 10% of the employee's salary, at a 15% discount to fair market value. There were 7,475 , 10,410 and 11,022 shares issued, in accordance with the ESPP, during the years ended December 31, 2018 , 2017 and 2016 , respectively. Share-based compensation cost related to the ESPP for the years ended December 31, 2018 , 2017 and 2016 was $87,502 , $80,000 and $122,000 , respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Environmental Matters Substantially all of the Company's properties and land were subject to Phase I Environmental Assessments and when appropriate Phase II Environmental Assessments (collectively, the “Environmental Assessments”) obtained in contemplation of their acquisition by the Company or obtained by predecessor owners prior to the sale of the property or land to the Company. The Environmental Assessments did not reveal, nor is the Company aware of, any non-compliance with environmental laws, environmental liability or other environmental claim that the Company believes would likely have a material adverse effect on the Company. Operating Ground Lease Agreements Future minimum rental payments under the terms of all non-cancelable operating ground leases under which the Company is the lessee, as of December 31, 2018 , were as follows (in thousands): Year Amount 2019 $ 961 2020 961 2021 961 2022 961 2023 961 2024 though 2067 34,194 Total $ 38,999 Operating ground lease expense incurred by the Company during the years December 31, 2018 , 2017 and 2016 totaled $1.5 million , $0.1 million and $1.0 million , respectively. Legal Matters From time to time, the Company is a party to a variety of legal proceedings, claims and assessments arising in the normal course of business. The Company believes that as of December 31, 2018 there were no legal proceedings, claims or assessments expected to have a material adverse effect on the Company’s business or financial statements. Other As of December 31, 2018 , the Company had letter of credit obligations of $8.3 million related to development requirements. The Company believes that it is remote that there will be a draw upon these letter of credit obligations. As of December 31, 2018 , the Company had 29 buildings under development. These buildings are expected to contain a total of 8.2 million square feet of leaseable space and represent an anticipated aggregate investment of $735.0 million . At December 31, 2018 , Development in Progress totaled $472.2 million . In addition, as of December 31, 2018 , the Company had invested $13.2 million in deferred leasing costs related to these development buildings. As of December 31, 2018 , the Company was committed to $13.0 million in improvements on certain buildings and land parcels. As of December 31, 2018 , the Company was obligated to pay for tenant improvements not yet completed for a maximum of $17.8 million . As of December 31, 2018 , the Company was committed to $49.5 million in future land purchases which it expects to complete during the year ended December 31, 2019. As of December 31, 2018, the Company was developing two buildings for its unconsolidated joint ventures which represented an anticipated aggregate investment by the joint ventures of $235.8 million . Two unconsolidated joint ventures in which the Company holds an interest have engaged the Company as the developer of the Comcast Technology Center (the “Project") pursuant to a Development Agreement by which the Company agrees, in consideration for a development fee, to be responsible for all aspects of the development of the Project and to guarantee the timely lien-free completion of construction of the Project as well as the payment, subject to certain exceptions, of any cost overruns incurred in the development of the Project. To mitigate its risk, the Company entered into guaranteed maximum price contracts with a third party contractor (the "GMP Contracts") to construct the Project. As discussed in Note 7, the Company has been notified by its third-party contractor that the contractor has incurred cost overruns and expects to incur additional construction costs in connection with completing the Project in excess of the guaranteed maximum price payable to the contractor under the GMP Contracts, which guaranteed maximum price has been previously adjusted pursuant to accepted change orders. The Company intends to pursue all remedies to recover from the third-party contractor any amounts expended by the Company or the joint ventures in excess of their contractual obligations. However, the general contractor has generally refused to fund these additional costs, and the Company has begun to fund and may continue to fund cost overruns in compliance with its obligations under its development cost guarantee to the joint ventures. As of December 31, 2018 and December 31, 2017, the Company had accrued $67.3 million and $5.6 million , respectively, relating to the above-described development cost guarantees which are included in other liabilities in the accompanying consolidated balance sheets. In addition to the costs to comply with the Company's obligations under its development cost guarantee, claims have been asserted by the third-party contractor and certain subcontractors. There can be no assurances that amounts incurred, including as a result of such claims, will not exceed the above estimates. The Company is not able to reasonably estimate the amount of additional expenses, if any, that it may incur as a result of such claims, and accordingly any potential exposure of the Company for such claims is not included within the accrual described above. If the Company were to incur additional expenses in connection with its development cost guarantee or in connection with such claims, such amounts would be accrued when they are determined to be probable of being incurred and are reasonably estimable, and could be material to the Company’s results of operations in future periods. If the Company were to subsequently recover any of the cost overruns initially funded by the Company, such recoveries would be recorded when and if realized in future periods. As of December 31, 2018, the Company was also committed to approximately $170.9 million in costs related to its agreement to develop, on a fee basis, an office building and infrastructure improvements for American Water Works in Camden, New Jersey. As of December 31, 2018, $159.2 million of these costs had been incurred. The Company maintains cash and cash equivalents at financial institutions. The combined account balances at each institution typically exceed FDIC insurance coverage and, as a result, there is a concentration of credit risk related to amounts on deposit in excess of FDIC insurance coverage. The Company believes the risk is not significant.

Quarterly Results of Operations

Quarterly Results of Operations (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations (Unaudited)	QUARTERLY RESULTS OF OPERATIONS (UNAUDITED) A summary of quarterly results of operations for the years ended December 31, 2018 and 2017 follows (in thousands, except for per share data): QUARTER ENDED DEC. 31, SEPT. 30, JUNE 30, MAR. 31, DEC. 31, SEPT. 30, JUNE 30, MAR. 31, 2018 2018 2018 2018 2017 2017 2017 2017 Total revenue $ 180,281 $ 170,389 $ 174,091 $ 180,128 $ 179,825 $ 170,783 $ 160,747 $ 154,029 Income from continuing operations 58,084 49,740 12,942 45,299 109,245 57,770 44,460 37,331 Discontinued operations 115,832 104,332 7,948 98,426 22,579 3,389 8,358 6,913 Net income 173,916 154,072 20,890 143,725 131,824 61,159 52,818 44,244 Income per common share - basic (1) 1.15 1.02 0.13 0.95 0.87 0.41 0.35 0.29 Income per common share - diluted (1) 1.14 1.01 0.13 0.95 0.87 0.40 0.35 0.29 (1) The sum of quarterly financial data may vary from the annual data due to rounding.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Information	SEGMENT INFORMATION The Company owns and operates industrial properties nationally and owns and operates office properties in a focused group of office markets. Additionally, the Company owns certain assets in the United Kingdom. At December 31, 2018 , the Company's reportable segments were based on the Company's method of internal reporting and were as follows: • Carolinas/Richmond; • Chicago/Minneapolis; • Florida; • Houston; • Lehigh/Central PA; • Philadelphia; • Southeastern PA; • Southern California; and • United Kingdom. Certain other segments are aggregated into an "Other" category which includes the reportable segments: Arizona; Atlanta; Cincinnati/Columbus/Indianapolis; Dallas; DC Metro; and New Jersey. Comparative prior periods have been restated to reflect current segment disclosures. The Company evaluates the performance of its reportable segments based on net operating income. Net operating income includes operating revenue from external customers, real estate taxes, amortization of lease transaction costs and other operating expenses which relate directly to the management and operation of the assets within each reportable segment. The Company's accounting policies for the segments are the same as those used in the Company's consolidated financial statements. There are no material inter-segment transactions. The operating information by reportable segment is as follows (in thousands): Year ended December 31, 2018 2017 2016 Operating revenue Carolinas/Richmond $ 79,271 $ 74,158 $ 66,270 Chicago/Minneapolis 67,551 64,706 84,028 Florida 64,486 59,526 99,733 Houston 64,968 59,957 59,582 Lehigh/Central PA 156,629 163,026 141,046 Philadelphia 44,387 45,504 41,838 Southeastern PA 27,874 59,762 91,656 Southern California 30,939 13,856 11,019 United Kingdom 17,193 13,917 13,376 Other 134,553 116,868 125,502 Segment-level operating revenue 687,851 671,280 734,050 Reconciliation to total operating revenues Development service fee income (1) 73,224 82,673 12,941 Discontinued operations (56,056 ) (88,429 ) (71,385 ) Other (130 ) (140 ) (283 ) Total operating revenue $ 704,889 $ 665,384 $ 675,323 Net operating income Carolinas/Richmond $ 57,105 $ 53,132 $ 46,170 Chicago/Minneapolis 40,781 39,231 45,258 Florida 44,204 39,850 62,177 Houston 37,766 32,300 32,499 Lehigh/Central PA 114,201 119,304 102,209 Philadelphia 36,216 35,279 30,862 Southeastern PA 20,044 35,641 53,947 Southern California 24,360 10,199 7,079 United Kingdom 8,996 7,657 6,390 Other 86,638 75,928 82,195 Segment-level net operating income 470,311 448,521 468,786 Reconciliation to income from continuing operations Interest expense (2) (95,442 ) (91,096 ) (115,077 ) Loss on debt extinguishment — (49 ) (27,099 ) Development service fee income 73,224 82,673 12,941 Development service fee expense (134,825 ) (85,805 ) (12,165 ) Depreciation/amortization expense (2) (3) (129,048 ) (132,613 ) (152,556 ) Impairment - real estate assets (2) (39,688 ) (10,632 ) (3,879 ) Gain on property dispositions 81,514 100,387 219,270 Equity in earnings of unconsolidated joint ventures 21,382 17,155 21,970 General and administrative expense (2) (3) (37,278 ) (39,024 ) (40,090 ) Other operating expenses (3) (10,835 ) (5,294 ) (4,418 ) Discontinued operations excluding gain on property dispositions (23,379 ) (26,661 ) (27,129 ) Income taxes (3) (4,701 ) (240 ) 47 Other (4) (5,170 ) (8,516 ) (1,585 ) Income from continuing operations $ 166,065 $ 248,806 $ 339,016 (1) Prior to the fourth quarter of 2016, development service fee income had been classified as other income and development service fee expense had been classified as general and administrative expense. See Note 2. (2) Includes activity in discontinued operations. (3) Excludes costs which are included in determining segment-level net operating income. (4) Includes severance activity in segment-level net operating income. The amount of depreciation and amortization expense related to tenant improvement and lease transaction costs within each reporting segment for the net operating income calculation is as follows (in thousands): Year ended December 31, 2018 2017 2016 Carolinas/Richmond $ 5,445 $ 5,205 $ 4,944 Chicago/Minneapolis 4,912 4,393 5,858 Florida 4,050 4,174 6,605 Houston 4,898 5,155 4,713 Lehigh/Central PA 13,121 14,475 12,262 Philadelphia 2,626 2,797 2,706 Southeastern PA 630 3,617 6,134 Southern California 850 612 367 United Kingdom 384 340 259 Other 9,109 8,509 8,687 Depreciation and amortization of tenant improvement and lease transaction costs $ 46,025 $ 49,277 $ 52,535 The Company's operating revenue by product type and by reportable segment for the years ended December 31, 2018 , 2017 and 2016 is as follows (in thousands): Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Industrial Office Total Industrial Office Total Industrial Office Total Carolinas/Richmond $ 79,271 $ — $ 79,271 $ 74,158 $ — $ 74,158 $ 66,270 $ — $ 66,270 Chicago/Minneapolis 63,393 4,158 67,551 60,826 3,880 64,706 65,007 19,021 84,028 Florida 61,878 2,608 64,486 56,923 2,603 59,526 66,028 33,705 99,733 Houston 64,968 — 64,968 58,606 1,351 59,957 58,370 1,212 59,582 Lehigh/Central PA 156,629 — 156,629 163,026 — 163,026 138,766 2,280 141,046 Philadelphia 11,923 32,464 44,387 11,914 33,590 45,504 12,842 28,996 41,838 Southeastern PA 4,139 23,735 27,874 8,925 50,837 59,762 19,448 72,208 91,656 Southern California 30,939 — 30,939 13,856 — 13,856 11,019 — 11,019 United Kingdom 13,601 3,592 17,193 10,369 3,548 13,917 10,775 2,601 13,376 Other 105,622 28,931 134,553 88,601 28,267 116,868 80,743 44,759 125,502 $ 592,363 $ 95,488 687,851 $ 547,204 $ 124,076 671,280 $ 529,268 $ 204,782 734,050 Reconciliation to total operating revenue Development service fee income 73,224 82,673 12,941 Discontinued operations (56,056 ) (88,429 ) (71,385 ) Corporate other (130 ) (140 ) (283 ) Total operating revenue $ 704,889 $ 665,384 $ 675,323 The Company's total assets by reportable segment as of December 31, 2018 and 2017 is as follows (in thousands): As of December 31, 2018 2017 Carolinas/Richmond $ 525,041 $ 543,922 Chicago/Minneapolis 591,792 615,186 Florida 547,232 533,861 Houston 568,756 498,584 Lehigh/Central PA 1,210,220 1,210,746 Philadelphia 624,373 665,843 Southeastern PA 48,827 241,128 Southern California 660,688 362,122 United Kingdom 463,162 251,824 Other 1,497,629 1,445,531 Segment-level total assets 6,737,720 6,368,747 Corporate Other 196,674 71,010 Total assets $ 6,934,394 $ 6,439,757 The Company's real estate assets by reportable segment as of December 31, 2018 and 2017 is as follows (in thousands): As of December 31, 2018 2017 Carolinas/Richmond $ 495,149 $ 491,916 Chicago/Minneapolis 545,919 557,782 Florida 492,797 483,355 Houston 509,100 456,675 Lehigh/Central PA 1,151,148 1,121,115 Philadelphia 286,568 279,338 Southeastern PA 15,467 19,357 Southern California 633,450 343,520 United Kingdom 347,886 191,552 Other 1,228,447 1,004,667 Total real estate assets $ 5,705,931 $ 4,949,277 The Company incurred the following costs related to its long-lived assets for the years ended December 31, 2018 , 2017 and 2016 (in thousands): Year Ended December 31, 2018 2017 2016 Costs incurred on long-lived assets Carolinas/Richmond $ 22,220 $ 31,958 $ 51,647 Chicago/Minneapolis 3,326 14,246 29,317 Florida 41,967 23,832 38,312 Houston 77,323 17,522 25,831 Lehigh/Central PA 63,926 89,304 176,386 Philadelphia 3,326 30,685 57,691 Southeastern PA 5,118 9,737 4,824 Southern California 298,580 183,842 5,599 United Kingdom 165,276 10,501 11,492 Other 240,476 220,411 101,901 Total costs incurred on long-lived assets $ 921,538 $ 632,038 $ 503,000

Accounting for the Impairment o

Accounting for the Impairment or Disposal of Long-Lived Assets	12 Months Ended
	Dec. 31, 2018
Accounting for the Impairment or Disposal of Long-Lived Assets [Abstract]
Accounting for the Impairment or Disposal of Long-Lived Assets	ACCOUNTING FOR THE IMPAIRMENT OR DISPOSAL OF LONG-LIVED ASSETS In 2017, the Company initiated a strategic shift whereby it plans to divest of its remaining suburban office properties. In 2018, the Company updated its strategy whereby it plans to divest of its remaining office properties. The Company determined that the strategic shift would have a major effect on its operations and financial results. As such, properties sold or those that meet the criteria to be classified as held for sale within the new corporate strategy were classified within discontinued operations. Consistent with the held for sale criteria these properties are expected to be sold within one year. As the result of the classification within discontinued operations, the in-service assets and liabilities of this portfolio are required to be presented as held for sale for all prior periods presented in our Consolidated Balance Sheets. Operating results pertaining to these properties were reclassified to discontinued operations for all prior periods presented in our Consolidated Statements of Comprehensive Income. The following table illustrates the number of sold or held-for-sale properties included in, or excluded from, discontinued operations in this report: Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Total Properties included in discontinued operations 10 37 2 49 Properties included in continuing operations 1 2 8 11 Properties sold or classified as held for sale 11 39 10 60 The following table illustrates the number of sold or held-for-sale properties included in discontinued operations by reportable segment: Reportable Segment Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Florida 3 — — Houston — — 1 Southeastern PA 5 32 1 Other 2 5 — Total 10 37 2 A summary of the results of operations for the properties classified as discontinued operations through the respective disposition dates is as follows (in thousands): For the Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Revenue Rental $ 43,393 $ 61,405 $ 48,343 Operating expense reimbursement 12,663 27,024 23,042 Total Revenue 56,056 88,429 71,385 Expenses Rental property 6,959 17,826 13,783 Real estate taxes 7,354 11,582 6,873 Other operating expense (9 ) (272 ) 110 Interest expense 5,812 6,858 9,950 Depreciation and amortization 5,356 19,190 13,642 Impairment charges - real estate assets 7,257 6,686 — Total Expense 32,729 61,870 44,358 Interest and other income 52 102 104 Gain on property dispositions 303,159 14,578 — Income taxes — — (2 ) Income from discontinued operations 326,538 41,239 27,129 Noncontrolling interest - operating partnership (7,608 ) (965 ) (632 ) Income available to common shareholders $ 318,930 $ 40,274 $ 26,497 Interest expense has been allocated to discontinued operations. The allocation of interest expense to discontinued operations was based on the ratio of net assets sold and held for sale (without continuing involvement) to the sum of total net assets plus consolidated debt. Capital expenditures on a cash basis for the year ended December 31, 2018, 2017 and 2016 were $6.1 million , $62.4 million and $18.9 million , respectively, related to properties within discontinued operations. In October 2016, the Company completed the sale of a portfolio of 108 properties totaling approximately 7.6 million square feet and 26.7 acres of land for $969 million for a net gain of $179.1 million . As this sale did not represent a strategic shift for the Company, it is not classified as discontinued operations. A summary of net income (excluding gain on sale) related to this portfolio is as follows (in thousands): Year Ended December 31, 2016 Net income $ 48,609 Noncontrolling interest - operating partnership (1,142 ) Income available to common shareholders $ 47,467 Assets Held for Sale As of December 31, 2018, 11 operating properties and 69 acres of land held for development were classified as held for sale, of which 10 operating properties met the criteria to be classified within discontinued operations. As of December 31, 2017, 27 operating properties were classified as held for sale, of which 25 operating properties met the criteria to be classified within discontinued operations. In addition as of December 31, 2017, nine acres of land held for development were classified as held for sale and classified within continuing operations. The following table illustrates aggregate balance sheet information for all held-for-sale properties (in thousands): December 31, 2018 December 31, 2017 Included in Continuing Operations Included in Discontinued Operations Total Included in Continuing Operations Included in Discontinued Operations Total Land and land improvements $ 1,301 $ 92,889 $ 94,190 $ 3,476 $ 155,974 $ 159,450 Buildings and improvements 5,638 126,001 131,639 80,738 493,615 574,353 Development in progress — — — — 45,035 45,035 Land held for development 26,253 — 26,253 863 — 863 Accumulated depreciation (1,546 ) (36,569 ) (38,115 ) (11,785 ) (187,335 ) (199,120 ) Deferred financing and leasing costs, net 58 2,781 2,839 2,210 15,296 17,506 Other assets 164 3,575 3,739 5,137 19,351 24,488 Assets held for sale $ 31,868 $ 188,677 $ 220,545 $ 80,639 $ 541,936 $ 622,575 Liabilities held for sale $ 141 $ 3,042 $ 3,183 $ 1,153 $ 13,470 $ 14,623 In January 2019, three properties totaling 151,000 square feet which were held for sale and classified in discontinued operation in the Company's Florida segment as of December 31, 2018 were sold for $23.4 million . Asset Impairment The Company evaluates its real estate investments upon the occurrence of significant adverse changes in operations to assess whether any impairment indicators are present that could affect the recovery of the recorded value. In addition to other factors it considers as described in Note 2 - Summary of Significant Accounting Policies, the Company considers strategic divestiture decisions that have either resulted in the disposition or potential disposition of certain properties prior to the end of their remaining useful lives. As a result, during the years ended December 31, 2018 , 2017 and 2016 , the Company recognized impairment losses of $39.7 million , $10.6 million and $3.9 million , respectively. The impairment losses are for operating properties or land parcels and were in the reportable segments and for the amounts as indicated below (in thousands): Year Ended December 31, Reportable Segment 2018 2017 2016 Florida $ 2,396 $ — $ — Houston — 10,632 — Chicago/Minneapolis 2,456 — 3,879 Philadelphia 26,000 — — Southeastern PA 1,579 — — Other 7,257 — — Total $ 39,688 $ 10,632 $ 3,879 Consistent with its strategy to divest its remaining office properties and focus its efforts and capital solely on its industrial platform, the Company evaluated its office properties and land holdings in the latter part of 2018, and as a result, recognized impairment losses on certain properties which the Company is either holding for sale and/or it is planning to sell. For the year ended December 31, 2018, the Company recorded an impairment charge of $7.3 million relating to one office property held for sale which is included in discontinued operations, and impairments of $6.4 million relating to certain land holdings, which is included in impairment - real estate assets in the Company's consolidated statements of comprehensive income. In addition, the Company recorded an impairment of $26.0 million related to its Camden Waterfront project located in Camden, New Jersey which is included in impairment - real estate assets in the Company's consolidated statements of comprehensive income. The Company evaluated the recoverability of the carrying value of its total investment in the Camden Waterfront project in 2018. Factors considered in evaluating the carrying value of this project included probability weighted projections of future cash flows, which are influenced by management’s judgments regarding the site configuration, absorption rates and timing of future fee development projects, the amount, timing and sunset provisions of government incentives aimed at inducing office users to relocate to Camden, and general market conditions affecting demand for office space in Camden. As a result of changes to management’s estimates of probability weighted future cash flow impacted by the above-described factors during the second quarter of 2018, the Company concluded that an indicator of impairment existed and the Company may not recover the carrying value of its investment in the Camden Waterfront project. As such, the Company recorded the impairment charge in the second quarter of 2018. The impairment charge was equal to the amount by which the Company estimated the carrying value of its total investment in the Camden Waterfront project exceeded the current estimated fair value of its investment. For the year ended December 31, 2017, $6.7 million in impairments related to properties sold were included in discontinued operations and $3.9 million in impairment - real estate assets related to land held for development. Consistent with the Company’s strategy to divest suburban office properties in 2017, as discussed above, properties and related land were disposed of before the end of their estimated useful lives at a time when the market price was below the Company’s net investment in the properties. For the year ended December 31, 2016, $3.9 million in impairments related to properties sold. The Company determined the above-described impairments based on third party offer prices and quoted offer prices for comparable transactions which are Level 2 and Level 3 inputs, respectively, according to the fair value hierarchy established in ASC 820. These measurements have occurred throughout the respective periods as circumstances arise, and the resulting estimates of fair value are not necessarily reflective of measurements at the period’s end. The Company has evaluated each of its properties and land held for development and has determined that there were no additional valuation adjustments necessary at December 31, 2018 . The Company applied reasonable estimates and judgments in determining the level of impairments recognized. Should external or internal circumstances change requiring the need to shorten the holding periods or adjust the estimated future cash flows of the Company’s assets, the Company could be required to record impairment charges in the future.

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	DERIVATIVE INSTRUMENTS The Company borrows funds at a combination of fixed and variable rates. Borrowings under the Company's Facilities and certain bank mortgage loans bear interest at variable rates. Our long-term debt typically bears interest at fixed rates. The Company's interest rate risk management objectives are to limit generally the impact of interest rate changes on earnings and cash flows and to lower the Company's overall borrowing costs. To achieve these objectives, from time to time, the Company enters into interest rate hedge contracts such as collars, swaps, caps and treasury lock agreements in order to mitigate our interest rate risk with respect to various debt instruments. The Company generally does not hold or issue these derivative contracts for trading or speculative purposes. The interest rate on all of the Company's variable rate debt is generally adjusted at, daily, one or three month intervals, subject to settlements under interest rate hedge contracts. Cash Flow Hedges of Interest Rate Risk Interest rate swaps involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive loss (for the Trust) and general partner's equity and limited partners' equity - common units (for the Operating Partnership) and is subsequently reclassified into interest expense in the period that the hedged forecasted transaction affects earnings. The Company determines the fair value of its interest rate derivatives by using the standard methodology of netting discounted future fixed cash payments with the discounted expected variable cash receipts. These variable cash receipts of interest rate derivatives are based on expectations of future interest rates (forward curves) estimated by observing market interest rate curves. This is a Level 2 fair value calculation. Also, credit valuation adjustments are factored into the fair value calculations to account for potential nonperformance risk. These credit valuation adjustments were concluded to be not significant inputs for the fair value calculations for the periods presented. During 2017 and a portion of 2018, the Company held an interest in three interest rate swap contracts (“Swaps”) that eliminate the impact of changes in interest rates on the payments required under variable rate mortgages that were also assumed. The Swaps had aggregate notional amounts of $66.8 million and $96.2 million at December 31, 2018 and 2017 , respectively, and two of the Swaps expire in 2020 . One interest rate swap contract and related mortgage loan were repaid in April 2018 on the maturity date. In 2018, in anticipation of conducting an offering of senior notes, the Operating Partnership entered into two interest rate lock agreements tied to the U.S. treasury rate for an aggregate notional amount of $200 million . An interest rate lock is a tool used to manage interest-rate risk by effectively securing interest rates on federal government securities as of the agreement date, to cover future expenses that will be financed by a debt offering. One agreement had a notional amount of $100 million and expired in 2018 and was settled for $2.4 million . The second agreement had a notional amount of $100 million and expired in 2019. It was settled prior to consummation of the January 2019 offering of senior notes for $3.3 million . See Note 21 - Subsequent Events. The Company accounts for the effective portion of changes in the fair value of a derivative in accumulated other comprehensive loss and subsequently reclassifies the effective portion to earnings over the term that the hedged transaction affects earnings. The Company accounts for the ineffective portion of changes in the fair value of a derivative directly in earnings. The following table presents the location in the financial statements of the gains or losses recognized related to the Company’s cash flow hedges for the year ended December 31, 2018 , 2017, and 2016 (in thousands): Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Amount of gain (loss) related to the effective portion recognized in other comprehensive income (loss) $ (3,477 ) $ 176 $ (648 ) Amount of gain (loss) related to the effective portion reclassified to interest expense $ 228 $ (453 ) $ (1,069 ) Amount of gain (loss) related to the ineffective portion recognized in interest expense $ 91 $ 168 $ (48 ) The following table presents the fair value of the Company’s derivative financial instruments as well as their classification on the accompanying consolidated balance sheets as of December 31, 2018 and December 31, 2017 (amounts in thousands). Derivatives Fair Value at: Balance Sheet Location December 31, 2018 December 31, 2017 Derivatives designated as hedging instruments: Interest Rate Swaps Other Liabilities $ 677 $ 2,243 Interest Rate Treasury Locks Other Liabilities 3,972 — Total $ 4,649 $ 2,243 Amounts reported in accumulated other comprehensive income related to derivatives will be reclassified to interest expense as interest payments are made on the Company’s variable-rate debt. The Company estimates that $8,000 will be reclassified from accumulated other comprehensive loss as a decrease to interest expense over the next twelve months. The Company has agreements with its derivative counterparties that contain a provision whereby if the Company defaults on any of its indebtedness, including defaults where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations. If the Company were to breach any of the contractual provisions of the derivative contracts, it would be required to settle its obligations under the agreements at their termination value including accrued interest for approximately $4.7 million .

Supplemental Disclosure to Cons

Supplemental Disclosure to Consolidated Statement of Cash Flows	12 Months Ended
	Dec. 31, 2018
Supplemental Disclosure to Statements of Cash Flows [Abstract]
Supplemental Disclosure to Consolidated Statement of Cash Flows	SUPPLEMENTAL DISCLOSURE TO CONSOLIDATED STATEMENT OF CASH FLOWS The following are supplemental disclosures to the statements of cash flows for the years ended December 31, 2018 , 2017 and 2016 (amounts in thousands): 2018 2017 2016 Write-off of fully depreciated/amortized property and deferred costs - properties included in continuing operations $ 50,169 $ 24,985 $ 34,399 Write-off of fully depreciated/amortized property and deferred costs - properties included in discontinued operations 247 6,951 7,007 Write-off of depreciated property and deferred costs due to sale/demolition - properties included in continuing operations 20,272 15,760 461,480 Write-off of depreciated property and deferred costs due to sale/demolition - properties included in discontinued operations 143,572 17,335 — Write-off of costs related to early debt extinguishment — — 219 Changes in accrued development capital expenditures - properties included in continuing operations 9,078 14,723 (13,651 ) Changes in accrued development capital expenditures - properties included in discontinued operations (1,880 ) (2,382 ) 2,283 Unrealized (loss) gain on cash flow hedge (3,700 ) 605 410 Capitalized equity-based compensation 972 1,096 1,221 Redemption of noncontrolling interests - common units — 152 132 Amounts paid in cash for deferred leasing costs incurred in connection with signed leases with tenants are paid in conjunction with improving (acquiring) property, plant and equipment. Such costs are not contained within net real estate. However, they are integral to the completion of a tenant lease and ultimately are related to the improvement and thus the value of the Company’s property, plant and equipment. They are therefore included in investing activities in the Company’s consolidated statements of cash flows. The following is a reconciliation of the Company's cash and cash equivalents and restricted cash at the beginning and end of the years ended December 31, 2018 and 2017 (amounts in thousands): 2018 2017 Cash and cash equivalents at beginning of period $ 11,882 $ 43,642 Restricted cash at beginning of period 13,803 12,383 Cash and cash equivalents and restricted cash at beginning of period $ 25,685 $ 56,025 Cash and cash equivalents at end of period $ 84,923 $ 11,882 Restricted cash at end of period 10,899 13,803 Cash and cash equivalents and restricted cash at end of period $ 95,822 $ 25,685 Restricted cash includes tenant security deposits and escrow funds that the Company maintains pursuant to certain mortgage loans. Restricted cash also includes the undistributed proceeds from the sale of land in Kent County, United Kingdom.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS In January 2019, the Company issued $350 million of 4.375% senior unsecured notes due 2029. The Company used the proceeds to pay down its revolving credit facilities. In October and November 2018, in anticipation of conducting an offering of senior notes, the Operating Partnership entered into two interest rate lock agreements tied to the U.S. treasury rate. These agreements were settled prior to the consummation of the described above senior note offering for an aggregate cost to the Operating Partnership of $5.7 million . See Note 20 - Derivative Instruments.

Schedule II

Schedule II	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule of Valuation and Qualifying Accounts Disclosure	Liberty Property Trust and Liberty Property Limited Partnership Schedule II (in thousands) The following table details the activity for the allowance for doubtful accounts. Balance at December 31, 2017 Additions Deductions Balance at December 31, 2018 Allowance for Doubtful Accounts - Straight Line Rent $ 549 $ 1,431 $ (647 ) $ 1,333 Allowance for Doubtful Accounts - Accounts Receivable 6,063 5,925 (6,905 ) 5,083 Total $ 6,612 $ 7,356 $ (7,552 ) $ 6,416 Balance at December 31, 2016 Additions Deductions Balance at December 31, 2017 Allowance for Doubtful Accounts - Straight Line Rent $ 530 $ 1,729 $ (1,710 ) $ 549 Allowance for Doubtful Accounts - Accounts Receivable 6,802 7,248 (7,987 ) 6,063 Total $ 7,332 $ 8,977 $ (9,697 ) $ 6,612 Balance at December 31, 2015 Additions Deductions Balance at December 31, 2016 Allowance for Doubtful Accounts - Straight Line Rent $ 581 $ 824 $ (875 ) $ 530 Allowance for Doubtful Accounts - Accounts Receivable 6,317 4,950 (4,465 ) 6,802 Total $ 6,898 $ 5,774 $ (5,340 ) $ 7,332

Schedule III

Schedule III	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation Disclosure [Abstract]
Real Estate and Accumulated Depreciation	LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 1467 Perryman Road Aberdeen, MD $ — $ 12,052,635 $ — $ 35,350,875 $ 12,334,030 $ 35,069,480 $ 47,403,510 $ 4,214,259 2014 5 - 40 1501 Perryman Road Aberdeen, MD — 5,813,324 18,874,059 6,378,428 5,816,839 25,248,972 31,065,811 8,227,740 2005 5 - 40 869 S Route 53 Addison, IL — 1,194,223 4,201,881 230,036 1,194,223 4,431,918 5,626,141 658,252 2013 5 - 40 901 S Route 53 Addison, IL — 2,055,066 5,984,093 879,888 2,055,066 6,863,981 8,919,047 1,230,963 2013 5 - 40 8620 Congdon Hill Drive Alburtis, PA — 38,328,000 — 36,647,068 38,328,000 36,647,068 74,975,068 3,101,872 2015 5 - 40 200 Boulder Drive Allentown, PA — 4,722,683 18,922,645 2,434,125 4,722,683 21,356,770 26,079,453 7,396,339 2004 5 - 40 250 Boulder Drive Allentown, PA — 3,599,936 12,099,145 2,199,097 3,717,733 14,180,445 17,898,178 5,997,398 2004 5 - 40 400 Nestle Way Allentown, PA — 8,065,500 — 31,538,572 8,184,096 31,419,976 39,604,072 16,558,762 1997 5 - 40 650 Boulder Drive Allentown, PA — 5,208,248 — 32,440,853 9,961,788 27,687,313 37,649,101 11,327,870 2002 5 - 40 651 Boulder Drive Allentown, PA — 4,308,646 — 18,551,417 4,308,646 18,551,417 22,860,063 10,468,080 2000 5 - 40 700 Nestle Way Allentown, PA — 3,473,120 — 20,401,484 4,174,970 19,699,634 23,874,604 11,536,583 1998 5 - 40 705 Boulder Drive Allentown, PA — 10,594,027 — 28,810,136 10,596,767 28,807,396 39,404,163 17,664,832 2001 5 - 40 7165 Ambassador Drive Allentown, PA — 792,999 — 4,694,609 804,848 4,682,760 5,487,608 2,265,255 2002 5 - 40 7248 Industrial Boulevard Allentown, PA — 2,670,849 13,307,408 4,665,457 2,670,673 17,973,041 20,643,714 9,990,484 1988 5 - 40 7339 Industrial Boulevard Allentown, PA — 1,187,776 — 7,592,257 1,197,447 7,582,586 8,780,033 4,441,217 1996 5 - 40 7437 Industrial Boulevard Allentown, PA — 717,488 5,022,413 4,003,719 726,651 9,016,968 9,743,619 5,686,680 1976 5 - 40 8014 Industrial Boulevard Allentown, PA — 4,019,258 — 12,646,983 3,645,117 13,021,124 16,666,241 5,718,258 1999 5 - 40 8150 Industrial Boulevard Allentown, PA — 2,564,167 — 9,443,051 2,571,466 9,435,752 12,007,218 4,279,822 2002 5 - 40 8250 Industrial Boulevard Allentown, PA — 1,025,667 — 5,254,712 1,035,854 5,244,525 6,280,379 2,154,620 2002 5 - 40 8400 Industrial Boulevard Allentown, PA — 6,725,948 — 27,402,563 7,521,211 26,607,300 34,128,511 8,740,124 2005 5 - 40 6330 Hedgewood Drive Allentown, PA — 531,268 — 6,029,991 532,047 6,029,212 6,561,259 4,218,156 1988 5 - 40 6350 Hedgewood Drive Allentown, PA — 360,027 — 4,526,060 560,691 4,325,396 4,886,087 2,757,186 1989 5 - 40 6370 Hedgewood Drive Allentown, PA — 540,795 — 4,369,686 541,459 4,369,022 4,910,481 2,735,162 1990 5 - 40 6390 Hedgewood Drive Allentown, PA — 707,203 — 3,446,028 707,867 3,445,364 4,153,231 2,054,135 1990 5 - 40 6520 Stonegate Drive Allentown, PA — 453,315 — 1,589,269 484,361 1,558,223 2,042,584 770,493 1996 5 - 40 6540 Stonegate Drive Allentown, PA — 422,042 — 5,337,127 422,730 5,336,439 5,759,169 3,335,623 1988 5 - 40 6560 Stonegate Drive Allentown, PA — 458,281 — 3,856,517 458,945 3,855,853 4,314,798 2,468,547 1989 5 - 40 6580 Snowdrift Road Allentown, PA — 388,328 — 4,876,767 389,081 4,876,014 5,265,095 3,417,222 1988 5 - 40 7620 Cetronia Road Allentown, PA — 1,091,806 3,851,456 780,423 1,093,724 4,629,961 5,723,685 2,503,775 1990 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 2250 East Bardin Road Arlington, TX 4,754,659 — 1,110,192 5,864,850 30,284,926 36,149,776 434,113 2017 5 - 40 3095 Presidential Drive Atlanta, GA — 200,351 1,729,161 255,502 200,351 1,984,663 2,185,014 436,384 2013 5 - 40 3097 Presidential Drive Atlanta, GA — 188,680 1,721,048 405,231 188,680 2,126,279 2,314,959 359,030 2013 5 - 40 7030 Buford Highway NE Atlanta, GA — * 919,850 4,051,340 954,682 919,850 5,006,022 5,925,872 1,064,051 2013 5 - 40 Barton 150, Lichfield Road, Barton Business Park Barton Under Needwood, UK * 2,196,955 13,643,981 (3,633,742 ) 1,692,997 10,514,197 12,207,194 1,647,568 2018 5 - 40 1055-1071 Kingsland Drive Batavia, IL — 727,294 2,367,529 706,473 727,294 3,074,002 3,801,296 659,693 2013 5 - 40 4606 Richlynn Drive Belcamp, MD — 299,600 1,818,861 722,788 299,600 2,541,649 2,841,249 1,231,732 1985 5 - 40 11800 Baltimore Avenue Beltsville,MD — 2,769,962 1,829,028 267,937 2,663,725 2,203,203 4,866,928 430,470 2013 5 - 40 11850 Baltimore Avenue Beltsville,MD — 3,595,044 2,415,132 164,477 3,457,162 2,717,491 6,174,653 759,246 2013 5 - 40 11900 Baltimore Avenue Beltsville,MD — 3,492,036 2,024,038 520,179 3,358,104 2,678,149 6,036,253 851,104 2013 5 - 40 12104 Indian Creek Court Beltsville,MD — 2,021,752 2,503,802 339,825 2,021,752 2,843,627 4,865,379 765,205 2013 5 - 40 12200 Indian Creek Court Beltsville,MD — 1,347,882 1,460,291 623,867 1,347,882 2,084,158 3,432,040 479,038 2013 5 - 40 12240 Indian Creek Court Beltsville,MD — 1,479,307 2,159,997 791,665 1,479,307 2,951,663 4,430,970 635,369 2013 5 - 40 1071 Thorndale Avenue Bensenville,IL — 2,173,006 2,280,788 291,248 2,016,715 2,728,327 4,745,042 605,234 2013 5 - 40 1260-1274 Ellis Street Bensenville,IL — * 2,298,560 4,020,382 360,126 2,298,560 4,380,508 6,679,068 910,658 2013 5 - 40 371-377 Meyer Road Bensenville,IL — * 1,903,423 3,563,953 581,650 1,903,423 4,145,603 6,049,026 835,950 2013 5 - 40 350 North York Road Bensenville, IL 3,043,130 — (1,288,668 ) 1,754,462 4,763,320 6,517,782 1,668 2017 5 - 40 850-880 Devon Ave Bensenville,IL — * 2,958,756 7,959,013 780,065 2,958,756 8,739,078 11,697,834 1,719,794 2013 5 - 40 10 Emery Street Bethlehem, PA — 5,591,216 32,941,818 8,083,706 8,947,574 37,669,166 46,616,740 6,155,898 2014 5 - 40 2785 Commerce Center Boulevard Bethlehem, PA — 11,961,623 — 46,707,077 12,009,985 46,658,715 58,668,700 7,007,059 2011 5 - 40 1455 Remington Boulevard Bolingbrook, IL — 2,501,294 10,704,719 26,008 2,501,294 10,730,727 13,232,021 1,725,320 2012 5 - 40 150 E Crossroads Parkway Bolingbrook, IL — * 3,078,949 14,143,377 1,303,328 3,078,949 15,446,705 18,525,654 2,859,514 2013 5 - 40 553 S Joliet Ave Bolingbrook, IL — * 3,764,831 15,109,947 2,933,005 3,764,831 18,042,952 21,807,783 3,595,146 2013 5 - 40 400 Boulder Drive Breinigsville, PA — 2,859,106 — 12,772,102 2,865,575 12,765,633 15,631,208 4,196,273 2003 5 - 40 8201 Industrial Boulevard Breinigsville, PA — 2,089,719 — 9,261,318 2,222,168 9,128,869 11,351,037 2,428,891 2006 5 - 40 8451 Willard Drive Breinigsville, PA — 8,752,708 — 40,889,400 11,511,499 38,130,609 49,642,108 12,471,964 2007 5 - 40 860 Nestle Way Breinigsville, PA — 8,118,881 18,885,486 7,522,275 8,118,881 26,407,761 34,526,642 11,645,718 2004 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 3525 Gravel Springs Road Buford, GA — 1,391,065 — 5,767,103 1,629,677 5,528,491 7,158,168 219,606 2015 5 - 40 3535 Gravel Springs Road Buford, GA — 2,807,020 — 9,458,307 3,077,350 9,187,977 12,265,327 333,446 2015 5 - 40 Tesco Trunking Station Caldicott, UK — * 5,755,835 20,336,288 29,673,532 5,755,835 23,917,697 29,673,532 200,687 2018 5 - 40 100 Carolina Way Carlisle, PA — 10,830,187 32,143,152 10,830,187 32,143,152 42,973,339 538,847 2017 5 - 40 1485 Dennison Circle Carlisle, PA — 4,249,868 13,886,039 2,344,063 4,095,262 16,384,708 20,479,970 7,258,566 2004 5 - 40 40 Logistics Drive Carlisle, PA — 7,981,850 — 33,016,988 8,081,272 32,917,566 40,998,838 6,179,664 2011 5 - 40 105 Amor Avenue Carlstadt, NJ — — — 7,529,232 5,229,867 2,299,365 7,529,232 30,122 2018 5 - 40 135-195 East Elk Trail Carol Stream, IL — 4,873,094 12,430,320 2,711,630 4,873,094 15,141,950 20,015,044 2,164,779 2013 5 - 40 515 Kehoe Boulevard Carol Stream, IL — 5,523,427 14,581,705 1,016,882 5,523,427 15,598,587 21,122,014 2,222,829 2013 5 - 40 1413 Bradley Lane Carrollton, TX — * 247,477 2,028,322 233,527 247,477 2,261,849 2,509,326 255,915 2013 5 - 40 3200 Belmeade Drive Carrollton, TX — 1,042,453 8,027,974 595,707 1,042,453 8,623,681 9,666,134 1,493,508 2013 5 - 40 16325 S Avalon Blvd Carson, CA — 26,432,369 19,669,675 387,002 26,476,167 20,012,879 46,489,046 669,481 2017 5 - 40 1475 Nitterhouse Dr Chambersburg, PA — 7,081,007 39,002,011 2,091,556 7,081,007 41,093,567 48,174,574 7,376,996 2013 5 - 40 95 Kriner Road Chambersburg, PA — 8,695,501 — 35,058,041 9,407,871 34,345,671 43,753,542 10,389,249 2006 5 - 40 9000 109th Street Champlin, MN — 1,251,043 11,662,995 119,919 1,251,043 11,782,914 13,033,957 2,461,549 2011 5 - 40 11701 Goodrich Drive Charlotte, NC — 2,054,621 6,356,151 1,022,332 2,054,621 7,378,482 9,433,103 1,633,427 2013 5 - 40 12810 Virkler Drive Charlotte, NC — 475,368 2,367,586 921,907 476,262 3,288,598 3,764,860 662,261 2010 5 - 40 2700 Hutchison McDonald Road Charlotte, NC — 912,500 4,721,259 366,811 912,500 5,088,070 6,000,570 1,049,544 2011 5 - 40 2701 Hutchison McDonald Road Charlotte, NC — 1,275,000 4,649,750 684,784 1,275,000 5,334,534 6,609,534 1,115,197 2011 5 - 40 2730 Hutchison McDonald Road Charlotte, NC — 1,878,750 10,129,499 170,089 1,878,750 10,299,588 12,178,338 1,967,588 2011 5 - 40 2801 Hutchison McDonald Road Charlotte, NC — 1,065,000 6,975,250 813,680 1,065,000 7,788,930 8,853,930 1,490,060 2011 5 - 40 3000 Crosspoint Center Lane Charlotte, NC — 1,831,250 10,779,412 1,146,648 1,831,250 11,926,060 13,757,310 2,435,771 2011 5 - 40 3005 Crosspoint Center Lane Charlotte, NC — 1,990,000 6,561,540 1,169,186 1,990,000 7,730,726 9,720,726 1,619,220 2011 5 - 40 4045 Perimeter West Drive Charlotte, NC — 1,418,928 7,511,050 631,990 1,418,928 8,143,040 9,561,968 1,703,407 2011 5 - 40 4047 Perimeter West Drive Charlotte, NC — 1,279,004 — 6,399,096 1,279,004 6,399,096 7,678,100 1,281,462 2011 5 - 40 4525 Statesville Road Charlotte, NC — 841,250 5,279,315 667,246 837,144 5,950,667 6,787,811 1,047,780 2011 5 - 40 4835 Sirona Drive Charlotte, NC 3,194,355 690,750 5,086,388 94,118 690,750 5,180,506 5,871,256 865,138 2012 5 - 40 4925 Sirona Drive Charlotte, NC 3,227,439 603,003 4,969,011 152,435 603,003 5,121,446 5,724,449 968,523 2012 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 5032 Sirona Drive Charlotte, NC — 1,416,763 — 9,030,334 1,416,763 9,030,334 10,447,097 776,614 2015 5 - 40 5033 Sirona Drive Charlotte, NC 2,753,026 509,247 4,710,218 165,463 613,962 4,770,966 5,384,928 831,612 2012 5 - 40 5039 Sirona Drive Charlotte, NC — 1,027,500 6,172,807 62,651 1,027,500 6,235,458 7,262,958 670,560 2014 5 - 40 8910 Pioneer Avenue Charlotte, NC — 527,873 4,959,206 360,419 527,873 5,319,625 5,847,498 983,509 2011 5 - 40 8916 Pioneer Avenue Charlotte, NC — 557,730 5,785,333 555,839 557,730 6,341,172 6,898,902 1,372,889 2011 5 - 40 8924 Pioneer Avenue Charlotte, NC — 654,713 5,365,823 (55,823 ) 654,713 5,310,000 5,964,713 269,234 2016 5 - 40 3923 Shutterfly Road Charlotte, NC — — — 9,967,121 895,209 9,071,912 9,967,121 70,798 2018 5 - 40 3929 Shutterfly Road Charlotte, NC — 592,233 — 581,457 1,173,690 10,559,454 11,733,144 217,685 2016 5 - 40 2601 Indian River Road Chesapeake, VA — * 1,711,746 10,418,032 493,191 1,711,746 10,911,223 12,622,969 1,970,775 2013 5 - 40 1540 S 54th Avenue Cicero, IL — 3,540,236 20,130,552 928,916 3,540,236 21,059,468 24,599,704 3,668,514 2013 5 - 40 4650 Lake Forest Drive Cincinnati, OH — 1,030,242 4,003,024 388,666 1,030,242 4,391,689 5,421,931 870,081 2013 5 - 40 4750 Lake Forest Drive Cincinnati, OH — 1,138,166 5,914,789 240,972 1,138,166 6,155,761 7,293,927 1,122,251 2013 5 - 40 15025 Proctor Ave City of Industry, CA — — — 27,991,514 16,149,929 11,841,585 27,991,514 26,802 2018 5 - 40 9645 Gerwig Lane Columbia, MD — 1,915,960 6,461,228 507,087 1,915,960 6,968,315 8,884,275 1,143,213 2013 5 - 40 2550 John Glenn Avenue Columbus, OH — 540,601 5,129,342 1,072,491 540,601 6,201,833 6,742,434 1,046,557 2013 5 - 40 3800 Twin Creeks Drive Columbus, OH — 549,393 4,643,302 481,884 549,393 5,125,186 5,674,579 891,452 2013 5 - 40 5959 Randolph St Commerce, CA — — — 88,344,713 34,612,210 53,732,503 88,344,713 1,313,050 2018 5 - 40 330 South Royal Lane Coppell, TX — 2,091,426 — 11,402,502 2,091,426 11,402,502 13,493,928 1,288,604 2014 5 - 40 455 Airline Drive Coppell, TX — * 312,701 2,311,531 489,677 312,701 2,801,208 3,113,909 606,996 2013 5 - 40 2130 Baldwin Avenue Crofton, MD — 3,172,032 7,350,782 418,907 3,172,032 7,769,689 10,941,721 1,450,318 2013 5 - 40 11020 Holly Lane Dayton, MN — 2,536,731 — 12,279,946 2,536,731 12,279,946 14,816,677 786,823 2016 5 - 40 329-333 Herrod Blvd Dayton, NJ — * 4,039,559 20,863,051 2,285,014 4,039,559 23,148,065 27,187,624 4,102,628 2013 5 - 40 1250 Hall Court Deer Park, TX — 829,570 4,778,327 171,544 831,611 4,947,830 5,779,441 1,575,091 2006 5 - 40 333 Howard Avenue Des Plaines, IL — 7,928,724 — 14,263,106 7,928,724 14,263,106 22,191,830 1,330,094 2016 5 - 40 131 Aldersgate Street & 14 -17 Carthusian Street Douglas, UK — 3,594,064 1,301,980 — 3,594,064 1,301,980 4,896,044 8,199 2018 5 - 40 1680 Executive Drive Duluth, GA — 1,928,412 4,651,819 1,154,075 1,928,412 5,805,894 7,734,306 1,268,370 2013 5 - 40 1700 Executive Drive Duluth, GA — 1,082,072 2,496,599 625,991 1,082,072 3,122,590 4,204,662 776,229 2013 5 - 40 2670 Breckinridge Blvd Duluth, GA — 1,676,415 4,567,592 980,381 1,676,415 5,547,974 7,224,389 1,104,805 2013 5 - 40 170 Parkway West Duncan, SC — 598,348 3,643,756 1,228,006 598,918 4,871,192 5,470,110 1,448,618 2006 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 190 Parkway West Duncan, SC — 551,663 3,310,993 251,300 552,211 3,561,744 4,113,955 1,166,823 2006 5 - 40 265 Parkway East Duncan, SC — 901,444 5,751,389 193,199 902,374 5,943,658 6,846,032 2,239,383 2006 5 - 40 285 Parkway East Duncan, SC — 975,433 5,851,990 1,173,262 976,393 7,024,292 8,000,685 2,105,505 2006 5 - 40 1000 Parliament Court Durham, NC — 2,229,000 7,064,506 985,898 2,229,000 8,050,404 10,279,404 978,653 2014 5 - 40 4226 Surles Court Durham, NC — 1,440,000 7,932,265 306,380 1,440,000 8,238,645 9,678,645 1,247,620 2014 5 - 40 4227 Surles Court Durham, NC — 1,500,000 5,624,030 234,711 1,500,000 5,858,740 7,358,740 692,281 2014 5 - 40 4234 Surles Court Durham, NC — 1,440,000 7,356,161 (11,072 ) 1,440,000 7,345,089 8,785,089 982,836 2014 5 - 40 4300 Emperor Center Durham, NC — 1,576,500 4,240,961 189,629 1,576,500 4,430,590 6,007,090 549,462 2014 5 - 40 1951 TW Alexander Drive Durham, NC — 1,115,595 — 3,644,168 1,324,734 3,435,029 4,759,763 188,268 2015 5 - 40 1953 TW Alexander Drive Durham, NC — 2,402,820 — 6,586,494 2,853,273 6,136,041 8,989,314 291,107 2015 5 - 40 1955 TW Alexander Drive Durham, NC — 758,503 — 9,120,096 2,453,348 7,425,251 9,878,599 71,932 2017 5 - 40 1957 TW Alexander Drive Durham, NC — 1,844,943 — 7,950,175 3,091,046 6,704,072 9,795,118 411,361 2015 5 - 40 3169 Dodd Road Eagan, MN — 988,594 6,586,907 225,918 988,594 6,812,825 7,801,419 1,184,526 2012 5 - 40 3711 Kennebec Drive Eagan, MN — 999,702 4,042,589 (934 ) 999,702 4,041,655 5,041,357 866,480 2011 5 - 40 917 Lone Oak Road Eagan, MN — * 1,493,115 6,120,455 986,900 1,493,115 7,107,355 8,600,470 1,453,058 2013 5 - 40 10301-10305 West 70th Street Eden Prairie, MN — 120,622 1,085,226 297,669 105,657 1,397,860 1,503,517 756,571 1984 5 - 40 10321 West 70th Street Eden Prairie, MN — 145,198 1,305,700 601,349 127,181 1,925,066 2,052,247 1,047,920 1984 5 - 40 10333 West 70th Street Eden Prairie, MN — 110,746 995,868 330,889 97,003 1,340,500 1,437,503 702,253 1984 5 - 40 10349-10357 West 70th Street Eden Prairie, MN — 275,903 2,481,666 945,812 241,667 3,461,714 3,703,381 1,957,160 1985 5 - 40 10365-10375 West 70th Street Eden Prairie, MN — 291,077 2,618,194 1,575,676 255,683 4,229,264 4,484,947 2,057,137 1985 5 - 40 10393-10394 West 70th Street Eden Prairie, MN — 269,618 2,423,318 2,574,661 236,903 5,030,694 5,267,597 2,510,427 1985 5 - 40 7075 Flying Cloud Drive Eden Prairie, MN — 10,232,831 10,855,851 4,182,406 10,093,396 15,177,691 25,271,087 4,202,224 2007 5 - 40 7078 Shady Oak Road Eden Prairie, MN — 343,093 3,085,795 1,624,490 336,481 4,716,897 5,053,378 2,838,868 1985 5 - 40 1075 King George Post Road Edison, NJ — — — — — 14,468,904 14,468,904 319,235 2016 5 - 40 1 Truman Drive South Edison, NJ — 27,862,573 19,426,947 1,000,379 27,909,534 20,380,365 48,289,899 655,915 2017 5 - 40 2250 Arthur Avenue Elk Grove, IL — 1,403,196 2,386,396 149,086 1,403,196 2,535,482 3,938,678 477,737 2013 5 - 40 6600 Business Parkway Elkridge, MD — 3,680,220 14,671,910 701,811 3,680,220 15,373,721 19,053,941 2,426,083 2013 5 - 40 6675 Business Parkway Elkridge, MD — * 2,421,854 9,730,192 1,062,508 2,421,854 10,792,700 13,214,554 1,723,311 2013 5 - 40 7351 Coca Cola Drive Elkridge, MD — 1,897,044 — 7,438,573 3,023,417 6,312,200 9,335,617 2,162,388 2006 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 21705-21707 Mississippi Street Elwood, IL — 10,594,259 30,329,802 1,560,421 10,594,259 31,890,224 42,484,483 6,130,681 2011 5 - 40 27143 Elwood International Port Road Elwood, IL — 6,022,000 5,612,934 587,424 6,022,000 6,200,358 12,222,358 1,261,705 2011 5 - 40 1800 Donaldson Road Erlanger, KY — — 13,211,604 925,430 — 14,137,034 14,137,034 4,921,421 2011 5 - 40 6880 Fairfield Drive Fairfield, OH — 412,136 3,029,177 146,362 412,136 3,175,539 3,587,675 556,807 2013 5 - 40 7000-7018 Fairfield Business Fairfield, OH — 367,925 2,205,817 177,642 386,928 2,364,456 2,751,384 404,637 2013 5 - 40 10721 Jasmine Street Fontana, CA — 11,427,061 23,784,779 3,332,270 11,427,061 27,117,049 38,544,110 2,642,439 2015 5 - 40 2000 Southpointe Dr Forest Park, GA — 756,221 9,115,626 619,869 756,221 9,735,495 10,491,716 1,726,418 2013 5 - 40 1400 NW 65th Place Fort Lauderdale, FL — 545,480 2,540,210 85,911 545,480 2,626,121 3,171,601 417,925 2013 5 - 40 6500 NW 12th Avenue Fort Lauderdale, FL — — 3,064,734 477,057 — 3,541,791 3,541,791 694,531 2013 5 - 40 6501 NW 12th Avenue Fort Lauderdale, FL — 519,984 2,677,465 312,769 519,984 2,990,234 3,510,218 461,790 2013 5 - 40 6600 NW 12th Avenue Fort Lauderdale, FL — — 2,988,181 377,561 — 3,365,742 3,365,742 629,720 2013 5 - 40 11222 Melrose Avenue Franklin Park, IL — 2,999,106 4,658,605 103,693 2,999,106 4,762,298 7,761,404 458,865 2016 5 - 40 9601 Cosner Drive Fredericksburg, VA — 475,262 3,917,234 387,586 475,262 4,304,820 4,780,082 2,536,776 1995 5 - 40 5410 - 5430 Northwest 33rd Avenue Ft. Lauderdale, FL — 603,776 4,176,238 2,081,367 625,111 6,236,270 6,861,381 3,556,017 1985 5 - 40 12601 Industry Street Garden Grove, CA — 2,048,143 1,088,697 70,518 2,048,143 1,159,215 3,207,358 326,128 2013 5 - 40 12641 Industry Street Garden Grove, CA — 3,766,822 2,539,214 132,812 3,766,822 2,672,026 6,438,848 496,032 2013 5 - 40 12681-12691 Pala Drive Garden Grove, CA — 5,221,102 3,225,596 91,960 5,220,148 3,318,510 8,538,658 458,102 2014 5 - 40 1720 West 135th Street Gardena, CA — 7,423,389 — 13,111,573 7,427,353 13,107,609 20,534,962 315,243 2017 5 - 40 850 S Jupiter Road Garland, TX — 799,707 6,122,065 525,135 799,707 6,647,200 7,446,907 1,228,448 2013 5 - 40 2510 W Main Street Grand Prairie, TX — * 1,785,741 11,158,818 2,350,115 1,785,741 13,508,933 15,294,674 2,629,047 2013 5 - 40 4251 North Highway 121 Grapevine, TX — * 1,165,780 7,799,270 422,213 1,165,780 8,221,482 9,387,262 1,615,287 2013 5 - 40 1150 Pleasant Ridge Road Greensboro, NC — 1,547,811 — 14,343,114 3,712,683 12,178,242 15,890,925 3,249,276 2006 5 - 40 25 Brookfield Oaks Drive Greenville, SC — 288,823 3,441,512 174,541 288,823 3,616,053 3,904,876 492,665 2014 5 - 40 45 Brookfield Oaks Drive Greenville, SC — 818,114 — 4,789,031 825,529 4,781,616 5,607,145 1,415,767 2006 5 - 40 2011 Southtech Drive Greenwood, IN — 223,702 3,574,142 397,081 223,702 3,971,223 4,194,925 816,565 2013 5 - 40 2121 Southtech Drive Greenwood, IN — 272,823 3,606,920 439,628 272,823 4,046,549 4,319,372 1,042,735 2013 5 - 40 800 Commerce Parkway West Dr Greenwood, IN — 1,374,664 29,963,830 1,822,379 1,374,664 31,786,209 33,160,873 5,435,338 2013 5 - 40 110 Caliber Ridge Dr Greer, SC — 555,549 — 6,559,671 1,241,531 5,873,689 7,115,220 617,188 2014 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 120 Caliber Ridge Dr Greer, SC — 1,243,100 — 6,603,075 1,255,751 6,590,424 7,846,175 775,442 2016 5 - 40 130 Caliber Ridge Dr Greer, SC — 1,171,160 — 6,045,014 1,183,811 6,032,363 7,216,174 516,768 2016 5 - 40 140 Caliber Ridge Drive Greer, SC — 1,243,100 — 6,460,294 1,255,751 6,447,643 7,703,394 794,243 2013 5 - 40 2980 Green Road Greer, SC — 16,338 — 3,732,191 729,479 3,019,050 3,748,529 54,419 2017 5 - 40 2988 Green Road Greer, SC — 2,271,948 — 6,597,878 2,095,033 6,774,793 8,869,826 230,529 2016 5 - 40 125 Caliber Ridge Drive Greer, SC — 464,237 — 5,839,813 1,311,956 4,992,094 6,304,050 1,273,039 2007 5 - 40 2727 London Groveport Road Groveport, OH — 1,875,607 11,937,935 3,165,643 1,875,607 15,103,578 16,979,185 2,654,726 2013 5 - 40 11835 Newgate Boulevard Hagerstown, MD — 14,121,622 — 23,034,177 14,121,622 23,034,177 37,155,799 2,843,048 2014 5 - 40 11841 Newgate Boulevard Hagerstown, MD — 3,356,207 — 30,724,476 9,741,685 24,338,998 34,080,683 7,316,216 2008 5 - 40 1560 Hunter Road Hanover Park, IL — * 2,639,734 12,310,741 1,073,860 2,639,734 13,384,601 16,024,335 2,332,845 2013 5 - 40 1575 Hunter Road Hanover Park, IL — * 3,293,284 17,235,926 1,200,560 3,293,284 18,436,486 21,729,770 3,102,059 2013 5 - 40 7361 Coca Cola Drive Hanover, MD — 2,245,187 — 9,667,649 3,822,710 8,090,126 11,912,836 1,974,018 2004 5 - 40 7460 New Ridge Road Hanover, MD — 3,785,446 — 8,144,397 3,796,023 8,133,820 11,929,843 868,037 2013 5 - 40 7462 New Ridge Road Hanover, MD — 4,059,337 — 7,490,949 4,070,629 7,479,657 11,550,286 699,111 2013 5 - 40 500 McCarthy Drive Harrisburg, PA — 5,194,872 19,991,436 5,018,136 5,687,013 24,517,431 30,204,444 9,708,214 2005 5 - 40 600 Industrial Drive Harrisburg, PA — 7,743,800 — 28,146,140 9,368,557 26,521,383 35,889,940 8,493,295 2005 5 - 40 7195 Grayson Road Harrisburg, PA — 464,534 6,066,272 237,152 464,534 6,303,424 6,767,958 998,330 2013 5 - 40 7253 Grayson Road Harrisburg, PA — 954,130 10,585,367 544,460 954,130 11,129,827 12,083,957 1,792,344 2013 5 - 40 12537 Cerise Avenue Hawthorne, CA — 2,203,194 5,758,809 1,481,588 2,203,194 7,240,397 9,443,591 973,565 2013 5 - 40 1010 Petersburg Road Hebron, KY — 305,471 5,434,505 (819,916 ) 305,471 4,614,589 4,920,060 817,398 2013 5 - 40 785 Lindbergh Court Hebron, KY — 401,410 3,087,899 437,960 401,410 3,525,859 3,927,269 705,925 2013 5 - 40 805 Lindbergh Court Hebron, KY — 292,096 2,502,486 163,618 292,096 2,666,103 2,958,199 547,438 2013 5 - 40 825 Lindbergh Court Hebron, KY — 370,149 3,095,116 442,314 370,149 3,537,431 3,907,580 721,514 2013 5 - 40 845 Lindbergh Court Hebron, KY — 444,318 3,811,889 399,366 444,318 4,211,255 4,655,573 814,352 2013 5 - 40 4198 Eagle Hill Drive High Point, NC — 94,274 — 6,288,127 791,880 5,590,521 6,382,401 1,783,401 2005 5 - 40 4183 Eagle Hill Drive High Point, NC — 122,203 — 3,214,675 526,266 2,810,612 3,336,878 1,406,053 2001 5 - 40 4189 Eagle Hill Drive High Point, NC — 100,106 — 3,582,494 431,106 3,251,494 3,682,600 1,568,325 2001 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 4193 Eagle Hill Drive High Point, NC — 107,586 — 3,522,376 505,700 3,124,262 3,629,962 970,547 2004 5 - 40 4328, 4336 Federal Drive High Point, NC — 521,122 — 5,531,390 825,092 5,227,420 6,052,512 2,697,862 1995 5 - 40 4344 Federal Drive High Point, NC — 484,001 — 3,185,404 173,623 3,495,782 3,669,405 1,967,845 1996 5 - 40 4380 Federal Drive High Point, NC — 282,996 — 2,209,513 283,368 2,209,141 2,492,509 1,273,523 1997 5 - 40 4388 Federal Drive High Point, NC — 143,661 — 1,214,707 132,655 1,225,713 1,358,368 694,546 1997 5 - 40 4475 Premier Drive High Point, NC — 748,693 — 6,918,129 1,525,421 6,141,401 7,666,822 1,581,382 2006 5 - 40 4485 Premier Drive High Point, NC — 1,827,595 — 6,509,786 1,827,595 6,509,786 8,337,381 375,031 2015 5 - 40 4500 Green Point Drive High Point, NC — 230,622 — 2,878,225 231,692 2,877,155 3,108,847 1,721,076 1989 5 - 40 4501 Green Point Drive High Point, NC — 319,289 — 2,941,886 320,450 2,940,725 3,261,175 1,891,827 1989 5 - 40 4523 Green Point Drive High Point, NC — 234,564 — 3,319,067 235,698 3,317,933 3,553,631 2,339,202 1988 5 - 40 4524 Green Point Drive High Point, NC — 182,810 — 2,848,066 183,888 2,846,988 3,030,876 1,912,071 1989 5 - 40 Unit 5 Logix Road Hinckley, UK * 10,547,677 29,691,911 (9,562,316 ) 8,128,152 22,549,120 30,677,272 3,504,963 2018 5 - 40 1000 South Loop West Houston, TX — * 509,351 3,549,504 994,350 509,351 4,543,854 5,053,205 993,896 2013 5 - 40 10241 W Little York Rd Houston, TX — 558,491 5,740,552 138,801 558,491 5,879,353 6,437,844 924,356 2013 5 - 40 10245 W Little York Rd Houston, TX — 426,927 3,460,513 525,045 426,927 3,985,558 4,412,485 934,656 2013 5 - 40 10301 Round Up Lane Houston, TX — 545,501 2,927,700 1,418,126 545,501 4,345,825 4,891,326 723,469 2010 5 - 40 10305 Round Up Lane Houston, TX — 1,340,609 7,489,720 3,263,257 1,340,609 10,752,976 12,093,585 2,762,324 2010 5 - 40 1050 Greens Parkway Houston, TX — 973,482 — 3,531,502 992,093 3,512,891 4,504,984 375,462 2013 5 - 40 10607 Haddington Drive Houston, TX — * 201,469 1,631,561 160,347 201,469 1,791,909 1,993,378 345,323 2013 5 - 40 10735 West Little York Road Houston, TX — 1,110,988 6,351,946 3,158,530 1,135,483 9,485,981 10,621,464 3,706,395 2000 5 - 40 10739 West Little York Road Houston, TX — 797,931 5,950,894 476,655 799,560 6,425,920 7,225,480 2,606,566 1999 5 - 40 11201 Greens Crossing Boulevard Houston, TX — 1,006,194 5,412,584 2,619,384 1,008,542 8,029,620 9,038,162 2,712,516 2007 5 - 40 11220 Ella Boulevard Houston, TX — 1,505,855 — 8,073,136 1,534,644 8,044,347 9,578,991 734,400 2013 5 - 40 1283 N Post Oak Rd Houston, TX — * 80,730 870,656 146,624 80,730 1,017,280 1,098,010 228,608 2013 5 - 40 1287 N Post Oak Rd Houston, TX — * 146,654 1,620,780 63,282 146,654 1,684,061 1,830,715 334,126 2013 5 - 40 1291 N Post Oak Rd Houston, TX — * 510,102 4,129,042 602,376 510,102 4,731,418 5,241,520 938,895 2013 5 - 40 1416 N Sam Houston Parkway E Houston, TX — * 218,850 1,639,902 569,056 218,850 2,208,957 2,427,807 517,674 2013 5 - 40 LIBERTY PROPERTY TRUST AND LIBERTY PROPERTY LIMITED PARTNERSHIP SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION AS OF DECEMBER 31, 2018 Initial Cost Gross Amount Carried at End of Period Project Location Encumbrances (1) Land Building Costs Capitalized Subsequent to Acquisition (2) Land and Improvements Building and Improvements Total 12/31/2018 Accumulated Depreciation 12/31/2018 Date of Construction or Acquisition Depreciable life (years) OPERATING PROPERTIES 1420 N Sam Houston Parkway E Houston, TX — * 211,279 1,554,156 291,238 211,279 1,845,394 2,056,673 308,944 2013 5 - 40 14200 Hollister Road Houston, TX — 1,396,794 — 4,960,165 1,699,632 4,657,327 6,356,959 792,722 2011 5 - 40 1424 N Sam Houston Parkway E Houston, TX — * 283,107 2,077,323 423,815 283,107 2,501,138 2,784,245 488,242 2013 5 - 40 1428 N Sam Houston Parkway E Houston, TX — * 367,446 1,952,453 464,576 367,446 2,417,028 2,784,474 450,680 2013 5 - 40 14300 Hollister Road Houston, TX — * 1,377,193 — 5,613,585 1,388,292 5,602,486 6,990,778 850,061 2014 5 - 40 14400 Hollister Road Houston, TX — * 1,830,419 — 7,162,866 1,838,166 7,155,119 8,993,285 2,203,839 2012 5 - 40 15102 Sommermeyer St Houston, TX — 755,121 3,155,774 249,394 755,121 3,405,168 4,160,289 661,680 2013 5 - 40 15150 Sommermeyer St Houston, TX — 418,580 1,564,587 264,824 418,580 1,829,411 2,247,991 391,559 2013 5 - 40 16330 Central Green Boulevard Houston, TX — 1,540,109 — 8,519,116 1,966,472 8,092,753 10,059,225 1,011,409 2014 5 - 40 16405 Air Center Boulevard Houston, TX — 438,853 3,030,396 1,194,986 438,853 4,225,382 4,664,235 2,053,640 1997 5 - 40 16420 West Hardy Road Houston, TX — 529,876 3,267,872 374,162 529,876 3,642,034 4,171,910 701,597 2013 5 - 40 16445 Air Center Boulevard Houston, TX — 363,339 2,509,186 325,072 363,339 2,834,258 3,197,597 1,436,619 1997 5 - 40 1646 Rankin Road Houston, TX — 329,961 — 5,033,129 592,234 4,770,856 5,363,090 1,690,069 2005 5 - 40 1655 Townhurst Drive Houston, TX — * 197,226 935,036 566,781 197,226 1,501,817 1,699,043 420,556 2013 5 - 40 16580 Air Center Boulevard Houston, TX — 289,000 3,559,857 1,325,263 289,000 4,885,121 5,174,121 2,243,816 1997 5 - 40 16602 Central Green Boulevard Houston, TX — 284,403 — 5,462,498 503,779 5,243,122 5,746,901 1,824,292 2005 5 - 40 16605 Air Center Boulevard Houston, TX — 298,999 — 3,423,751 496,186 3,226,564 3,722,750 1,357,158 2002 5 - 40 1665 Townhurst Drive Houston, TX — * 452,439 2,016,585 594,268 452,439 2,610,852 3,063,291 462,530 2013 5 - 40 16680 Central Green Boulevard Houston, TX — 311,952 — 3,714,116 492,869 3,533,199 4,026,068 957,760 2001 5 - 40 16685 Air Center Boulevard Houston, TX — 414,691 — 2,459,178 414,691 2,459,178 2,873,869 884,382 2004 5 - 40 1755 Trans Central Drive Houston, TX — 293,534 3,036,269 1,476,893 306,147 4,500,549 4,806,696 1,863,536 1999 5 - 40 4301 S Pinemont Dr Houston, TX — * 226,973 1,174,979 174,177 226,973 1,349,156 1,576,129 349,730 2013 5 - 40 4401 S Pinemont Dr Houston, TX — * 244,240 1,412,622 247,951 244,240 1,660,573 1,904,813 397,128 2013 5 - 40 4501 S Pinemont Dr Houston, TX — * 252,907 1,504,053 229,239 252,907 1,733,292 1,986,199 291,990 2013 5 - 40 5200 N. Sam Houston Parkway Houston, TX — 1,519,458 7,135,548 4,015,803 1,520,074 11,150,735 12,670,809 3,864,134 2007 5 - 40 5250 N. Sam Houston Parkway Houston, TX — 2,173,287 8,868,256 3

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share, Basic and Diluted [Line Items]
Organization	ORGANIZATION Liberty Property Trust (the “Trust”) is a self-administered and self-managed Maryland real estate investment trust (a “REIT”). Substantially all of the Trust’s assets are owned directly or indirectly, and substantially all of the Trust’s operations are conducted directly or indirectly, by its subsidiary, Liberty Property Limited Partnership, a Pennsylvania limited partnership (the “Operating Partnership” and, together with the Trust and their consolidated subsidiaries, the “Company”). The Trust is the sole general partner and also a limited partner of the Operating Partnership, owning 97.7% of the common equity of the Operating Partnership at December 31, 2018 . The Company owns and operates industrial properties in the United States nationally, as well as in the United Kingdom. The Company intends to divest its remaining office properties (other than its headquarters) over the next few years and focus its efforts and capital solely on its industrial platform. Unless otherwise indicated, the notes to the Consolidated Financial Statements apply to both the Trust and the Operating Partnership. The terms the "Company,” “we,” “our” and “us” means the Trust and Operating Partnership collectively.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("US GAAP") requires management to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements of the Company include the Trust, the Operating Partnership, wholly owned subsidiaries and those subsidiaries in which the Company owns a majority voting interest with the ability to control operations of the subsidiaries and where no approval, veto or other important rights have been granted to the noncontrolling shareholders. The Company consolidates joint ventures that are considered to be variable interest entities (“VIEs”) where we are the primary beneficiary. The Company (i) evaluates the sufficiency of the total equity investment at risk, (ii) reviews the voting rights and decision-making authority of the equity investment holders as a group and whether there are any guaranteed returns, protection against losses, or capping of residual returns within the group and (iii) establishes whether activities within the venture are on behalf of an investor with disproportionately few voting rights in making this VIE determination. To the extent that the Company (i) is the sole entity that has the power to direct the activities of the VIE and (ii) has the obligation or rights to absorb the VIE's losses or receive its benefits, then the Company would be the primary beneficiary and would consolidate the VIE. All significant intercompany transactions and accounts have been eliminated.
Reclassifications	Reclassifications Certain amounts from prior years have been reclassified to conform to current-year presentation including reclassifying the accompanying consolidated balance sheets for assets held for sale and the consolidated statements of comprehensive income for discontinued operations. In 2018, the Company began to separately classify other operating expenses in the Consolidated Statements of Comprehensive Income. Other operating expenses include expensed pursuit costs, system implementation costs and severance costs. The Company is incurring costs associated with its efforts to implement new financial and operating systems in certain cloud computing arrangements. The Company evaluated the arrangements in accordance with ASU 2015-05 "Customer's Accounting for Fees Paid in a Cloud Computing Arrangement" and concluded that such arrangements are service contracts under the standard. Accordingly, the Company expenses substantially all costs as incurred. Certain costs that relate to the software service agreements received over time are set up as prepaid and expensed over the applicable service period. These costs include license costs during the implementation period as well as consulting, personnel and other direct costs related to the implementation. The Company capitalizes pre-development costs incurred in pursuit of new development opportunities for which the Company currently believes future development is probable. Future development is dependent upon various factors, including zoning and regulatory approval, rental market conditions and construction costs. Initial pre-development costs incurred for pursuits for which future development is not yet considered probable are expensed as incurred. In addition, if the status of a future development by the Company is no longer probable, any capitalized pre-development costs are written off with a charge to expense. Severance costs are incurred in conjunction with certain headcount reductions relating primarily to the Company's change in strategy. Previously, expensed pursuit costs were on a separate line item on the Company's Consolidated Statements of Comprehensive Income in amounts per the table below. Systems implementation costs and severance costs were included in general and administrative expense in amounts as follows (in thousands): 2017 2016 Expensed pursuit costs $ 5,066 $ 1,016 General and administrative expense 1,011 4,001
Concentration of Credit Risk	Concentration of Credit Risk As of December 31, 2018, wholly owned properties were leased to 1,084 customers. The geographic locations that comprise greater than 10% of our segment level operating revenues were Lehigh Valley/Central PA and Carolinas/Richmond. Our customers engage in a wide variety of businesses. No single customer generated more than 4.3% of our consolidated operating rental revenues during 2018. In 2018, the Sears Holdings Corporation filed for reorganization under Chapter 11 of the federal bankruptcy laws. This tenant represents 0.8% of consolidated operating rental revenues during 2018.
Real Estate and Depreciation	Real Estate and Depreciation The properties are recorded at cost and are depreciated using the straight line method over their estimated useful lives. The estimated useful lives are as follows: Building and improvements 40 years (blended) Capital improvements 15 - 20 years Equipment 5 - 10 years Tenant improvements Term of the related lease The Company capitalizes costs associated with development and redevelopment activities, capital improvements, tenant improvements and leasing activities, including compensation costs. Expenditures directly related to the improvement of real estate, including interest and other costs capitalized on development and redevelopment projects and land being readied for development, are included in net real estate and are stated at cost. The Company considers a development property substantially complete upon the completion of tenant build-out, but no later than one year after the completion of major construction activity. These capitalized costs include pre-construction costs essential to the development of the property, construction costs, interest costs, real estate taxes, development related compensation and other costs incurred during the period of development. The determination to capitalize rather than expense costs requires the Company to evaluate the status of the development activity. The total of capitalized compensation costs directly related to development, redevelopment, capital improvements, and tenant improvements for the years ended December 31, 2018 , 2017 and 2016 was $7.1 million , $5.5 million and $7.2 million , respectively. Construction related payables at December 31, 2018 and 2017 were $48.1 million and $49.3 million , respectively. The Company allocates the purchase price of real estate acquired to land, building and improvements and intangibles based on the relative fair value of each component. Lease values for acquired properties are determined based on the present value (using a discount rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to each in-place lease and (ii) management's estimate of fair market lease rates for each corresponding in-place lease ("Market Value Intangible"). Origination values are also assigned to in-place leases, and, where appropriate, value is assigned to customer relationships ("Origination Value Intangible"). Acquisition-related costs for asset acquisitions are capitalized and included in net real estate at cost. Expenditures for maintenance and repairs are charged to operations as incurred. The Company depreciates the amounts allocated to building and improvements over 40 years and amortizes the amounts allocated to intangibles relating to in-place leases, which are included in deferred financing and leasing costs and other liabilities in the accompanying consolidated balance sheets, over the remaining term of the related leases. Market Value Intangible amortization is recorded as rental revenue. Origination Value Intangible amortization is recorded as depreciation and amortization. This calculation includes both the remaining noncancelable period and any bargain renewal option periods. Once a property is designated as held for sale, no further depreciation expense is recorded. The Company evaluates its real estate investments upon occurrence of a significant adverse change in its operations and/or market price, an expectation that the asset will be sold or otherwise disposed of before the end of its estimated useful life, among other factors, to assess whether any impairment indicators are present that affect the recovery of the recorded value. If indicators of impairment are identified, the Company estimates the future undiscounted cash flows from the use and eventual disposition of the property and compares this amount to the carrying value of the property. If any real estate investment is considered impaired, a loss is recognized to reduce the carrying value of the property to its estimated fair value. If held for sale, a property is not considered impaired unless its estimated fair value (less costs to sell) is less than the property's book value at the balance sheet date.
Investments in Unconsolidated Joint Ventures	Investments in Unconsolidated Joint Ventures The Company accounts for its investments in unconsolidated joint ventures using the equity method of accounting as the Company exercises significant influence, but does not control these entities. Under the equity method of accounting, the net equity investment of the Company is reflected in the accompanying consolidated balance sheets and the Company's share of net income from the joint ventures is included in the accompanying consolidated statements of comprehensive income. On a periodic basis, management assesses whether there are any indicators that the value of the Company's investments in unconsolidated joint ventures may be other-than-temporarily-impaired. An investment is impaired only if management's estimate of the value of the investment is less than the carrying value of the investment, and such decline in value is deemed to be other-than-temporary. To the extent impairment has occurred, the loss is measured as the excess of the carrying amount of the investment over the estimated fair value of the investment. The estimated fair value of the investments is determined using a discounted cash flow model which is a Level 3 valuation under ASC 820, " Fair Value Measurement ." The Company considers a number of assumptions that are subject to economic and market uncertainties including, among others, demand for space, competition for tenants, changes in market rental rates, operating costs, capitalization rates, holding periods and discount rates.
Cash and Cash Equivalents	Cash and Cash Equivalents Highly liquid investments with a maturity of three months or less when purchased are classified as cash equivalents.
Restricted Cash	Restricted Cash Restricted cash includes tenant security deposits and escrow funds that the Company maintains pursuant to certain mortgage loans. Restricted cash also includes the undistributed proceeds from the sale of residential land in Kent County, United Kingdom.
Accounts Receivable/Deferred Rent Receivable	Accounts Receivable/Deferred Rent Receivable The Company's accounts receivable are comprised of rents and charges for property operating costs due from tenants. The Company's deferred rent receivable represents the cumulative difference between rent revenue recognized on a straight line basis and contractual payments due under the terms of tenant leases. The Company periodically performs a detailed review of amounts due from tenants to determine if accounts receivable and deferred rent receivable balances are collectible. Based on this review, accounts receivable and deferred rent receivable are reduced by an allowance for doubtful accounts. The Company considers tenant credit quality and payment history and general economic conditions in determining the allowance for doubtful accounts. If the accounts receivable balance or the deferred rent receivable balance is subsequently deemed uncollectible, the receivable and allowance for doubtful account balance are written off.
Revenue Recognition	Revenue Recognition The Company earns rental income under operating leases with tenants. Rental income is recognized on a straight line basis over the applicable non-cancelable lease term. Operating expense reimbursements consisting of amounts due from tenants for real estate taxes, utilities and other recoverable costs are recognized as revenue in the period in which the corresponding expenses are incurred. The Company considers any renewal options in determining the lease term. To the extent a lease includes a tenant option to renew or extend the duration of the lease at a fixed or determinable rental rate, the Company evaluates whether or not that option represents a bargain renewal option by analyzing if there is reasonable assurance at lease inception that the tenant will exercise the option because the rental rate is sufficiently lower than the expected rental rate for equivalent property under similar terms and conditions at the exercise date. Termination fees (included in rental revenue) are fees that the Company has agreed to accept in consideration for permitting certain tenants to terminate their lease prior to the contractual expiration date. The Company recognizes termination fees during the period that landlord services are rendered in accordance with Securities and Exchange Commission Staff Accounting Bulletin 104, " Revenue Recognition ," after the following conditions are met: a. the termination agreement is executed, b. the termination fee is determinable, and c. collectability of the termination fee is assured. Effective January 1, 2018, the Company adopted the "New Revenue Standards," comprised of: ASU 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASU 2014-09”), which supersedes nearly all existing revenue recognition guidance (except revenue in the scope of other accounting standards, including standards related to leasing) as well as the following standards subsequently issued by the FASB related to ASU 2014-09: ASU 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations ; ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing ; ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients ; ASU 2017-05, Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20) , and ASU 2017-13, Revenue from Contracts with Customers (Topic 606): Amendments to SEC Paragraphs Pursuant to the Staff Announcement at the July 20, 2017 EITF Meeting and Rescission of Prior SEC Staff Announcements and Observer Comments. The New Revenue Standards provide a unified model to determine how revenue is recognized. In accordance with the New Revenue Standards, the Company performs the following steps: (i) identify the contract with the customer, (ii) identify the performance obligations within the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations and (v) recognize revenue when (or as) a performance obligation is satisfied. The Company evaluated each of its revenue streams: lease agreement revenue, development service fee revenue, deferred land sale revenue and gain or loss on sale of nonfinancial assets and adopted the New Revenue Standards effective January 1, 2018 using the modified retrospective approach. The Company concluded that there are no revenue streams from its lease agreements that are covered by the New Revenue Standards. The Company adopted the practical expedient to assess the recognition of revenue for open contracts during the transition period. There was no adjustment to the opening balance of retained earnings recorded at January 1, 2018. In the fourth quarter of 2016, the Company entered into an agreement relating to the fee development of an office building at its Camden Waterfront project in Camden, NJ. Project revenues and related costs and expenses are presented on a gross basis as "Development service fee income" and "Development service fee expense" in the Consolidated Statements of Comprehensive Income. Additionally, at the same time, the Company began classifying development fees and expenses relating to its fee development arrangements for certain unconsolidated joint venture projects in a manner consistent with the Camden project described above. Previously, development service fee income relating to its unconsolidated joint ventures had been classified as other income and development service fee expense had been classified as general and administrative expense in amounts as follows: Nine months ended September 30, 2016 (unaudited) Other income $ 3,789 General and administrative expense $ 3,210 For the years ended December 31, 2017 and 2016, revenue and expense associated with service fee development was accounted for under the percentage of completion method. Revenues were recognized on the percentage of completion method based on applicable costs incurred with respect to each development agreement. The Company used the relative sales value method to allocate costs and recognize profits from service fee development. Under the relative sales value method, estimates of aggregate project revenues and aggregate project costs are used to determine the allocation of project cost of sales and the resulting profit in each accounting period. In subsequent periods, cost of sale allocations and the resulting profits are adjusted to reflect changes in the actual and estimated costs and revenues of each project. Provisions for estimated losses on uncompleted contracts are recognized immediately in the period in which such losses are determined. The New Revenue Standards did not have an impact on the amount and timing of recognizing the Company's development service fee income. The Company recognizes development service fee income on a variable basis as a percentage of costs incurred on third party development contracts. Property development services, which are a single performance obligation, continue to be satisfied and recognized over time. The Company measures its progress toward completing the performance obligation under each arrangement. The measurement of the transfer of value to the customer for these services utilizes the input method (actual costs incurred against anticipated project costs) since this method best depicts the actual transfer of value promised to the customer. Estimated expected losses on such contracts are accrued in the period in which they are determinable. The total amount of consideration to be received from these projects is assessed on a quarterly basis. The Company receives cash as it sells improved land sites on behalf of its development partner to home builders in the United Kingdom. These agreements contain a pre-emption clause and a seller's call option. The Company recognizes revenue as the pre-emption period or seller's call option lapses utilizing the output method. There was $2.4 million , $0.3 million , and $2.6 million in revenue recognized for such contracts during the years ended December 31, 2018, 2017 and 2016, respectively. The New Revenue Standards did not have an impact on the gain or loss on sale of nonfinancial assets. The New Revenue Standards require the Company to derecognize nonfinancial assets once it transfers control of a distinct nonfinancial asset or distinct in substance nonfinancial asset. Additionally, when the Company transfers its controlling interest in a nonfinancial asset, but retains a noncontrolling ownership interest, the Company is required to measure any noncontrolling interest it receives or retains at fair value. The guidance requires companies to recognize a full gain or loss on the transaction. See Note 6 - Real Estate, Note 7 - Investments in Unconsolidated Joint Ventures and Note 19 - Accounting for the Impairment or Disposal of Long-lived Assets for further discussion of sales of nonfinancial assets. Estimated gross revenue related to the remaining performance obligations under existing contracts (before allocation of related costs and expenses) as of December 31, 2018 that will be recognized as revenue in future periods was approximately $37.1 million , which is expected to be recognized through 2021.
Deferred Financing and Leasing Costs	Deferred Financing and Leasing Costs Costs incurred in connection with leasing or financing of the credit facilities are capitalized and amortized on a straight line basis over the term of the related lease or loan. Costs incurred in connection with the financing of mortgage loans or unsecured notes are reported as a deduction from the face amount of that liability and amortized on a straight line basis over the term of the related loan. Deferred financing cost amortization is reported as interest expense. Certain employees of the Company are compensated for leasing services related to the Company's properties. The compensation directly related to these leasing services is capitalized and amortized as a deferred leasing cost over the term of the related lease.
Fair Value of Financial Instruments	Fair Value of Financial Instruments ASC 820, Fair Value Measurements and Disclosures , gives guidance on the fair value measurement of a financial asset or liability. Inputs used to develop fair value are classified in one of three categories: Level 1 inputs (quoted prices (unadjusted) in active markets for identical assets or liabilities), Level 2 inputs (inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly) and Level 3 inputs (unobservable inputs for the asset or liability). The following disclosure of estimated fair value was determined by management using available market information and appropriate valuation methodologies. However, considerable judgment is necessary to interpret market data and develop estimated fair value. Accordingly, the following estimates are not necessarily indicative of the amounts the Company could have realized on disposition of the financial instruments at December 31, 2018 and December 31, 2017 . The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. The carrying value of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accrued interest, dividend and distributions payable and other liabilities are reasonable estimates of fair value because of the short-term nature of these instruments. The carrying value of the outstanding amounts under the Company's credit facilities is also a reasonable estimate of fair value because interest rates float at a rate based on LIBOR. The Company determines the fair value of its interest rate swaps by using the standard methodology of netting discounted future fixed cash payments with the discounted expected variable cash receipts. These variable cash receipts of interest rate swaps are based on expectations of future LIBOR interest rates (forward curves) estimated by observing market LIBOR interest rate curves. This is a Level 2 fair value calculation. Also, credit valuation adjustments are factored into the fair value calculations to account for potential nonperformance risk. These credit valuation adjustments were concluded to be not significant inputs for the fair value calculations for the periods presented. See Note 20 - Derivative Instruments. The Company used a discounted cash flow model to determine the estimated fair value of its debt as of December 31, 2018 and December 31, 2017 . This is a Level 3 fair value calculation. The inputs used in preparing the discounted cash flow model include actual maturity dates and scheduled cash flows as well as estimates for market value discount rates. The Company updates the discounted cash flow model on a quarterly basis to reflect any changes in the Company's debt holdings and changes to discount rate assumptions.
Income Taxes	Income Taxes The Company has elected to be taxed as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the "Code"). As a result, the Company generally is not subject to federal income taxation at the corporate level to the extent it distributes annually at least 100% of its REIT taxable income, as defined in the Code, to its shareholders and satisfies certain other organizational and operational requirements. The Company has met these requirements and, accordingly, no provision has been made for federal income taxes in the accompanying consolidated financial statements. If the Company fails to qualify as a REIT in any taxable year, the Company will be subject to federal income tax on its taxable income at regular corporate rates (including any alternative minimum tax for those tax years beginning prior to January 1, 2018) and may not be able to qualify as a REIT for the four subsequent taxable years. Even as a REIT, the Company may still be subject to certain state and local income and property taxes, and to federal income and excise taxes on undistributed taxable income. The Company continues to consider and implement the relevant provisions of the Tax Cuts and Jobs Act (the "TCJA"), which was signed into law on December 22, 2017 and which generally took effect for taxable years beginning on or after January 1, 2018. Based upon its assessment, when combined with the guidance issued to date by both the Internal Revenue Service and the United States Treasury Department, the Company does not reasonably believe or expect those provisions, or the TCJA in general, will have a material impact on its overall financial condition, business operations or ability to continue to qualify as a REIT on a going forward basis. Several of the Company's subsidiaries are taxable REIT subsidiaries (each a "TRS") and are subject to federal and state income taxes separate from the Company. In general, a TRS may perform additional services for tenants and generally may engage in real estate or non-real estate businesses that are not permitted REIT activities. The Company itself is also subject to tax in certain states and the United Kingdom. Accordingly, the Company recognizes federal, state and foreign income taxes in accordance with US GAAP, as applicable. In addition, the TCJA implemented a one-time deemed repatriation tax on offshore corporate profits, including any such profits which the Company may have accumulated over the years in its offshore TRSs, at the reduced rates of 15.5% on cash assets and 8% on noncash assets. The Company has reviewed its accumulated offshore earnings through December 31, 2017 and this provision of the TCJA did not have a material impact on the Company’s overall financial condition or results of operation or its 2017 federal and state tax return filings. Currently there are no uncertain tax positions or possibly significant unrecognized tax benefits that are reasonably expected to occur within the next 12 months. The Company's policy is to recognize interest accrued related to unrecognized benefits in interest expense and penalties in other expense. There were no interest or penalties deducted in any of the years ended December 31, 2018 , 2017 and 2016 and no interest and penalties accrued at December 31, 2018 or December 31, 2017 which related to any uncertain tax positions or significant unrecognized tax benefits. As of December 31, 2018, certain of the Company's TRSs have estimated net operating loss ("NOL") carryforwards available of approximately $20.8 million . Unless reduced or utilized, these NOL carryforwards are set to begin expiring in 2020 . Additionally, the TCJA reduced the corporate federal tax rate in the U.S. from 35% to 21% effective for tax years beginning after December 31, 2017 while also reducing the amount of newly generated NOLs that can generally be utilized by a taxpayer in any tax year from 100% of net taxable income to 90%. As such, deferred tax assets and liabilities, where applicable, were remeasured to account for these changes. After taking into consideration the projected future net taxable income at these entities, and consistent with prior periods, the Company has determined that a valuation allowance for the full carrying value of NOL carryforwards is appropriate. The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction, certain state and local jurisdictions, the United Kingdom and (in prior years) Luxembourg. With few exceptions, the Company and its subsidiaries are no longer subject to examination by taxing authorities in these jurisdictions for years prior to 2012.
Share-based Compensation	Share-Based Compensation Share-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as expense over the employees' requisite service period. The Company recognizes forfeitures on share based compensation as they occur.
Derivative Financial Instruments	Derivative Financial Instruments The Company borrows funds at a combination of fixed and variable rates. Borrowings under our Facilities and certain bank mortgage loans bear interest at variable rates. Our long-term debt typically bears interest at fixed rates. Our interest rate risk management objectives are to limit generally the impact of interest rate changes on earnings and cash flows and to lower our overall borrowing costs. To achieve these objectives, from time to time, we enter into interest rate hedge contracts such as collars, swaps, caps and treasury lock agreements in order to mitigate our interest rate risk with respect to various debt instruments. We generally do not hold or issue these derivative contracts for trading or speculative purposes. The interest rate on all of our variable rate debt is generally adjusted at one or three month intervals, subject to settlements under interest rate hedge contracts. Interest rate swaps involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive loss (for the Trust) and general partner's equity and limited partners' equity - common units (for the Operating Partnership) and is subsequently reclassified into interest expense in the period that the hedged forecasted transaction affects earnings.
Foreign Currency	Foreign Currency The functional currency of the Company's United Kingdom operations is pounds sterling. The Company translates the financial statements for the United Kingdom operations into US dollars. For the Trust, gains and losses resulting from this translation are included in accumulated other comprehensive loss as a separate component of shareholders' equity and a proportionate amount of gain or loss is allocated to noncontrolling interest - operating partnership - common units. For the Operating Partnership, gains and losses resulting from this translation are included in general partner's equity and limited partners' equity - common units. Upon sale or upon complete or substantially complete liquidation of the Company's foreign investment, the gain or loss on the sale will include the cumulative translation adjustments that have been previously recorded in accumulated other comprehensive loss and noncontrolling interest - operating partnership - common units (for the Trust) and in general partner's equity and limited partners' equity - common units (for the Operating Partnership).
Comprehensive Income	Comprehensive Income Comprehensive income, as reflected on the consolidated statements of comprehensive income, is defined as all changes in equity during each period except for those resulting from investments by or distributions to shareholders. Accumulated other comprehensive loss, as reflected on the Company's consolidated balance sheets and consolidated statements of equity, reflects the effective portion of the cumulative changes in the fair value of derivatives in qualifying cash flow hedge relationships as well as gains and losses resulting from foreign currency translation.
Earnings Per Share/Unit	Earnings Per Share of the REIT Basic earnings per share is calculated by dividing the income available to common shareholders for the period by the weighted average number of common shares outstanding during the period using the two class method. Diluted earnings per share is calculated by dividing the net income available to common shareholders for the period by the weighted average number of common and dilutive securities outstanding during the period.
Recently Issued Accounting Standards	Recently Issued Accounting Standards Leases In February 2016, the FASB issued ASU 2016-02, Leases (“ASU 2016-02”). Subsequently the FASB issued the following standards related to ASU 2016-02: ASU 2018-10, Codification Improvements to Topic 842, Leases and ASU 2018-11, Leases (Topic 842) : Targeted Improvements (collectively, the "New Lease Standard"). The New Lease Standard amends the existing accounting standards for lease accounting, including requiring lessees to recognize most leases on their balance sheets and making targeted changes to lessor accounting. The New Lease Standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for sales-type leases, direct financing leases and operating leases. In addition, the New Lease Standard limits the capitalization of costs by lessors to incremental direct leasing costs. Therefore the Company will no longer capitalize and amortize certain leasing related costs and instead will expense these costs as incurred. Such capitalized costs were approximately $1 million for the year ended December 31, 2018. The New Lease Standard provides lessors a practical expedient to not separate lease and non-lease components if certain criteria are met. The Company assessed these criteria and concluded that the timing and pattern of transfer for non-lease components and lease components are the same, and therefore will account for and present rental revenue and operating expense reimbursements as a single component. The Company is a lessee of ground and office space leases. In accordance with the New Lease Standard, for lease agreements longer than one year, the Company will measure the present value of the future lease payments and recognize a right-of-use asset and corresponding lease liability on its balance sheet estimated to range from $18 million to $20 million . The Company adopted the New Lease standard on January 1, 2019 and applied it prospectively. The following practical expedients available for implementation were elected: a. whether an expired or existing contract meets the definition of a lease b. the lease classification at the adoption date for existing or expired leases c. whether costs previously capitalized as initial direct costs would continue to be amortized The Company therefore does not expect an adjustment to the opening balance of retained earnings. Other In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 is designed to clarify how entities should classify cash receipts and cash payments in the statement of cash flows. ASU 2016-15 became effective for the Company beginning January 1, 2018. The standard requires retrospective application. The adoption of ASU 2016-15 did not have a material impact on the Company's consolidated financial statements. In February 2017, the FASB issued ASU 2017-05, Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets ("ASU 2017-05"). ASU 2017-05 is designed to provide guidance on how to recognize gain and losses on sales, including partial sale, of nonfinancial assets to noncustomers. The Company adopted ASU 2017-05 effective January 1, 2018 on a modified retrospective method and the adoption did not have an effect on the Company’s consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting ("ASU 2017-09"). ASU 2017-09 clarifies when changes to the terms or conditions of a share-based payment award must be accounted for as modifications. ASU 2017-09 became effective for the Company beginning January 1, 2018. The new guidance was applied prospectively to awards modified on or after the adoption date. The adoption of ASU 2017-09 did not have a material impact on the consolidated financial statements. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities ("ASU 2017-12"). ASU 2017-12 is designed to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for the Company beginning January 1, 2019. Early adoption is permitted using a modified retrospective transition method. This adoption method will require the Company to recognize the cumulative effect of initially applying ASU 2017-12 as an adjustment to accumulated other comprehensive income with a corresponding adjustment to the opening balance of retained earnings as of the beginning of the fiscal year that an entity adopts the update. The Company does not believe the adoption of the ASU 2017-12 will have a material impact on the consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software: Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract ("ASU 2018-15"). ASU 2018-15 amends the definition of a hosting arrangement and requires a customer in a hosting arrangement that is a service contract to capitalize certain implementation costs as if the arrangement was an internal-use software project. ASU 2018-15 is effective for the Company beginning January 1, 2020. Upon adoption, the Company does not anticipate the impact of ASU 2018-15 will have a material impact on the consolidated financial statements. In August 2018, the Securities and Exchange Commission adopted a final rule that eliminated or amended disclosure requirements that were redundant or outdated in light of changes in its requirements, GAAP, or changes in the business environment. The commission also referred certain disclosure requirements to the FASB for potential incorporation into GAAP. The rule is effective for filings after November 5, 2018. The Company assessed the impact of this rule and determined that the changes resulted in clarification or expansion of existing requirements. The Company adopted the rule and it did not have a material impact on the Company’s consolidated financial statements.
Discontinued Operations	In 2017, the Company initiated a strategic shift whereby it plans to divest of its remaining suburban office properties. In 2018, the Company updated its strategy whereby it plans to divest of its remaining office properties. The Company determined that the strategic shift would have a major effect on its operations and financial results. As such, properties sold or those that meet the criteria to be classified as held for sale within the new corporate strategy were classified within discontinued operations. Consistent with the held for sale criteria these properties are expected to be sold within one year. As the result of the classification within discontinued operations, the in-service assets and liabilities of this portfolio are required to be presented as held for sale for all prior periods presented in our Consolidated Balance Sheets. Operating results pertaining to these properties were reclassified to discontinued operations for all prior periods presented in our Consolidated Statements of Comprehensive Income.
Interest Expense Allocated to Discontinued Operations	Interest expense has been allocated to discontinued operations. The allocation of interest expense to discontinued operations was based on the ratio of net assets sold and held for sale (without continuing involvement) to the sum of total net assets plus consolidated debt.
Accounting for the Impairment or Disposal of Long-Lived Assets	The Company determined the above-described impairments based on third party offer prices and quoted offer prices for comparable transactions which are Level 2 and Level 3 inputs, respectively, according to the fair value hierarchy established in ASC 820. These measurements have occurred throughout the respective periods as circumstances arise, and the resulting estimates of fair value are not necessarily reflective of measurements at the period’s end. The Company has evaluated each of its properties and land held for development and has determined that there were no additional valuation adjustments necessary at December 31, 2018 . The Company applied reasonable estimates and judgments in determining the level of impairments recognized. Should external or internal circumstances change requiring the need to shorten the holding periods or adjust the estimated future cash flows of the Company’s assets, the Company could be required to record impairment charges in the future.
Liberty Property Limited Partnership
Earnings Per Share, Basic and Diluted [Line Items]
Earnings Per Share/Unit	Earnings Per Unit of the Operating Partnership Basic earnings per unit is calculated by dividing the income available to common unitholders for the period by the weighted average number of common units outstanding during the period using the two class method. Diluted earnings per unit is calculated by dividing the income available to common unitholders for the period by the weighted average number of common and dilutive securities outstanding during the period.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
System implementation costs and severance costs	Systems implementation costs and severance costs were included in general and administrative expense in amounts as follows (in thousands): 2017 2016 Expensed pursuit costs $ 5,066 $ 1,016 General and administrative expense 1,011 4,001
Schedule of Property Deprecation	The properties are recorded at cost and are depreciated using the straight line method over their estimated useful lives. The estimated useful lives are as follows: Building and improvements 40 years (blended) Capital improvements 15 - 20 years Equipment 5 - 10 years Tenant improvements Term of the related lease
Schedule of Adjustment to Previously Reported Consolidated Financial Statements	Previously, development service fee income relating to its unconsolidated joint ventures had been classified as other income and development service fee expense had been classified as general and administrative expense in amounts as follows: Nine months ended September 30, 2016 (unaudited) Other income $ 3,789 General and administrative expense $ 3,210
Schedule of Fair Value of Mortgage Loans and Unsecured Notes	The following summarizes the fair value of the Company's mortgage loans and unsecured notes at December 31, 2018 and December 31, 2017 (in thousands): Mortgage Loans Unsecured Notes Carrying Value Fair Value Carrying Value Fair Value As of December 31, 2018 $ 395,202 $ 397,167 $ 2,285,698 $ 2,295,699 As of December 31, 2017 $ 267,093 $ 267,298 $ 2,283,513 $ 2,359,998

Income per Common Share of th_2

Income per Common Share of the Trust (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted income per common share of the Trust (in thousands except per share amounts): 2018 2017 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 160,677 147,275 $ 1.09 $ 242,066 146,742 $ 1.65 Dilutive shares for long-term compensation plans — 946 — 799 Income from continuing operations net of noncontrolling interest - diluted $ 160,677 148,221 $ 1.09 $ 242,066 147,541 $ 1.64 Discontinued operations net of noncontrolling interest - basic $ 318,930 147,275 $ 2.17 $ 40,274 146,742 $ 0.27 Dilutive shares for long-term compensation plans — 946 — 799 Discontinued operations net of noncontrolling interest - diluted $ 318,930 148,221 $ 2.15 $ 40,274 147,541 $ 0.27 Net income available to common shareholders - basic $ 479,607 147,275 $ 3.26 $ 282,340 146,742 $ 1.92 Dilutive shares for long-term compensation plans — 946 — 799 Net income available to common shareholders - diluted $ 479,607 148,221 $ 3.24 $ 282,340 147,541 $ 1.91 2016 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 330,320 146,204 $ 2.26 Dilutive shares for long-term compensation plans — 685 Income from continuing operations net of noncontrolling interest - diluted $ 330,320 146,889 $ 2.25 Discontinued operations net of noncontrolling interest - basic $ 26,497 146,204 $ 0.18 Dilutive shares for long-term compensation plans — 685 Discontinued operations net of noncontrolling interest - diluted $ 26,497 146,889 $ 0.18 Net income available to common shareholders - basic $ 356,817 146,204 $ 2.44 Dilutive shares for long-term compensation plans — 685 Net income available to common shareholders - diluted $ 356,817 146,889 $ 2.43

Income per Common Unit of the_2

Income per Common Unit of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Unit, Basic and Diluted [Line Items]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted income per common share of the Trust (in thousands except per share amounts): 2018 2017 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 160,677 147,275 $ 1.09 $ 242,066 146,742 $ 1.65 Dilutive shares for long-term compensation plans — 946 — 799 Income from continuing operations net of noncontrolling interest - diluted $ 160,677 148,221 $ 1.09 $ 242,066 147,541 $ 1.64 Discontinued operations net of noncontrolling interest - basic $ 318,930 147,275 $ 2.17 $ 40,274 146,742 $ 0.27 Dilutive shares for long-term compensation plans — 946 — 799 Discontinued operations net of noncontrolling interest - diluted $ 318,930 148,221 $ 2.15 $ 40,274 147,541 $ 0.27 Net income available to common shareholders - basic $ 479,607 147,275 $ 3.26 $ 282,340 146,742 $ 1.92 Dilutive shares for long-term compensation plans — 946 — 799 Net income available to common shareholders - diluted $ 479,607 148,221 $ 3.24 $ 282,340 147,541 $ 1.91 2016 Income (Numerator) Weighted Average Shares (Denominator) Per Share Income from continuing operations net of noncontrolling interest - basic $ 330,320 146,204 $ 2.26 Dilutive shares for long-term compensation plans — 685 Income from continuing operations net of noncontrolling interest - diluted $ 330,320 146,889 $ 2.25 Discontinued operations net of noncontrolling interest - basic $ 26,497 146,204 $ 0.18 Dilutive shares for long-term compensation plans — 685 Discontinued operations net of noncontrolling interest - diluted $ 26,497 146,889 $ 0.18 Net income available to common shareholders - basic $ 356,817 146,204 $ 2.44 Dilutive shares for long-term compensation plans — 685 Net income available to common shareholders - diluted $ 356,817 146,889 $ 2.43
Liberty Property Limited Partnership
Earnings Per Unit, Basic and Diluted [Line Items]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted income per common unit of the Operating Partnership (in thousands, except per unit amounts): 2018 2017 Income (Numerator) Weighted Average Units (Denominator) Per Unit Income (Numerator) Weighted Average Units (Denominator) Per Unit Income from continuing operations - net of noncontrolling interest - consolidated joint ventures $ 164,955 $ 248,325 Less: Preferred unit distributions (472 ) (472 ) Income from continuing operations available to common unitholders - basic $ 164,483 150,795 $ 1.09 $ 247,853 150,270 $ 1.65 Dilutive units for long-term compensation plans — 946 — 799 Income from continuing operations available to common unitholders - diluted $ 164,483 151,741 $ 1.09 $ 247,853 151,069 $ 1.64 Income from discontinued operations - basic $ 326,538 150,795 $ 2.17 $ 41,239 150,270 $ 0.27 Dilutive units for long-term compensation plans 946 799 Income from discontinued operations - diluted $ 326,538 151,741 $ 2.15 $ 41,239 151,069 $ 0.27 Income available to common unitholders - basic $ 491,021 150,795 $ 3.26 $ 289,092 150,270 $ 1.92 Dilutive units for long-term compensation plans 946 799 Income available to common unitholders - diluted $ 491,021 151,741 $ 3.24 $ 289,092 151,069 $ 1.91 2016 Income (Numerator) Weighted Average Units (Denominator) Per Unit Income from continuing operations net of noncontrolling interest - consolidated joint ventures $ 338,758 Less: Preferred unit distributions (472 ) Income from continuing operations available to common unitholders - basic $ 338,286 149,740 $ 2.26 Dilutive units for long-term compensation plans — 685 Income from continuing operations available to common unitholders - diluted $ 338,286 150,425 $ 2.25 Income from discontinued operations - basic $ 27,129 149,740 $ 0.18 Dilutive units for long-term compensation plans — 685 Income from discontinued operations - diluted $ 27,129 150,425 $ 0.18 Income available to common unitholders - basic $ 365,415 149,740 $ 2.44 Dilutive units for long-term compensation plans — 685 Income available to common unitholders - diluted $ 365,415 150,425 $ 2.43

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Loss	The following table sets forth the components of Accumulated Other Comprehensive Loss (in thousands): December 31, 2018 2017 Foreign Currency Translation: Beginning balance $ (38,701 ) $ (56,767 ) Translation adjustment (14,161 ) 18,066 Ending balance (52,862 ) (38,701 ) Derivative Instruments: Beginning balance 150 (455 ) Unrealized (loss) gain (3,472 ) 152 Reclassification adjustment (1) (228 ) 453 Ending balance (3,550 ) 150 Total accumulated other comprehensive loss (56,412 ) (38,551 ) Less: portion included in noncontrolling interest – operating partnership 1,169 754 Total accumulated other comprehensive loss included in shareholders' equity $ (55,243 ) $ (37,797 ) (1) Amounts reclassified out of Accumulated Other Comprehensive Loss/General & Limited Partner's Equity into contractual interest expense.

Real Estate (Tables)

Real Estate (Tables)	12 Months Ended
	Dec. 31, 2018
Real Estate [Abstract]
Schedule of Carrying Value of Properties	The carrying value of these operating properties by type as of December 31, 2018 and 2017 is as follows (in thousands): Land Building and Land and Accumulated Improvements Improvements Total Depreciation 2018 Industrial properties $ 1,233,655 $ 4,353,225 $ 5,586,880 $ 926,703 Office properties 23,051 302,559 325,610 48,269 2018 Total $ 1,256,706 $ 4,655,784 $ 5,912,490 $ 974,972 2017 Industrial properties $ 1,000,810 $ 3,867,834 $ 4,868,644 $ 810,044 Office properties 22,743 245,329 268,072 41,580 2017 Total $ 1,023,553 $ 4,113,163 $ 5,136,716 $ 851,624
Schedule of Disposal Groups, Including Discontinued Operations	Information on the operating properties the Company sold during the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Carolinas/Richmond 1 1.5 80,000 $ 7,094 Chicago/Minneapolis — 8.3 — 2,714 Lehigh/Central PA — 66.2 — 9,700 Philadelphia 1 3.1 207,779 130,818 Southeastern PA 32 — 2,325,039 402,708 United Kingdom — — — 65,334 (1) Other 5 — 805,746 255,000 Total 39 79.1 3,418,564 $ 873,368 (1) The Company sold development rights in Horsham, UK. 2017 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 3 — 136,110 $ 8,917 Florida — 16.4 — 13,256 Houston 1 42.2 206,808 36,145 Lehigh/Central PA 2 44.3 1,683,876 249,045 Southeastern PA 4 3.0 313,410 56,156 Other — 7.2 — 3,739 Total 10 113.1 2,340,204 $ 367,258 2016 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 24 5.3 2,037,275 $ 199,825 Florida 51 12.1 3,509,641 505,828 Lehigh/Central PA 1 — 120,777 11,200 Philadelphia — 1.0 — 2,640 Southeastern PA 31 — 2,165,002 266,821 Other 18 18.0 1,631,295 224,241 Total 125 36.4 9,463,990 $ 1,210,555 The following table illustrates the number of sold or held-for-sale properties included in, or excluded from, discontinued operations in this report: Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Total Properties included in discontinued operations 10 37 2 49 Properties included in continuing operations 1 2 8 11 Properties sold or classified as held for sale 11 39 10 60 The following table illustrates the number of sold or held-for-sale properties included in discontinued operations by reportable segment: Reportable Segment Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Florida 3 — — Houston — — 1 Southeastern PA 5 32 1 Other 2 5 — Total 10 37 2 The following table illustrates aggregate balance sheet information for all held-for-sale properties (in thousands): December 31, 2018 December 31, 2017 Included in Continuing Operations Included in Discontinued Operations Total Included in Continuing Operations Included in Discontinued Operations Total Land and land improvements $ 1,301 $ 92,889 $ 94,190 $ 3,476 $ 155,974 $ 159,450 Buildings and improvements 5,638 126,001 131,639 80,738 493,615 574,353 Development in progress — — — — 45,035 45,035 Land held for development 26,253 — 26,253 863 — 863 Accumulated depreciation (1,546 ) (36,569 ) (38,115 ) (11,785 ) (187,335 ) (199,120 ) Deferred financing and leasing costs, net 58 2,781 2,839 2,210 15,296 17,506 Other assets 164 3,575 3,739 5,137 19,351 24,488 Assets held for sale $ 31,868 $ 188,677 $ 220,545 $ 80,639 $ 541,936 $ 622,575 Liabilities held for sale $ 141 $ 3,042 $ 3,183 $ 1,153 $ 13,470 $ 14,623 A summary of the results of operations for the properties classified as discontinued operations through the respective disposition dates is as follows (in thousands): For the Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Revenue Rental $ 43,393 $ 61,405 $ 48,343 Operating expense reimbursement 12,663 27,024 23,042 Total Revenue 56,056 88,429 71,385 Expenses Rental property 6,959 17,826 13,783 Real estate taxes 7,354 11,582 6,873 Other operating expense (9 ) (272 ) 110 Interest expense 5,812 6,858 9,950 Depreciation and amortization 5,356 19,190 13,642 Impairment charges - real estate assets 7,257 6,686 — Total Expense 32,729 61,870 44,358 Interest and other income 52 102 104 Gain on property dispositions 303,159 14,578 — Income taxes — — (2 ) Income from discontinued operations 326,538 41,239 27,129 Noncontrolling interest - operating partnership (7,608 ) (965 ) (632 ) Income available to common shareholders $ 318,930 $ 40,274 $ 26,497
Schedule of Operating Properties and Land Parcels Acquired	Information on the operating properties and land parcels the Company acquired during the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Florida — 30.8 — $ 15,478 Lehigh/Central PA — 170.2 — 34,092 Southern California 5 36.0 1,450,041 291,916 United Kingdom 7 8.7 1,116,421 149,582 Other 4 29.2 1,484,612 141,502 Total 16 274.9 4,051,074 $ 632,570 2017 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Carolinas/Richmond — 10.7 — $ 1,242 Lehigh/Central PA — 94.6 — 17,798 Southern California 3 — 1,163,233 176,310 United Kingdom — 34.6 — 12,550 Other 5 113.6 698,646 88,498 Total 8 253.5 1,861,879 $ 296,398 2016 Acquisitions Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Purchase Price (in thousands) Carolinas/Richmond — 12.7 — $ 2,251 Chicago/Minneapolis 1 5.6 73,160 11,064 Lehigh/Central PA — 76.0 — 15,395 Philadelphia — 6.2 — 13,943 Southeastern PA — 8.3 — 3,344 Southern California — 8.1 — 4,041 Other — 99.5 — 10,854 Total 1 216.4 73,160 $ 60,892

Investments in Unconsolidated_2

Investments in Unconsolidated Joint Ventures (Tables)	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Condensed Balance Sheet of Equity Method Investments	The condensed balance sheets as of December 31, 2018 and 2017 and condensed statements of operations for the years ended December 31, 2018 , 2017 and 2016 for Liberty Venture I LP, Kings Hill Unit Trust, Liberty Illinois, LP, Liberty Washington LP, Liberty/Comcast, Liberty Property 18th & Arch, and the other unconsolidated joint ventures are as follows (in thousands): Condensed Balance Sheets: December 31, 2018 Liberty Kings Hill Liberty Liberty Liberty/ Liberty Property Venture I, LP Unit Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other Total Real estate assets $ 251,648 $ 144,742 $ 252,751 $ 210,732 $ 497,623 $ 688,537 $ 98,659 $ 2,144,692 Accumulated depreciation (54,373 ) (30,554 ) (61,593 ) (15,009 ) (152,169 ) (21,160 ) (12,991 ) (347,849 ) Real estate assets, net 197,275 114,188 191,158 195,723 345,454 667,377 85,668 1,796,843 Development in progress — — — — — 192,568 7,675 200,243 Land held for development — — 33,769 — — — 39,728 73,497 Other assets 23,180 12,141 14,662 17,146 43,671 152,845 29,085 292,730 Total assets $ 220,455 $ 126,329 $ 239,589 $ 212,869 $ 389,125 $ 1,012,790 $ 162,156 $ 2,363,313 Debt $ 170,743 $ 84,691 $ 138,964 $ 101,532 $ — $ — $ 74,081 $ 570,011 Related party debt — 20,239 — — 304,000 — — 324,239 Other liabilities 3,782 8,537 7,304 3,719 8,292 118,953 9,014 159,601 Equity 45,930 12,862 93,321 107,618 76,833 893,837 79,061 1,309,462 Total liabilities and equity $ 220,455 $ 126,329 $ 239,589 $ 212,869 $ 389,125 $ 1,012,790 $ 162,156 $ 2,363,313 Company's net investment in unconsolidated joint ventures (1) $ 9,516 $ 6,230 $ 13,863 $ 27,020 $ 75,102 $ 191,430 $ 27,820 $ 350,981 December 31, 2017 Liberty Kings Hill Liberty Liberty Liberty/ Liberty Property Venture I, LP Unit Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other Total Real estate assets $ 229,600 $ 152,998 $ 252,593 $ 274,847 $ 496,210 $ 551,874 $ 98,589 $ 2,056,711 Accumulated depreciation (48,629 ) (30,028 ) (57,444 ) (49,106 ) (138,943 ) (4,070 ) (10,995 ) (339,215 ) Real estate assets, net 180,971 122,970 195,149 225,741 357,267 547,804 87,594 1,717,496 Development in progress 18,337 — — — — 289,767 — 308,104 Land held for development — — 33,500 — — — 41,075 74,575 Other assets 20,722 10,957 16,337 18,566 49,755 98,191 24,263 238,791 Total assets $ 220,030 $ 133,927 $ 244,986 $ 244,307 $ 407,022 $ 935,762 $ 152,932 $ 2,338,966 Debt $ 166,295 $ 92,131 $ 138,869 $ 102,624 $ 305,223 $ — $ 63,999 $ 869,141 Related party debt — 21,435 — — — — — 21,435 Other liabilities 4,117 6,621 7,548 4,954 9,488 102,982 8,420 144,130 Equity 49,618 13,740 98,569 136,729 92,311 832,780 80,513 1,304,260 Total liabilities and equity $ 220,030 $ 133,927 $ 244,986 $ 244,307 $ 407,022 $ 935,762 $ 152,932 $ 2,338,966 Company's net investment in unconsolidated joint ventures (1) $ 10,425 $ 6,100 $ 14,980 $ 34,107 $ 17,307 $ 177,843 $ 27,694 $ 288,456
Schedule of Condensed Statements of Operations of Equity Method Investments	Condensed Statements of Operations: Year Ended December 31, 2018 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 30,310 $ 13,925 $ 24,729 $ 25,713 $ 71,389 $ 74,309 $ 14,563 $ 254,938 Operating expense (7,947 ) (5,150 ) (7,874 ) (9,496 ) (32,404 ) (20,240 ) (4,373 ) (87,484 ) Interest (6,184 ) (2,713 ) (4,771 ) (4,418 ) (425 ) — (3,403 ) (21,914 ) Related party interest — — — — (13,418 ) — (13,418 ) Depreciation and amortization (7,747 ) (3,577 ) (7,014 ) (5,513 ) (14,285 ) (17,184 ) (2,902 ) (58,222 ) Other income (expense) (16 ) (196 ) (56 ) (68 ) (436 ) (3,982 ) 11,265 6,511 Gain (loss) on sale/impairment — — — (25,389 ) — — — (25,389 ) Net income (loss) $ 8,416 $ 2,289 $ 5,014 $ (19,171 ) $ 10,421 $ 32,903 $ 15,150 $ 55,022 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,540 $ 602 $ 1,752 $ (4,189 ) $ 5,499 $ 7,126 $ 8,052 $ 21,382 Year Ended December 31, 2017 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 31,079 $ 12,976 $ 23,711 $ 25,439 $ 65,372 $ 16,544 $ 11,118 $ 186,239 Operating expense (8,101 ) (4,756 ) (7,989 ) (9,147 ) (26,474 ) (3,417 ) (3,365 ) (63,249 ) Interest (5,801 ) (2,329 ) (5,882 ) (4,065 ) (19,411 ) — (2,807 ) (40,295 ) Depreciation and amortization (7,598 ) (3,238 ) (6,918 ) (5,926 ) (14,485 ) (4,077 ) (2,124 ) (44,366 ) Other income (expense) (100 ) (4 ) (71 ) (65 ) (325 ) (547 ) 15,549 14,437 Gain (loss) on sale/impairment — — — (15,910 ) — 30 — (15,880 ) Net income (loss) $ 9,479 $ 2,649 $ 2,851 $ (9,674 ) $ 4,677 $ 8,533 $ 18,371 $ 36,886 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,914 $ 660 $ 2,118 $ (1,941 ) $ 1,659 $ 1,782 $ 9,963 $ 17,155 Year Ended December 31, 2016 Liberty Kings Hill Unit Liberty Liberty Liberty/ Liberty Property Venture I, LP Trust Illinois, LP Washington, LP Comcast 18th & Arch (2) Other (3) Total Total revenue $ 25,149 $ 11,926 $ 26,599 $ 39,727 $ 65,587 $ — $ 9,888 $ 178,876 Operating expense (6,835 ) (4,854 ) (9,961 ) (15,935 ) (26,761 ) (280 ) (2,801 ) (67,427 ) Interest (4,182 ) (2,554 ) (7,243 ) (10,866 ) (19,737 ) — (2,462 ) (47,044 ) Depreciation and amortization (6,375 ) (3,557 ) (7,589 ) (10,750 ) (14,513 ) — (1,925 ) (44,709 ) Other income (expense) 50 (77 ) 64 257 (213 ) 1,270 7,123 8,474 Gain (loss) on sale/impairment — — 4,068 40,943 — — (11 ) 45,000 Net income (loss) $ 7,807 $ 884 $ 5,938 $ 43,376 $ 4,363 $ 990 $ 9,812 $ 73,170 Company's equity in earnings (loss) of unconsolidated joint ventures $ 2,332 $ 275 $ 2,065 $ 10,857 $ 1,594 $ 213 $ 4,634 $ 21,970 (1) Differences between the Company's net investment in unconsolidated joint ventures and its underlying equity in the net assets of the venture are primarily a result of impairments related to the Company's investment in unconsolidated joint ventures, the deferral of gains associated with the sales of properties to joint ventures in which the Company retains an ownership interest and loans made to the joint ventures by the Company. These adjustments have resulted in an aggregate difference reducing the Company's investments in unconsolidated joint ventures by $65.4 million and $3.0 million as of December 31, 2018 and 2017 , respectively. Differences between historical cost basis and the basis reflected at the joint venture level (other than loans) are typically depreciated over the life of the related asset. (2) Represents the combined results two joint ventures related to the property at 18th and Arch Streets, Philadelphia. (3) Other income/(expense) for this group of joint ventures reflects gains related to the sales of land leasehold interests totaling $11.5 million , $16.0 million and $7.1 million for the years ended December 31, 2018, 2017 and 2016, respectively.

Deferred Financing and Leasin_2

Deferred Financing and Leasing Costs (Tables)	12 Months Ended
	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Schedule of Deferred Financing and Leasing Costs	Deferred financing and leasing costs were comprised of the following as of December 31, 2018 and 2017 (in thousands): December 31, 2018 2017 Deferred financing costs $ 19,598 $ 17,044 Deferred leasing costs 203,609 175,656 Market value intangible 18,071 18,802 Origination value intangible 96,529 90,116 337,807 301,618 Accumulated amortization: Deferred financing costs 13,217 11,002 Deferred leasing costs 84,806 69,118 Market value intangible 14,611 14,324 Origination value intangible 56,434 59,719 169,068 154,163 Deferred financing and leasing costs, net $ 168,739 $ 147,455
Leases, Acquired-in-Place, Market Adjustment
Finite-Lived Intangible Assets [Line Items]
Schedule of Future Amortization Expense	The aggregate amortization of net market value intangible assets and liabilities is a decrease (increase) in rental revenue over the next five years and thereafter as follows (in thousands): 2019 $ (435 ) 2020 (1,224 ) 2021 (1,128 ) 2022 (1,177 ) 2023 (638 ) Thereafter (3,121 ) Total $ (7,723 )
Leases, Acquired-in-Place
Finite-Lived Intangible Assets [Line Items]
Schedule of Future Amortization Expense	The aggregate amortization expense for origination value intangible asset for the next five years and thereafter is as follows (in thousands): 2019 $ 12,345 2020 7,674 2021 6,315 2022 4,063 2023 2,498 Thereafter 7,200 Total $ 40,095

Indebtedness (Tables)

Indebtedness (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Schedule of Debt	The scheduled principal amortization and maturities of the Company's mortgage loans, unsecured notes outstanding and the Credit Facilities (as defined below) and the related weighted average interest rates at December 31, 2018 are as follows (in thousands, except percentages): Weighted Mortgages Average Principal Principal Unsecured Credit Interest Amortization Maturities Notes Facilities Total Rate 2019 $ 6,504 $ 50,043 $ — $ — $ 56,547 4.0 % 2020 3,539 67,361 350,000 — 420,900 4.7 % 2021 2,504 65,009 — 411,846 479,359 3.5 % 2022 2,172 — 400,000 — 402,172 4.1 % 2023 2,281 — 300,000 — 302,281 3.4 % 2024 2,395 — 450,000 — 452,395 4.4 % 2025 2,503 — 400,000 — 402,503 3.8 % 2026 2,494 1,946 400,000 — 404,440 3.3 % 2027 2,617 — — — 2,617 4.8 % 2028 and thereafter 17,183 165,229 — — 182,412 2.9 % Subtotal $ 44,192 $ 349,588 $ 2,300,000 $ 411,846 $ 3,105,626 3.8 % Reconciling items (1) 1,422 — (14,302 ) — (12,880 ) Total for consolidated balance sheet $ 45,614 $ 349,588 $ 2,285,698 $ 411,846 $ 3,092,746 (1) Includes deferred financing costs, premium/discount and market adjustments.

Leasing Activity (Tables)

Leasing Activity (Tables)	12 Months Ended
	Dec. 31, 2018
Operating Leases, Future Minimum Payments Receivable [Abstract]
Schedule of Future Minimum Rental Payments	Future minimum rental payments due from tenants under noncancelable operating leases as of December 31, 2018 are as follows (in thousands): 2019 $ 499,382 2020 449,258 2021 381,385 2022 313,556 2023 244,783 Thereafter 1,059,713 Total $ 2,948,077

Noncontrolling Interest - Ope_2

Noncontrolling Interest - Operating Partnership/Limited Partners' Equity - Preferred Units (Tables)	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest - Operating Partnership / LImited Partners' Equity - Preferred Units [Abstract]
Schedule of Preferred Units	As of December 31, 2018 , the Company had outstanding the following cumulative preferred units of the Operating Partnership: ISSUE AMOUNT UNITS LIQUIDATION PREFERENCE DIVIDEND RATE (in 000’s) Series I-2 $ 7,537 301 $25 6.25 %

Shareholders' Equity - Trust (T

Shareholders' Equity - Trust (Tables)	12 Months Ended
	Dec. 31, 2018
Shareholders' Equity [Abstract]
Schedule of Taxability of Common Shares	The following unaudited table summarizes the taxability of common share distributions (taxability for 2018 is estimated): 2018 2017 2016 Ordinary dividend $ 1.3676 $ 1.5369 $ 1.0319 Qualified dividend — 0.0150 0.0013 Capital gain - 20% 0.0928 0.0482 — IRC Sec 1250 unrecaptured gain - 25% 0.1396 0.0749 0.6176 Return of capital — — 0.2492 Total $ 1.6000 $ 1.6750 $ 1.9000

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Share-based Compensation [Abstract]
Schedule of Stock Options Activity	A summary of the Company's share option activity and related information for the year ended December 31, 2018 follows: Options (000s) Weighted Average Exercise Price Outstanding January 1, 2018 1,581 $ 34.97 Exercised (151 ) 32.83 Outstanding December 31, 2018 1,430 $ 35.20 Exercisable at December 31, 2018 1,430 $ 35.20
Schedule of Key Assumptions Used in the Monte Carlo Simulation	The key assumptions used in the Monte Carlo simulations are as follows: Year Ended December 31, 2018 2017 2016 Risk-free interest rate 2.39% 1.43% 1.01% Volatility 19% 20% 19%
Schedule of Nonvested Share Activity	The Company's restricted LTI share activity for the year ended December 31, 2018 is as follows: Shares (000s) Weighted Avg. Grant Date Fair value Nonvested at January 1, 2018 775 $ 36.43 Granted 343 39.89 Vested (292 ) 36.29 Forfeited (44 ) 37.85 Nonvested at December 31, 2018 782 $ 37.92

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Rental Payments	Future minimum rental payments under the terms of all non-cancelable operating ground leases under which the Company is the lessee, as of December 31, 2018 , were as follows (in thousands): Year Amount 2019 $ 961 2020 961 2021 961 2022 961 2023 961 2024 though 2067 34,194 Total $ 38,999

Quarterly Results of Operatio_2

Quarterly Results of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	A summary of quarterly results of operations for the years ended December 31, 2018 and 2017 follows (in thousands, except for per share data): QUARTER ENDED DEC. 31, SEPT. 30, JUNE 30, MAR. 31, DEC. 31, SEPT. 30, JUNE 30, MAR. 31, 2018 2018 2018 2018 2017 2017 2017 2017 Total revenue $ 180,281 $ 170,389 $ 174,091 $ 180,128 $ 179,825 $ 170,783 $ 160,747 $ 154,029 Income from continuing operations 58,084 49,740 12,942 45,299 109,245 57,770 44,460 37,331 Discontinued operations 115,832 104,332 7,948 98,426 22,579 3,389 8,358 6,913 Net income 173,916 154,072 20,890 143,725 131,824 61,159 52,818 44,244 Income per common share - basic (1) 1.15 1.02 0.13 0.95 0.87 0.41 0.35 0.29 Income per common share - diluted (1) 1.14 1.01 0.13 0.95 0.87 0.40 0.35 0.29 (1) The sum of quarterly financial data may vary from the annual data due to rounding.

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information	The operating information by reportable segment is as follows (in thousands): Year ended December 31, 2018 2017 2016 Operating revenue Carolinas/Richmond $ 79,271 $ 74,158 $ 66,270 Chicago/Minneapolis 67,551 64,706 84,028 Florida 64,486 59,526 99,733 Houston 64,968 59,957 59,582 Lehigh/Central PA 156,629 163,026 141,046 Philadelphia 44,387 45,504 41,838 Southeastern PA 27,874 59,762 91,656 Southern California 30,939 13,856 11,019 United Kingdom 17,193 13,917 13,376 Other 134,553 116,868 125,502 Segment-level operating revenue 687,851 671,280 734,050 Reconciliation to total operating revenues Development service fee income (1) 73,224 82,673 12,941 Discontinued operations (56,056 ) (88,429 ) (71,385 ) Other (130 ) (140 ) (283 ) Total operating revenue $ 704,889 $ 665,384 $ 675,323 Net operating income Carolinas/Richmond $ 57,105 $ 53,132 $ 46,170 Chicago/Minneapolis 40,781 39,231 45,258 Florida 44,204 39,850 62,177 Houston 37,766 32,300 32,499 Lehigh/Central PA 114,201 119,304 102,209 Philadelphia 36,216 35,279 30,862 Southeastern PA 20,044 35,641 53,947 Southern California 24,360 10,199 7,079 United Kingdom 8,996 7,657 6,390 Other 86,638 75,928 82,195 Segment-level net operating income 470,311 448,521 468,786 Reconciliation to income from continuing operations Interest expense (2) (95,442 ) (91,096 ) (115,077 ) Loss on debt extinguishment — (49 ) (27,099 ) Development service fee income 73,224 82,673 12,941 Development service fee expense (134,825 ) (85,805 ) (12,165 ) Depreciation/amortization expense (2) (3) (129,048 ) (132,613 ) (152,556 ) Impairment - real estate assets (2) (39,688 ) (10,632 ) (3,879 ) Gain on property dispositions 81,514 100,387 219,270 Equity in earnings of unconsolidated joint ventures 21,382 17,155 21,970 General and administrative expense (2) (3) (37,278 ) (39,024 ) (40,090 ) Other operating expenses (3) (10,835 ) (5,294 ) (4,418 ) Discontinued operations excluding gain on property dispositions (23,379 ) (26,661 ) (27,129 ) Income taxes (3) (4,701 ) (240 ) 47 Other (4) (5,170 ) (8,516 ) (1,585 ) Income from continuing operations $ 166,065 $ 248,806 $ 339,016 (1) Prior to the fourth quarter of 2016, development service fee income had been classified as other income and development service fee expense had been classified as general and administrative expense. See Note 2. (2) Includes activity in discontinued operations. (3) Excludes costs which are included in determining segment-level net operating income. (4) Includes severance activity in segment-level net operating income.
Schedule of Depreciation and Amortization	The amount of depreciation and amortization expense related to tenant improvement and lease transaction costs within each reporting segment for the net operating income calculation is as follows (in thousands): Year ended December 31, 2018 2017 2016 Carolinas/Richmond $ 5,445 $ 5,205 $ 4,944 Chicago/Minneapolis 4,912 4,393 5,858 Florida 4,050 4,174 6,605 Houston 4,898 5,155 4,713 Lehigh/Central PA 13,121 14,475 12,262 Philadelphia 2,626 2,797 2,706 Southeastern PA 630 3,617 6,134 Southern California 850 612 367 United Kingdom 384 340 259 Other 9,109 8,509 8,687 Depreciation and amortization of tenant improvement and lease transaction costs $ 46,025 $ 49,277 $ 52,535
Schedule of Revenue from External Customers by Products and Services	The Company's operating revenue by product type and by reportable segment for the years ended December 31, 2018 , 2017 and 2016 is as follows (in thousands): Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Industrial Office Total Industrial Office Total Industrial Office Total Carolinas/Richmond $ 79,271 $ — $ 79,271 $ 74,158 $ — $ 74,158 $ 66,270 $ — $ 66,270 Chicago/Minneapolis 63,393 4,158 67,551 60,826 3,880 64,706 65,007 19,021 84,028 Florida 61,878 2,608 64,486 56,923 2,603 59,526 66,028 33,705 99,733 Houston 64,968 — 64,968 58,606 1,351 59,957 58,370 1,212 59,582 Lehigh/Central PA 156,629 — 156,629 163,026 — 163,026 138,766 2,280 141,046 Philadelphia 11,923 32,464 44,387 11,914 33,590 45,504 12,842 28,996 41,838 Southeastern PA 4,139 23,735 27,874 8,925 50,837 59,762 19,448 72,208 91,656 Southern California 30,939 — 30,939 13,856 — 13,856 11,019 — 11,019 United Kingdom 13,601 3,592 17,193 10,369 3,548 13,917 10,775 2,601 13,376 Other 105,622 28,931 134,553 88,601 28,267 116,868 80,743 44,759 125,502 $ 592,363 $ 95,488 687,851 $ 547,204 $ 124,076 671,280 $ 529,268 $ 204,782 734,050 Reconciliation to total operating revenue Development service fee income 73,224 82,673 12,941 Discontinued operations (56,056 ) (88,429 ) (71,385 ) Corporate other (130 ) (140 ) (283 ) Total operating revenue $ 704,889 $ 665,384 $ 675,323
Reconciliation of Assets from Segment to Consolidated	The Company's total assets by reportable segment as of December 31, 2018 and 2017 is as follows (in thousands): As of December 31, 2018 2017 Carolinas/Richmond $ 525,041 $ 543,922 Chicago/Minneapolis 591,792 615,186 Florida 547,232 533,861 Houston 568,756 498,584 Lehigh/Central PA 1,210,220 1,210,746 Philadelphia 624,373 665,843 Southeastern PA 48,827 241,128 Southern California 660,688 362,122 United Kingdom 463,162 251,824 Other 1,497,629 1,445,531 Segment-level total assets 6,737,720 6,368,747 Corporate Other 196,674 71,010 Total assets $ 6,934,394 $ 6,439,757
Schedule of Long-Lived Assets, by Geographical Areas	The Company's real estate assets by reportable segment as of December 31, 2018 and 2017 is as follows (in thousands): As of December 31, 2018 2017 Carolinas/Richmond $ 495,149 $ 491,916 Chicago/Minneapolis 545,919 557,782 Florida 492,797 483,355 Houston 509,100 456,675 Lehigh/Central PA 1,151,148 1,121,115 Philadelphia 286,568 279,338 Southeastern PA 15,467 19,357 Southern California 633,450 343,520 United Kingdom 347,886 191,552 Other 1,228,447 1,004,667 Total real estate assets $ 5,705,931 $ 4,949,277
Schedule of Expenditures on Long-Lived Assets	The Company incurred the following costs related to its long-lived assets for the years ended December 31, 2018 , 2017 and 2016 (in thousands): Year Ended December 31, 2018 2017 2016 Costs incurred on long-lived assets Carolinas/Richmond $ 22,220 $ 31,958 $ 51,647 Chicago/Minneapolis 3,326 14,246 29,317 Florida 41,967 23,832 38,312 Houston 77,323 17,522 25,831 Lehigh/Central PA 63,926 89,304 176,386 Philadelphia 3,326 30,685 57,691 Southeastern PA 5,118 9,737 4,824 Southern California 298,580 183,842 5,599 United Kingdom 165,276 10,501 11,492 Other 240,476 220,411 101,901 Total costs incurred on long-lived assets $ 921,538 $ 632,038 $ 503,000

Accounting for the Impairment_2

Accounting for the Impairment or Disposal of Long-Lived Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting for the Impairment or Disposal of Long-Lived Assets [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations	Information on the operating properties the Company sold during the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Carolinas/Richmond 1 1.5 80,000 $ 7,094 Chicago/Minneapolis — 8.3 — 2,714 Lehigh/Central PA — 66.2 — 9,700 Philadelphia 1 3.1 207,779 130,818 Southeastern PA 32 — 2,325,039 402,708 United Kingdom — — — 65,334 (1) Other 5 — 805,746 255,000 Total 39 79.1 3,418,564 $ 873,368 (1) The Company sold development rights in Horsham, UK. 2017 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 3 — 136,110 $ 8,917 Florida — 16.4 — 13,256 Houston 1 42.2 206,808 36,145 Lehigh/Central PA 2 44.3 1,683,876 249,045 Southeastern PA 4 3.0 313,410 56,156 Other — 7.2 — 3,739 Total 10 113.1 2,340,204 $ 367,258 2016 Sales Reportable Segment Number of Buildings Acres of Developable Land (unaudited) Leaseable Square Feet (unaudited) Gross Proceeds (in thousands) Chicago/Minneapolis 24 5.3 2,037,275 $ 199,825 Florida 51 12.1 3,509,641 505,828 Lehigh/Central PA 1 — 120,777 11,200 Philadelphia — 1.0 — 2,640 Southeastern PA 31 — 2,165,002 266,821 Other 18 18.0 1,631,295 224,241 Total 125 36.4 9,463,990 $ 1,210,555 The following table illustrates the number of sold or held-for-sale properties included in, or excluded from, discontinued operations in this report: Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Total Properties included in discontinued operations 10 37 2 49 Properties included in continuing operations 1 2 8 11 Properties sold or classified as held for sale 11 39 10 60 The following table illustrates the number of sold or held-for-sale properties included in discontinued operations by reportable segment: Reportable Segment Held for Sale as of December 31, 2018 Sold during the year ended December 31, 2018 Sold during the year ended December 31, 2017 Florida 3 — — Houston — — 1 Southeastern PA 5 32 1 Other 2 5 — Total 10 37 2 The following table illustrates aggregate balance sheet information for all held-for-sale properties (in thousands): December 31, 2018 December 31, 2017 Included in Continuing Operations Included in Discontinued Operations Total Included in Continuing Operations Included in Discontinued Operations Total Land and land improvements $ 1,301 $ 92,889 $ 94,190 $ 3,476 $ 155,974 $ 159,450 Buildings and improvements 5,638 126,001 131,639 80,738 493,615 574,353 Development in progress — — — — 45,035 45,035 Land held for development 26,253 — 26,253 863 — 863 Accumulated depreciation (1,546 ) (36,569 ) (38,115 ) (11,785 ) (187,335 ) (199,120 ) Deferred financing and leasing costs, net 58 2,781 2,839 2,210 15,296 17,506 Other assets 164 3,575 3,739 5,137 19,351 24,488 Assets held for sale $ 31,868 $ 188,677 $ 220,545 $ 80,639 $ 541,936 $ 622,575 Liabilities held for sale $ 141 $ 3,042 $ 3,183 $ 1,153 $ 13,470 $ 14,623 A summary of the results of operations for the properties classified as discontinued operations through the respective disposition dates is as follows (in thousands): For the Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Revenue Rental $ 43,393 $ 61,405 $ 48,343 Operating expense reimbursement 12,663 27,024 23,042 Total Revenue 56,056 88,429 71,385 Expenses Rental property 6,959 17,826 13,783 Real estate taxes 7,354 11,582 6,873 Other operating expense (9 ) (272 ) 110 Interest expense 5,812 6,858 9,950 Depreciation and amortization 5,356 19,190 13,642 Impairment charges - real estate assets 7,257 6,686 — Total Expense 32,729 61,870 44,358 Interest and other income 52 102 104 Gain on property dispositions 303,159 14,578 — Income taxes — — (2 ) Income from discontinued operations 326,538 41,239 27,129 Noncontrolling interest - operating partnership (7,608 ) (965 ) (632 ) Income available to common shareholders $ 318,930 $ 40,274 $ 26,497
Schedule of Significant Sale	A summary of net income (excluding gain on sale) related to this portfolio is as follows (in thousands): Year Ended December 31, 2016 Net income $ 48,609 Noncontrolling interest - operating partnership (1,142 ) Income available to common shareholders $ 47,467
Schedule of Asset Impairment Charges	The impairment losses are for operating properties or land parcels and were in the reportable segments and for the amounts as indicated below (in thousands): Year Ended December 31, Reportable Segment 2018 2017 2016 Florida $ 2,396 $ — $ — Houston — 10,632 — Chicago/Minneapolis 2,456 — 3,879 Philadelphia 26,000 — — Southeastern PA 1,579 — — Other 7,257 — — Total $ 39,688 $ 10,632 $ 3,879

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Gain (Loss) on Derivative Instruments	The following table presents the location in the financial statements of the gains or losses recognized related to the Company’s cash flow hedges for the year ended December 31, 2018 , 2017, and 2016 (in thousands): Year Ended December 31, 2018 December 31, 2017 December 31, 2016 Amount of gain (loss) related to the effective portion recognized in other comprehensive income (loss) $ (3,477 ) $ 176 $ (648 ) Amount of gain (loss) related to the effective portion reclassified to interest expense $ 228 $ (453 ) $ (1,069 ) Amount of gain (loss) related to the ineffective portion recognized in interest expense $ 91 $ 168 $ (48 )
Schedule of Derivative Financial Instruments	The following table presents the fair value of the Company’s derivative financial instruments as well as their classification on the accompanying consolidated balance sheets as of December 31, 2018 and December 31, 2017 (amounts in thousands). Derivatives Fair Value at: Balance Sheet Location December 31, 2018 December 31, 2017 Derivatives designated as hedging instruments: Interest Rate Swaps Other Liabilities $ 677 $ 2,243 Interest Rate Treasury Locks Other Liabilities 3,972 — Total $ 4,649 $ 2,243

Supplemental Disclosure to Co_2

Supplemental Disclosure to Consolidated Statement of Cash Flows (Tables)	12 Months Ended
	Dec. 31, 2018
Supplemental Disclosure to Statements of Cash Flows [Abstract]
Schedule of Supplemental Disclosure to Statements of Cash Flows	The following is a reconciliation of the Company's cash and cash equivalents and restricted cash at the beginning and end of the years ended December 31, 2018 and 2017 (amounts in thousands): 2018 2017 Cash and cash equivalents at beginning of period $ 11,882 $ 43,642 Restricted cash at beginning of period 13,803 12,383 Cash and cash equivalents and restricted cash at beginning of period $ 25,685 $ 56,025 Cash and cash equivalents at end of period $ 84,923 $ 11,882 Restricted cash at end of period 10,899 13,803 Cash and cash equivalents and restricted cash at end of period $ 95,822 $ 25,685 The following are supplemental disclosures to the statements of cash flows for the years ended December 31, 2018 , 2017 and 2016 (amounts in thousands): 2018 2017 2016 Write-off of fully depreciated/amortized property and deferred costs - properties included in continuing operations $ 50,169 $ 24,985 $ 34,399 Write-off of fully depreciated/amortized property and deferred costs - properties included in discontinued operations 247 6,951 7,007 Write-off of depreciated property and deferred costs due to sale/demolition - properties included in continuing operations 20,272 15,760 461,480 Write-off of depreciated property and deferred costs due to sale/demolition - properties included in discontinued operations 143,572 17,335 — Write-off of costs related to early debt extinguishment — — 219 Changes in accrued development capital expenditures - properties included in continuing operations 9,078 14,723 (13,651 ) Changes in accrued development capital expenditures - properties included in discontinued operations (1,880 ) (2,382 ) 2,283 Unrealized (loss) gain on cash flow hedge (3,700 ) 605 410 Capitalized equity-based compensation 972 1,096 1,221 Redemption of noncontrolling interests - common units — 152 132

Organization (Details)

Organization (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Liberty Comcast 1701 JFK Boulevard, LP
Variable Interest Entity [Line Items]
Ownership percentage	20.00%
Variable Interest Entity, Not Primary Beneficiary | Other Investments | Liberty Comcast 1701 JFK Boulevard, LP
Variable Interest Entity [Line Items]
Maximum exposure to loss	$ 75.1	$ 17.3
Liberty Property Limited Partnership
Variable Interest Entity [Line Items]
Ownership interest in operating partnership - Limited Partnership	97.70%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Implementation Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Expensed pursuit costs
Restructuring Cost and Reserve [Line Items]
System implementation costs and severance costs	$ 5,066	$ 1,016
General and administrative expense
Restructuring Cost and Reserve [Line Items]
System implementation costs and severance costs	$ 1,011	$ 4,001

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Concentration of Credit Risk) (Details)	12 Months Ended
	Dec. 31, 2018customer
Concentration Risk [Line Items]
Number of customers (in customers)	1,084
Sales Revenue, Net | Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk	10.00%
Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Number of customers (in customers)	0
Concentration risk	4.30%
Sears Holding Corporation | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk	0.80%

Summary of Significant Accoun_6

Summary of Significant Accounting Policies (Real Estate and Depreciation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Construction related payables	$ 48.1	$ 49.3
Building and Building Improvements
Property, Plant and Equipment [Line Items]
Useful life	40 years
Construction in Progress
Property, Plant and Equipment [Line Items]
Compensation costs, capitalized	$ 7.1	$ 5.5	$ 7.2
Minimum | Other Capitalized Property Plant and Equipment
Property, Plant and Equipment [Line Items]
Useful life	15 years
Minimum | Machinery and Equipment
Property, Plant and Equipment [Line Items]
Useful life	5 years
Maximum | Other Capitalized Property Plant and Equipment
Property, Plant and Equipment [Line Items]
Useful life	20 years
Maximum | Machinery and Equipment
Property, Plant and Equipment [Line Items]
Useful life	10 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies (Investments in Unconsolidated Joint Ventures Valuation) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Impairment losses	$ 0	$ 0	$ 0

Summary of Significant Accoun_8

Summary of Significant Accounting Policies (Accounts Receivable/Deferred Rent Receivable) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Allowance for doubtful accounts receivable	$ 6.4	$ 6.6
Provision for doubtful accounts	$ 1.4	$ 0.6	$ 0.6

Summary of Significant Accoun_9

Summary of Significant Accounting Policies (Revenue Recognition) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Development service fee expense		$ 134,825	$ 85,805	$ 12,165
Remaining performance obligation		37,100
Previously Reported | Other income
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Development service fee income	$ 3,789
Previously Reported | General and administrative expense
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Development service fee expense	$ 3,210
Land sold to homebuilders
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues		$ 2,400	$ 300	$ 2,600

Summary of Significant Accou_10

Summary of Significant Accounting Policies (Deferred Financing and Leasing Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Capitalized compensation, leasing costs	$ 2.7	$ 3.6	$ 3.8

Summary of Significant Accou_11

Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Carrying Value | Secured Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument	$ 395,202	$ 267,093
Carrying Value | Unsecured Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument	2,285,698	2,283,513
Fair Value | Secured Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument	397,167	267,298
Fair Value | Unsecured Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument	$ 2,295,699	$ 2,359,998

Summary of Significant Accou_12

Summary of Significant Accounting Policies (Income Taxes) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Percent distribution of REIT taxable income	100.00%
Income provision	$ 0
Number of years subsequent to a failed REIT Qualifying Test the Company would not be Qualified as a REIT	4 years
Uncertain tax positions	$ 0
Penalties and interest	0	$ 0	$ 0
Penalties and interest accrued	0	0
Federal income tax basis	7,100,000,000	$ 6,800,000,000
Taxable REIT Subsidiary
Income Tax Contingency [Line Items]
Operating loss carryforwards	20,800,000
Valuation allowance	$ 20,800,000
Cash | Tax Year 2018 | Tax Cuts and Jobs Act | Taxable REIT Subsidiary
Income Tax Contingency [Line Items]
Effective income tax rate for repatriation of foreign earnings	15.50%
Noncash | Tax Year 2018 | Tax Cuts and Jobs Act | Taxable REIT Subsidiary
Income Tax Contingency [Line Items]
Effective income tax rate for repatriation of foreign earnings	8.00%

Summary of Significant Accou_13

Summary of Significant Accounting Policies (Recently Issued Accounting Standards) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized compensation, leasing costs	$ 2.7	$ 3.6	$ 3.8
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized compensation, leasing costs	$ 1
ASU 2016-02 | Forecast | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right of use asset				$ 18
Operating lease liability				18
ASU 2016-02 | Forecast | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right of use asset				20
Operating lease liability				$ 20

Income per Common Share of th_3

Income per Common Share of the Trust (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income
Income from continuing operations net of noncontrolling interest									$ 160,677	$ 242,066	$ 330,320
Discontinued operations									318,930	40,274	26,497
Income available to common shareholders									$ 479,607	$ 282,340	$ 356,817
Weighted Average Shares
Income from continuing operations net of noncontrolling interest - basic (shares)									147,275	146,742	146,204
Dilutive shares/units for long-term compensation plans (shares)									946	799	685
Income from continuing operations net of noncontrolling interest - diluted (shares)									148,221	147,541	146,889
Per Share/Unit
Income from continuing operations net of noncontrolling interest - basic (USD per share/unit)									$ 1.09	$ 1.65	$ 2.26
Discontinued operations net of noncontrolling interest - basic (USD per share/unit)									2.17	0.27	0.18
Net income available to common shareholders - basic (USD per share/unit)	$ 1.15	$ 1.02	$ 0.13	$ 0.95	$ 0.87	$ 0.41	$ 0.35	$ 0.29	3.26	1.92	2.44
Per Share
Income from continuing operations net of noncontrolling interest - diluted (USD per share/unit)									1.09	1.64	2.25
Discontinued operations net of noncontrolling interest - diluted (USD per share/unit)									2.15	0.27	0.18
Income per common share - diluted (USD per share/unit)	$ 1.14	$ 1.01	$ 0.13	$ 0.95	$ 0.87	$ 0.40	$ 0.35	$ 0.29	$ 3.24	$ 1.91	$ 2.43

Income per Common Share of th_4

Income per Common Share of the Trust (Anti-Dilutive) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Option
Antidilutive Options Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive options that were excluded from the computation of diluted income per common share (in shares)	0	0	800,000

Income per Common Share of th_5

Income per Common Share of the Trust (Exercise of Options) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of option exercises in period (in shares)	151,000	193,000	369,000

Income per Common Share of th_6

Income per Common Share of the Trust (Units and Distributions) (Details) - Common shares - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Redemption of noncontrolling interests – common units (shares)	0	9,826	9,044
Distributions per common share (USD per share)	$ 1.6	$ 1.6	$ 1.90

Income per Common Unit of the_3

Income per Common Unit of the Operating Partnership (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income
Income from continuing operations net of noncontrolling interest									$ 160,677	$ 242,066	$ 330,320
Discontinued operations									318,930	40,274	26,497
Discontinued operations	$ 115,832	$ 104,332	$ 7,948	$ 98,426	$ 22,579	$ 3,389	$ 8,358	$ 6,913	326,538	41,239	27,129
Income available to common shareholders									$ 479,607	$ 282,340	$ 356,817
Weighted Average Shares
Income from continuing operations net of noncontrolling interest - basic (shares)									147,275	146,742	146,204
Dilutive shares/units for long-term compensation plans (shares)									946	799	685
Income from continuing operations net of noncontrolling interest - diluted (shares)									148,221	147,541	146,889
Per Share/Unit
Income from continuing operations net of noncontrolling interest - basic (USD per share/unit)									$ 1.09	$ 1.65	$ 2.26
Discontinued operations net of noncontrolling interest - basic (USD per share/unit)									2.17	0.27	0.18
Net income available to common shareholders - basic (USD per share/unit)	$ 1.15	$ 1.02	$ 0.13	$ 0.95	$ 0.87	$ 0.41	$ 0.35	$ 0.29	3.26	1.92	2.44
Per Share
Income from continuing operations net of noncontrolling interest - diluted (USD per share/unit)									1.09	1.64	2.25
Discontinued operations net of noncontrolling interest - diluted (USD per share/unit)									2.15	0.27	0.18
Income per common share - diluted (USD per share/unit)	$ 1.14	$ 1.01	$ 0.13	$ 0.95	$ 0.87	$ 0.40	$ 0.35	$ 0.29	$ 3.24	$ 1.91	$ 2.43
Liberty Property Limited Partnership
Income
Income from continuing operations net of noncontrolling interest									$ 164,955	$ 248,325	$ 338,758
Less: Preferred unit distributions									(472)	(472)	(472)
Income from continuing operations available to common unitholders									164,483	247,853	338,286
Discontinued operations									326,538	41,239
Discontinued operations									326,538	41,239	27,129
Income available to common shareholders									$ 491,021	$ 289,092	$ 365,415
Weighted Average Shares
Income from continuing operations net of noncontrolling interest - basic (shares)									150,795	150,270	149,740
Dilutive shares/units for long-term compensation plans (shares)									946	799	685
Income from continuing operations net of noncontrolling interest - diluted (shares)									151,741	151,069	150,425
Per Share/Unit
Income from continuing operations net of noncontrolling interest - basic (USD per share/unit)									$ 1.09	$ 1.65	$ 2.26
Discontinued operations net of noncontrolling interest - basic (USD per share/unit)									2.17	0.27	0.18
Net income available to common shareholders - basic (USD per share/unit)									3.26	1.92	2.44
Per Share
Income from continuing operations net of noncontrolling interest - diluted (USD per share/unit)									1.09	1.64	2.25
Discontinued operations net of noncontrolling interest - diluted (USD per share/unit)									2.15	0.27	0.18
Income per common share - diluted (USD per share/unit)									$ 3.24	$ 1.91	$ 2.43

Income per Common Unit of the_4

Income per Common Unit of the Operating Partnership (Anti-Dilutive) (Details) - Stock Option - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Options Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive options that were excluded from the computation of diluted income per common share (in shares)	0	0	800,000
Liberty Property Limited Partnership
Antidilutive Options Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive options that were excluded from the computation of diluted income per common share (in shares)	0	0	800,000

Income per Common Unit of the_5

Income per Common Unit of the Operating Partnership (Exercise of Options) (Details) - Stock Option - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of option exercises in period (in shares)	151,000	193,000	369,000
Liberty Property Limited Partnership | Common units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of option exercises in period (in shares)	151,000	193,000	369,000

Income per Common Unit of the_6

Income per Common Unit of the Operating Partnership (Units and Distributions) (Details) - Liberty Property Limited Partnership - Common units - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Distributions per common share (USD per share)	$ 1.6	$ 1.60	$ 1.90
Limited Partner
Class of Stock [Line Items]
Number of common units converted	0	9,826	9,044

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	$ 3,148,366	$ 3,062,923
Ending Balance	3,396,772	3,148,366
Total accumulated other comprehensive loss included in shareholders' equity	3,329,861	3,087,358
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(38,701)	(56,767)
Other comprehensive income (loss), before reclassifications	(14,161)	18,066
Ending Balance	(52,862)	(38,701)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	150	(455)
Other comprehensive income (loss), before reclassifications	(3,472)	152
Reclassification adjustment	(228)	453
Ending Balance	(3,550)	150
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(38,551)
Ending Balance	(56,412)	(38,551)
AOCI Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	754
Ending Balance	1,169	754
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(37,797)	(56,031)
Ending Balance	(55,243)	(37,797)
Total accumulated other comprehensive loss included in shareholders' equity	$ (55,243)	$ (37,797)

Real Estate (Carrying Value of

Real Estate (Carrying Value of Properties) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate Investment Property, at Cost [Abstract]
Land and Land Improvements	$ 1,256,706	$ 1,023,553
Building and improvements	4,655,784	4,113,163
Total Real Estate	5,912,490	5,136,716
Accumulated Depreciation	974,972	851,624
Depreciation	143,400	148,900	$ 166,800
Industrial Property
Real Estate Investment Property, at Cost [Abstract]
Land and Land Improvements	1,233,655	1,000,810
Building and improvements	4,353,225	3,867,834
Total Real Estate	5,586,880	4,868,644
Accumulated Depreciation	926,703	810,044
Office properties
Real Estate Investment Property, at Cost [Abstract]
Land and Land Improvements	23,051	22,743
Building and improvements	302,559	245,329
Total Real Estate	325,610	268,072
Accumulated Depreciation	$ 48,269	$ 41,580

Real Estate (Real Estate Proper

Real Estate (Real Estate Properties Sold) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)aft²bldg	Dec. 31, 2017USD ($)aft²bldg	Dec. 31, 2016USD ($)aft²bldg	Dec. 31, 2015abldg
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	60
Land and Land Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	30.8
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	39
Leaseable square feet (in sqft) | ft²	3,418,564
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Carolinas/Richmond | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	1
Leaseable square feet (in sqft) | ft²	80,000
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	0
Leaseable square feet (in sqft) | ft²	0
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	0
Leaseable square feet (in sqft) | ft²	0
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	1
Leaseable square feet (in sqft) | ft²	207,779
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	32
Leaseable square feet (in sqft) | ft²	2,325,039
Not Discontinued Operations | 2018 sales | Building and Building Improvements | United Kingdom | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	0
Leaseable square feet (in sqft) | ft²	0
Not Discontinued Operations | 2018 sales | Building and Building Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg	5
Leaseable square feet (in sqft) | ft²	805,746
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	79.1
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Carolinas/Richmond | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	1.5
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	8.3
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	66.2
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	3.1
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	0
Not Discontinued Operations | 2018 sales | Land and Land Improvements | United Kingdom | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	0
Not Discontinued Operations | 2018 sales | Land and Land Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a	0
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	$ 873,368
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Carolinas/Richmond | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	7,094
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	2,714
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	9,700
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	130,818
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	402,708
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | United Kingdom | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	65,334
Not Discontinued Operations | 2018 sales | Land, Buildings and Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $	255,000
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		10
Leaseable square feet (in sqft) | ft²		2,340,204
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		3
Leaseable square feet (in sqft) | ft²		136,110
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		0
Leaseable square feet (in sqft) | ft²		0
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Houston | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		1
Leaseable square feet (in sqft) | ft²		206,808
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		2
Leaseable square feet (in sqft) | ft²		1,683,876
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		4
Leaseable square feet (in sqft) | ft²		313,410
Not Discontinued Operations | 2017 sales | Building and Building Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg		0
Leaseable square feet (in sqft) | ft²		0
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		113.1
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		0
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		16.4
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Houston | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		42.2
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		44.3
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		3
Not Discontinued Operations | 2017 sales | Land and Land Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a		7.2
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		$ 367,258
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		8,917
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		13,256
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Houston | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		36,145
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		249,045
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		56,156
Not Discontinued Operations | 2017 sales | Land, Buildings and Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $		$ 3,739
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			125
Leaseable square feet (in sqft) | ft²			9,463,990
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			24
Leaseable square feet (in sqft) | ft²			2,037,275
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			51
Leaseable square feet (in sqft) | ft²			3,509,641
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			1
Leaseable square feet (in sqft) | ft²			120,777
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			0
Leaseable square feet (in sqft) | ft²			0
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			31
Leaseable square feet (in sqft) | ft²			2,165,002
Not Discontinued Operations | 2016 sales | Building and Building Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg			18
Leaseable square feet (in sqft) | ft²			1,631,295
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			36.4
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			5.3
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			12.1
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			0
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			1
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			0
Not Discontinued Operations | 2016 sales | Land and Land Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a			18
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			$ 1,210,555
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Chicago/Minneapolis | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			199,825
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Florida | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			505,828
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Lehigh/Central PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			11,200
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Philadelphia | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			2,640
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Southeastern PA | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			266,821
Not Discontinued Operations | 2016 sales | Land, Buildings and Improvements | Other | Operating Segments
Disposition Disclosures [Line Items]
Gross proceeds | $			224,241
Not Discontinued Operations | 2015 sales | Building and Building Improvements | Southeastern PA
Disposition Disclosures [Line Items]
Number of buildings (in buildings) | bldg				41
Not Discontinued Operations | 2015 sales | Land and Land Improvements | Southeastern PA
Disposition Disclosures [Line Items]
Acres of developable land (in acres) | a				20
Not Discontinued Operations | 2015 sales | Land, Buildings and Improvements | Southeastern PA
Disposition Disclosures [Line Items]
Gain on sale of property | $			$ 14,300
Recognized deferred gain | $	$ 14,300

Real Estate (Real Estate Prop_2

Real Estate (Real Estate Properties Acquired) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)aft²bldg	Dec. 31, 2017USD ($)aft²bldg	Dec. 31, 2016USD ($)aft²bldg
Business Acquisition [Line Items]
Number of buildings (in buildings)	60
Operating Segments | Land and Land Improvements | Florida
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	30.8
2018 acquisitions | Operating Segments | Building and Building Improvements
Business Acquisition [Line Items]
Number of buildings (in buildings)	16
Leaseable square feet (in sqft) | ft²	4,051,074
2018 acquisitions | Operating Segments | Building and Building Improvements | Florida
Business Acquisition [Line Items]
Number of buildings (in buildings)	0
Leaseable square feet (in sqft) | ft²	0
2018 acquisitions | Operating Segments | Building and Building Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Number of buildings (in buildings)	0
Leaseable square feet (in sqft) | ft²	0
2018 acquisitions | Operating Segments | Building and Building Improvements | Southern California
Business Acquisition [Line Items]
Number of buildings (in buildings)	5
Leaseable square feet (in sqft) | ft²	1,450,041
2018 acquisitions | Operating Segments | Building and Building Improvements | United Kingdom
Business Acquisition [Line Items]
Number of buildings (in buildings)	7
Leaseable square feet (in sqft) | ft²	1,116,421
2018 acquisitions | Operating Segments | Building and Building Improvements | Other
Business Acquisition [Line Items]
Number of buildings (in buildings)	4
Leaseable square feet (in sqft) | ft²	1,484,612
2018 acquisitions | Operating Segments | Land and Land Improvements
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	274.9
2018 acquisitions | Operating Segments | Land and Land Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	170.2
2018 acquisitions | Operating Segments | Land and Land Improvements | Southern California
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	36
2018 acquisitions | Operating Segments | Land and Land Improvements | United Kingdom
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	8.7
2018 acquisitions | Operating Segments | Land and Land Improvements | Other
Business Acquisition [Line Items]
Acres of developable land (in acres) | a	29.2
2018 acquisitions | Operating Segments | Land, Buildings and Improvements
Business Acquisition [Line Items]
Purchase Price | $	$ 632,570
2018 acquisitions | Operating Segments | Land, Buildings and Improvements | Florida
Business Acquisition [Line Items]
Purchase Price | $	15,478
2018 acquisitions | Operating Segments | Land, Buildings and Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Purchase Price | $	34,092
2018 acquisitions | Operating Segments | Land, Buildings and Improvements | Southern California
Business Acquisition [Line Items]
Purchase Price | $	291,916
2018 acquisitions | Operating Segments | Land, Buildings and Improvements | United Kingdom
Business Acquisition [Line Items]
Purchase Price | $	149,582
2018 acquisitions | Operating Segments | Land, Buildings and Improvements | Other
Business Acquisition [Line Items]
Purchase Price | $	$ 141,502
2017 acquisitions | Operating Segments | Building and Building Improvements
Business Acquisition [Line Items]
Number of buildings (in buildings)		8
Leaseable square feet (in sqft) | ft²		1,861,879
2017 acquisitions | Operating Segments | Building and Building Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Number of buildings (in buildings)		0
Leaseable square feet (in sqft) | ft²		0
2017 acquisitions | Operating Segments | Building and Building Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Number of buildings (in buildings)		0
Leaseable square feet (in sqft) | ft²		0
2017 acquisitions | Operating Segments | Building and Building Improvements | Southern California
Business Acquisition [Line Items]
Number of buildings (in buildings)		3
Leaseable square feet (in sqft) | ft²		1,163,233
2017 acquisitions | Operating Segments | Building and Building Improvements | United Kingdom
Business Acquisition [Line Items]
Number of buildings (in buildings)		0
Leaseable square feet (in sqft) | ft²		0
2017 acquisitions | Operating Segments | Building and Building Improvements | Other
Business Acquisition [Line Items]
Number of buildings (in buildings)		5
Leaseable square feet (in sqft) | ft²		698,646
2017 acquisitions | Operating Segments | Land and Land Improvements
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		253.5
2017 acquisitions | Operating Segments | Land and Land Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		10.7
2017 acquisitions | Operating Segments | Land and Land Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		94.6
2017 acquisitions | Operating Segments | Land and Land Improvements | Southern California
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		0
2017 acquisitions | Operating Segments | Land and Land Improvements | United Kingdom
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		34.6
2017 acquisitions | Operating Segments | Land and Land Improvements | Other
Business Acquisition [Line Items]
Acres of developable land (in acres) | a		113.6
2017 acquisitions | Operating Segments | Land, Buildings and Improvements
Business Acquisition [Line Items]
Purchase Price | $		$ 296,398
2017 acquisitions | Operating Segments | Land, Buildings and Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Purchase Price | $		1,242
2017 acquisitions | Operating Segments | Land, Buildings and Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Purchase Price | $		17,798
2017 acquisitions | Operating Segments | Land, Buildings and Improvements | Southern California
Business Acquisition [Line Items]
Purchase Price | $		176,310
2017 acquisitions | Operating Segments | Land, Buildings and Improvements | United Kingdom
Business Acquisition [Line Items]
Purchase Price | $		12,550
2017 acquisitions | Operating Segments | Land, Buildings and Improvements | Other
Business Acquisition [Line Items]
Purchase Price | $		$ 88,498
2016 acquisitions | Operating Segments | Building and Building Improvements
Business Acquisition [Line Items]
Number of buildings (in buildings)			1
Leaseable square feet (in sqft) | ft²			73,160
2016 acquisitions | Operating Segments | Building and Building Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Building and Building Improvements | Chicago/Minneapolis
Business Acquisition [Line Items]
Number of buildings (in buildings)			1
Leaseable square feet (in sqft) | ft²			73,160
2016 acquisitions | Operating Segments | Building and Building Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Building and Building Improvements | Southern California
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Building and Building Improvements | Philadelphia
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Building and Building Improvements | Southeastern PA
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Building and Building Improvements | Other
Business Acquisition [Line Items]
Number of buildings (in buildings)			0
Leaseable square feet (in sqft) | ft²			0
2016 acquisitions | Operating Segments | Land and Land Improvements
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			216.4
2016 acquisitions | Operating Segments | Land and Land Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			12.7
2016 acquisitions | Operating Segments | Land and Land Improvements | Chicago/Minneapolis
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			5.6
2016 acquisitions | Operating Segments | Land and Land Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			76
2016 acquisitions | Operating Segments | Land and Land Improvements | Southern California
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			8.1
2016 acquisitions | Operating Segments | Land and Land Improvements | Philadelphia
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			6.2
2016 acquisitions | Operating Segments | Land and Land Improvements | Southeastern PA
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			8.3
2016 acquisitions | Operating Segments | Land and Land Improvements | Other
Business Acquisition [Line Items]
Acres of developable land (in acres) | a			99.5
2016 acquisitions | Operating Segments | Land, Buildings and Improvements
Business Acquisition [Line Items]
Purchase Price | $			$ 60,892
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Carolinas/Richmond
Business Acquisition [Line Items]
Purchase Price | $			2,251
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Chicago/Minneapolis
Business Acquisition [Line Items]
Purchase Price | $			11,064
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Lehigh/Central PA
Business Acquisition [Line Items]
Purchase Price | $			15,395
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Southern California
Business Acquisition [Line Items]
Purchase Price | $			4,041
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Philadelphia
Business Acquisition [Line Items]
Purchase Price | $			13,943
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Southeastern PA
Business Acquisition [Line Items]
Purchase Price | $			3,344
2016 acquisitions | Operating Segments | Land, Buildings and Improvements | Other
Business Acquisition [Line Items]
Purchase Price | $			$ 10,854

Investments in Unconsolidated_3

Investments in Unconsolidated Joint Ventures (Liberty Venture I, LP) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)ft²bldg	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	60
Gross proceeds	$ 849,528	$ 379,139	$ 1,192,918
Management fee income	$ 73,224	82,673	12,941
New Jersey | Liberty Venture I, LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Leaseable square feet (in sqft) | ft²	4,800
Construction in Progress | New Jersey | Liberty Venture I, LP
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	1
Leaseable square feet (in sqft) | ft²	302
Total anticipated development cost	$ 21,000
Industrial Property | Building and Building Improvements | New Jersey | Liberty Venture I, LP
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	29
Equity Method Investee | Liberty Venture I, LP | New Jersey
Schedule of Equity Method Investments [Line Items]
Management fee income	$ 1,300	1,600	$ 2,300
Prepaid Expenses and Other Current Assets | Equity Method Investee | Liberty Venture I, LP | New Jersey
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ 1	$ 223

Investments in Unconsolidated_4

Investments in Unconsolidated Joint Ventures (Kings Hill Unit Trust) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)ft²bldg	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	60
Management fee income	$ 73,224	$ 82,673	$ 12,941
United Kingdom | Kings Hill Unit Trust
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
United Kingdom | Kings Hill Unit Trust | Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Note receivable interest rate	10.00%
Management fee income	$ 349	302	$ 293
United Kingdom | Building and Building Improvements | Kings Hill Unit Trust
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²	489
United Kingdom | Building and Building Improvements | Office properties | Kings Hill Unit Trust
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	14
Investments in and advances to unconsolidated joint ventures | United Kingdom | Kings Hill Unit Trust | Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Notes receivable	$ 4,900	4,700
Prepaid Expenses and Other Current Assets | United Kingdom | Kings Hill Unit Trust | Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ 15	$ 122

Investments in Unconsolidated_5

Investments in Unconsolidated Joint Ventures (Liberty Illinois, LP) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)aft²bldg	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)ft²bldg
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	60
Management fee income	$ 73,224	$ 82,673	$ 12,941
Joint venture, 2016 sales current quarter | Building and Building Improvements | Liberty Illinois, LP | Not Discontinued Operations
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg			4
Leaseable square feet (in sqft) | ft²			636
Proceeds from sale of property			$ 32,500
Gain (Loss) on Investments | General Partner | Joint venture, 2016 sales current quarter | Building and Building Improvements | Liberty Illinois, LP | Not Discontinued Operations
Schedule of Equity Method Investments [Line Items]
Gains on sale of land and building			1,000
Chicago/Minneapolis | Liberty Illinois, LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Chicago/Minneapolis | Building and Building Improvements | Liberty Illinois, LP
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²	4,900
Chicago/Minneapolis | Building and Building Improvements | Industrial Property | Liberty Illinois, LP
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	12
Chicago/Minneapolis | Land and Land Improvements | Liberty Illinois, LP
Schedule of Equity Method Investments [Line Items]
Acres of developable land (in acres) | a	248
Liberty Illinois, LP | Chicago/Minneapolis | Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Management fee income	$ 900	900	$ 1,000
Prepaid Expenses and Other Current Assets | Liberty Illinois, LP | Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ 331	$ 5

Investments in Unconsolidated_6

Investments in Unconsolidated Joint Ventures (Liberty Washington, LP) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)ft²bldg	Dec. 31, 2017USD ($)bldg	Dec. 31, 2016USD ($)aft²bldg
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	60
Impairment - real estate assets	$ 32,431	$ 3,946	$ 3,879
Gain (loss) on debt extinguishment	0	(49)	(27,099)
Management fee income	$ 73,224	$ 82,673	12,941
Discontinued Operations, Disposed of by Sale
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	37	2
Discontinued operations
Schedule of Equity Method Investments [Line Items]
Impairment - real estate assets	$ 7,257	$ 6,686	$ 0
Northern Virginia and Washington DC | Liberty Washington, LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Building and Building Improvements | Northern Virginia and Washington DC | Liberty Washington, LP
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²	451
Building and Building Improvements | Northern Virginia and Washington DC | Office properties | Liberty Washington, LP
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	2
Joint venture, 2016 sales current quarter | Building and Building Improvements | Liberty Washington, LP | Discontinued Operations, Disposed of by Sale
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg			12
Leaseable square feet (in sqft) | ft²			1,200
Proceeds from sale of property			$ 187,200
Joint venture, 2016 sales current quarter | Land and Land Improvements | Liberty Washington, LP | Discontinued Operations, Disposed of by Sale
Schedule of Equity Method Investments [Line Items]
Acres of developable land (in acres) | a			6
Joint venture, 2016 transfer to lender | Building and Building Improvements | Liberty Washington, LP | Discontinued Operations, Disposed of by Means Other than Sale
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg			6
Leaseable square feet (in sqft) | ft²			698
Mortgages | Joint venture, 2016 transfer to lender | Building and Building Improvements | Liberty Washington, LP | Discontinued Operations, Disposed of by Means Other than Sale
Schedule of Equity Method Investments [Line Items]
Extinguishment of debt			$ 112,500
Equity Method Investee | DC Metro | Liberty Washington, LP
Schedule of Equity Method Investments [Line Items]
Impairment - real estate assets	$ 25,400	15,900
General Partner | Gain (Loss) on Investments | Joint venture, 2016 sales current quarter | Building and Building Improvements | Liberty Washington, LP | Discontinued operations
Schedule of Equity Method Investments [Line Items]
Gains on sale of land and building			6,000
General Partner | Gain (Loss) on Investments | Mortgages | Joint venture, 2016 transfer to lender | Building and Building Improvements | Liberty Washington, LP | Discontinued operations
Schedule of Equity Method Investments [Line Items]
Gain (loss) on debt extinguishment			4,200
Liberty Washington, LP | Equity Method Investee | Northern Virginia and Washington DC
Schedule of Equity Method Investments [Line Items]
Management fee income	1,200	1,100	$ 2,000
Prepaid Expenses and Other Current Assets | Liberty Washington, LP | Equity Method Investee | Northern Virginia and Washington DC
Schedule of Equity Method Investments [Line Items]
Due from related parties	1	316
Investments in and advances to unconsolidated joint ventures | General Partner | Equity Method Investee | DC Metro | Liberty Washington, LP
Schedule of Equity Method Investments [Line Items]
Impairment - real estate assets	$ 6,300	$ 4,000

Investments in Unconsolidated_7

Investments in Unconsolidated Joint Ventures (Liberty/Comcast 1701 JFK Boulevard, LP) (Details) ft² in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2018USD ($)	Dec. 31, 2018USD ($)ft²	Dec. 31, 2017USD ($)ft²	Dec. 31, 2016USD ($)	Jun. 30, 2014
Schedule of Equity Method Investments [Line Items]
Repayments of secured debt		$ 33,561	$ 7,795	$ 29,538
Management fee income		$ 73,224	82,673	12,941
Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage		20.00%
Philadelphia | Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Ownership percentage					20.00%
Philadelphia | Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage		20.00%
Philadelphia | Equity Method Investee | Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Repayments of secured debt	$ 305,200
Due to related parties		$ 60,800
Management fee income		$ 2,800	$ 2,700	$ 2,700
Philadelphia | Building and Building Improvements | Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²		250	1,100
Philadelphia | Building and Building Improvements | Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²		1,260
Philadelphia | Investments in and advances to unconsolidated joint ventures | Equity Method Investee | Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Due to related parties		$ 59	$ 59
Philadelphia | Prepaid Expenses and Other Current Assets | Equity Method Investee | Liberty Comcast 1701 JFK Boulevard, LP
Schedule of Equity Method Investments [Line Items]
Due from related parties		$ 326	$ 272

Investments in Unconsolidated_8

Investments in Unconsolidated Joint Ventures (Liberty Property 18th & Arch LP and Liberty Property 18th & Arch Hotel, LP) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)ft²	Dec. 31, 2017USD ($)ft²	Dec. 31, 2016USD ($)ft²condominium_unit	Jun. 30, 2014USD ($)ft²roomstoryinvestment
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	$ 350,981	$ 288,456
Gain (loss) on sale of properties	384,673	114,965	$ 219,270
Management fee income	73,224	$ 82,673	$ 12,941
Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Maximum exposure to loss	191,400
Philadelphia | Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Number of equity method investments (in investments) | investment				2
Anticipated investment in joint ventures				$ 192,200
Ownership percentage				20.00%
Philadelphia | Construction in Progress | Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Number of stories in a high-rise building (in stories) | story				60
Leaseable square feet (in sqft) | ft²				1,300
Number of hotel rooms (in rooms) | room				217
Total anticipated development cost	$ 225,500			$ 961,200
Philadelphia | Building and Building Improvements | Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²	250	1,100
Total anticipated development cost	$ 136,100	$ 599,600
Liberty Property 18th & Arch
Schedule of Equity Method Investments [Line Items]
Leaseable square feet (in sqft) | ft²			15
Number of residential condominium units (in condominium) | condominium_unit			3
Proceeds from sale of property			$ 14,300
Gain (loss) on sale of properties			300
Liberty Property 18th & Arch | Equity Method Investee | Philadelphia
Schedule of Equity Method Investments [Line Items]
Accrual of development cost guarantee accrual	67,100	5,600
Net operating income (loss)	(61,800)	(3,500)	600
Management fee income	2,200	230	$ 75
Liberty Property 18th & Arch | Equity Method Investee | Prepaid Expenses and Other Current Assets | Philadelphia
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ 1,300	$ 466

Investments in Unconsolidated_9

Investments in Unconsolidated Joint Ventures (Other Joint Ventures) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)aft²bldginvestment	Dec. 31, 2016USD ($)	Dec. 31, 2017USD ($)
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	60
Philadelphia | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
Building and Building Improvements | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Building and Building Improvements | Orlando | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of equity method investments (in investments) | investment	3
Number of buildings (in buildings) | bldg	7
Building and Building Improvements | United Kingdom | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of joint venture		$ 13,700
Loss on sale of join venture		$ 6
Building and Building Improvements | Philadelphia | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of buildings (in buildings) | bldg	1
Leaseable square feet (in sqft) | ft²	48
Purchase price	$ 15,000
Land and Land Improvements | Philadelphia | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Acres of developable land (in acres) | a	1
Investments in and advances to unconsolidated joint ventures | Cambridge Medipark Ltd | Equity Method Investee | United Kingdom | Other Joint Ventures
Schedule of Equity Method Investments [Line Items]
Notes payable	$ 2,400		$ 2,500

Investments in Unconsolidate_10

Investments in Unconsolidated Joint Ventures (Summary Financial Data) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2014investment
Assets
Real estate assets	$ 2,144,692	$ 2,056,711
Accumulated depreciation	(347,849)	(339,215)
Real estate assets, net	1,796,843	1,717,496
Development in progress	200,243	308,104
Land held for development	73,497	74,575
Other assets	292,730	238,791
Total assets	2,363,313	2,338,966
Liabilities and Equity
Debt	570,011	869,141
Related party debt	324,239	21,435
Other liabilities	159,601	144,130
Equity	1,309,462	1,304,260
Total liabilities and equity	2,363,313	2,338,966
Company's net investment in unconsolidated joint ventures	350,981	288,456
Condensed Statements of Operations
Total revenue	254,938	186,239	$ 178,876
Operating expense	(87,484)	(63,249)	(67,427)
Interest	(21,914)	(40,295)	(47,044)
Related party interest	(13,418)
Depreciation and amortization	(58,222)	(44,366)	(44,709)
Other income (expense)	6,511	14,437	8,474
Gain (loss) on sale/impairment	(25,389)	(15,880)	45,000
Net income (loss)	55,022	36,886	73,170
Company's equity in earnings (loss) of unconsolidated joint ventures	21,382	17,155	21,970
Difference between carrying amount and underlying equity	(65,400)	(3,000)
Liberty Venture I, LP
Assets
Real estate assets	251,648	229,600
Accumulated depreciation	(54,373)	(48,629)
Real estate assets, net	197,275	180,971
Development in progress	0	18,337
Land held for development	0	0
Other assets	23,180	20,722
Total assets	220,455	220,030
Liabilities and Equity
Debt	170,743	166,295
Related party debt	0	0
Other liabilities	3,782	4,117
Equity	45,930	49,618
Total liabilities and equity	220,455	220,030
Company's net investment in unconsolidated joint ventures	9,516	10,425
Condensed Statements of Operations
Total revenue	30,310	31,079	25,149
Operating expense	(7,947)	(8,101)	(6,835)
Interest	(6,184)	(5,801)	(4,182)
Related party interest	0
Depreciation and amortization	(7,747)	(7,598)	(6,375)
Other income (expense)	(16)	(100)	50
Gain (loss) on sale/impairment	0	0	0
Net income (loss)	8,416	9,479	7,807
Company's equity in earnings (loss) of unconsolidated joint ventures	2,540	2,914	2,332
Kings Hill Unit Trust
Assets
Real estate assets	144,742	152,998
Accumulated depreciation	(30,554)	(30,028)
Real estate assets, net	114,188	122,970
Development in progress	0	0
Land held for development	0	0
Other assets	12,141	10,957
Total assets	126,329	133,927
Liabilities and Equity
Debt	84,691	92,131
Related party debt	20,239	21,435
Other liabilities	8,537	6,621
Equity	12,862	13,740
Total liabilities and equity	126,329	133,927
Company's net investment in unconsolidated joint ventures	6,230	6,100
Condensed Statements of Operations
Total revenue	13,925	12,976	11,926
Operating expense	(5,150)	(4,756)	(4,854)
Interest	(2,713)	(2,329)	(2,554)
Related party interest	0
Depreciation and amortization	(3,577)	(3,238)	(3,557)
Other income (expense)	(196)	(4)	(77)
Gain (loss) on sale/impairment	0	0	0
Net income (loss)	2,289	2,649	884
Company's equity in earnings (loss) of unconsolidated joint ventures	602	660	275
Liberty Illinois, LP
Assets
Real estate assets	252,751	252,593
Accumulated depreciation	(61,593)	(57,444)
Real estate assets, net	191,158	195,149
Development in progress	0	0
Land held for development	33,769	33,500
Other assets	14,662	16,337
Total assets	239,589	244,986
Liabilities and Equity
Debt	138,964	138,869
Related party debt	0	0
Other liabilities	7,304	7,548
Equity	93,321	98,569
Total liabilities and equity	239,589	244,986
Company's net investment in unconsolidated joint ventures	13,863	14,980
Condensed Statements of Operations
Total revenue	24,729	23,711	26,599
Operating expense	(7,874)	(7,989)	(9,961)
Interest	(4,771)	(5,882)	(7,243)
Related party interest	0
Depreciation and amortization	(7,014)	(6,918)	(7,589)
Other income (expense)	(56)	(71)	64
Gain (loss) on sale/impairment	0	0	4,068
Net income (loss)	5,014	2,851	5,938
Company's equity in earnings (loss) of unconsolidated joint ventures	1,752	2,118	2,065
Liberty Washington, LP
Assets
Real estate assets	210,732	274,847
Accumulated depreciation	(15,009)	(49,106)
Real estate assets, net	195,723	225,741
Development in progress	0	0
Land held for development	0	0
Other assets	17,146	18,566
Total assets	212,869	244,307
Liabilities and Equity
Debt	101,532	102,624
Related party debt	0	0
Other liabilities	3,719	4,954
Equity	107,618	136,729
Total liabilities and equity	212,869	244,307
Company's net investment in unconsolidated joint ventures	27,020	34,107
Condensed Statements of Operations
Total revenue	25,713	25,439	39,727
Operating expense	(9,496)	(9,147)	(15,935)
Interest	(4,418)	(4,065)	(10,866)
Related party interest	0
Depreciation and amortization	(5,513)	(5,926)	(10,750)
Other income (expense)	(68)	(65)	257
Gain (loss) on sale/impairment	(25,389)	(15,910)	40,943
Net income (loss)	(19,171)	(9,674)	43,376
Company's equity in earnings (loss) of unconsolidated joint ventures	(4,189)	(1,941)	10,857
Liberty Comcast 1701 JFK Boulevard, LP
Assets
Real estate assets	497,623	496,210
Accumulated depreciation	(152,169)	(138,943)
Real estate assets, net	345,454	357,267
Development in progress	0	0
Land held for development	0	0
Other assets	43,671	49,755
Total assets	389,125	407,022
Liabilities and Equity
Debt	0	305,223
Related party debt	304,000	0
Other liabilities	8,292	9,488
Equity	76,833	92,311
Total liabilities and equity	389,125	407,022
Company's net investment in unconsolidated joint ventures	75,102	17,307
Condensed Statements of Operations
Total revenue	71,389	65,372	65,587
Operating expense	(32,404)	(26,474)	(26,761)
Interest	(425)	(19,411)	(19,737)
Related party interest	(13,418)
Depreciation and amortization	(14,285)	(14,485)	(14,513)
Other income (expense)	(436)	(325)	(213)
Gain (loss) on sale/impairment	0	0	0
Net income (loss)	10,421	4,677	4,363
Company's equity in earnings (loss) of unconsolidated joint ventures	5,499	1,659	1,594
Liberty Property 18th & Arch
Assets
Real estate assets	688,537	551,874
Accumulated depreciation	(21,160)	(4,070)
Real estate assets, net	667,377	547,804
Development in progress	192,568	289,767
Land held for development	0	0
Other assets	152,845	98,191
Total assets	1,012,790	935,762
Liabilities and Equity
Debt	0	0
Related party debt	0	0
Other liabilities	118,953	102,982
Equity	893,837	832,780
Total liabilities and equity	1,012,790	935,762
Company's net investment in unconsolidated joint ventures	191,430	177,843
Condensed Statements of Operations
Total revenue	74,309	16,544	0
Operating expense	(20,240)	(3,417)	(280)
Interest	0	0	0
Related party interest
Depreciation and amortization	(17,184)	(4,077)	0
Other income (expense)	(3,982)	(547)	1,270
Gain (loss) on sale/impairment	0	30	0
Net income (loss)	32,903	8,533	990
Company's equity in earnings (loss) of unconsolidated joint ventures	7,126	1,782	213
Other Joint Ventures
Assets
Real estate assets	98,659	98,589
Accumulated depreciation	(12,991)	(10,995)
Real estate assets, net	85,668	87,594
Development in progress	7,675	0
Land held for development	39,728	41,075
Other assets	29,085	24,263
Total assets	162,156	152,932
Liabilities and Equity
Debt	74,081	63,999
Related party debt	0	0
Other liabilities	9,014	8,420
Equity	79,061	80,513
Total liabilities and equity	162,156	152,932
Company's net investment in unconsolidated joint ventures	27,820	27,694
Condensed Statements of Operations
Total revenue	14,563	11,118	9,888
Operating expense	(4,373)	(3,365)	(2,801)
Interest	(3,403)	(2,807)	(2,462)
Related party interest	0
Depreciation and amortization	(2,902)	(2,124)	(1,925)
Other income (expense)	11,265	15,549	7,123
Gain (loss) on sale/impairment	0	0	(11)
Net income (loss)	15,150	18,371	9,812
Company's equity in earnings (loss) of unconsolidated joint ventures	8,052	9,963	4,634
Cambridge Medipark Ltd | Leaseholds and Leasehold Improvements
Condensed Statements of Operations
Gain (loss) on sale/impairment	$ 11,500	$ 16,000	$ 7,100
Philadelphia | Liberty Property 18th & Arch
Condensed Statements of Operations
Number of equity method investments (in investments) | investment				2

Deferred Financing and Leasin_3

Deferred Financing and Leasing Costs (Deferred Financing and Leasing Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-lived intangible assets
Deferred financing costs	$ 19,598	$ 17,044
Deferred leasing costs	203,609	175,656
Market value intangible	18,071	18,802
Origination value intangible	96,529	90,116
Finite-lived intangible assets, gross	337,807	301,618
Accumulated amortization:
Deferred financing costs	13,217	11,002
Deferred leasing costs	84,806	69,118
Market value intangible	14,611	14,324
Origination value intangible	56,434	59,719
Finite-lived intangible assets, accumulated amortization	169,068	154,163
Deferred financing and leasing costs, net	168,739	147,455
Amortization of deferred financing costs	3,839	3,750	$ 3,974
Amortization of intangible assets	$ 30,000	$ 31,600	$ 37,100

Deferred Financing and Leasin_4

Deferred Financing and Leasing Costs (Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Unamortized market value intangible liabilities	$ 11,200	$ 9,600
Amortization of above and below Market Leases	$ 45	$ 1,300	$ 1,600
Above Market Leases
Finite-Lived Intangible Assets [Line Items]
Remaining amortization period	2 years 1 month 22 days
Leases, Acquired-in-Place
Finite-Lived Intangible Assets [Line Items]
Remaining amortization period	4 years 1 month 25 days

Deferred Financing and Leasin_5

Deferred Financing and Leasing Costs (Intangible Amortization Schedule) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Deferred financing and leasing costs, net	$ 168,739	$ 147,455
Leases, Acquired-in-Place, Market Adjustment
Acquired Finite-Lived Intangible Assets [Line Items]
2,019	(435)
2,020	(1,224)
2,021	(1,128)
2,022	(1,177)
2,023	(638)
Thereafter	(3,121)
Deferred financing and leasing costs, net	(7,723)
Leases, Acquired-in-Place
Acquired Finite-Lived Intangible Assets [Line Items]
2,019	12,345
2,020	7,674
2,021	6,315
2,022	4,063
2,023	2,498
Thereafter	7,200
Deferred financing and leasing costs, net	$ 40,095

Indebtedness (Overview) (Detail

Indebtedness (Overview) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Weighted average interest rate	3.80%	3.80%	4.30%
Interest costs capitalized	$ 24.5	$ 21	$ 24.1
Cash paid for interest	$ 118.4	$ 111.8	$ 142.7

Indebtedness (Amortization and

Indebtedness (Amortization and Maturity Schedule) (Details) $ in Thousands	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
2,019	$ 56,547
2,020	420,900
2,021	479,359
2,022	402,172
2,023	302,281
2,024	452,395
2,025	402,503
2,026	404,440
2,027	2,617
2028 and thereafter	182,412
Subtotal	3,105,626
Reconciling items	(12,880)
Total for consolidated balance sheet	$ 3,092,746
Weighted average interest rate	3.80%
Principal Amortization, Mortgages
Debt Instrument [Line Items]
2,019	$ 6,504
2,020	3,539
2,021	2,504
2,022	2,172
2,023	2,281
2,024	2,395
2,025	2,503
2,026	2,494
2,027	2,617
2028 and thereafter	17,183
Subtotal	44,192
Reconciling items	1,422
Total for consolidated balance sheet	45,614
Principal Maturities, Mortgages
Debt Instrument [Line Items]
2,019	50,043
2,020	67,361
2,021	65,009
2,022	0
2,023	0
2,024	0
2,025	0
2,026	1,946
2,027	0
2028 and thereafter	165,229
Subtotal	349,588
Reconciling items	0
Total for consolidated balance sheet	349,588
Unsecured Debt
Debt Instrument [Line Items]
2,019	0
2,020	350,000
2,021	0
2,022	400,000
2,023	300,000
2,024	450,000
2,025	400,000
2,026	400,000
2,027	0
2028 and thereafter	0
Subtotal	2,300,000
Reconciling items	(14,302)
Total for consolidated balance sheet	2,285,698
Credit Facilities
Debt Instrument [Line Items]
2,019	0
2,020	0
2,021	411,846
2,022	0
2,023	0
2,024	0
2,025	0
2,026	0
2,027	0
2028 and thereafter	0
Subtotal	411,846
Reconciling items	0
Total for consolidated balance sheet	$ 411,846
Due in Next Twelve Months
Debt Instrument [Line Items]
Weighted average interest rate	4.00%
Due in Year Two
Debt Instrument [Line Items]
Weighted average interest rate	4.70%
Due in Year Three
Debt Instrument [Line Items]
Weighted average interest rate	3.50%
Due in Year Four
Debt Instrument [Line Items]
Weighted average interest rate	4.10%
Due in Year Five
Debt Instrument [Line Items]
Weighted average interest rate	3.40%
Due in Year Six
Debt Instrument [Line Items]
Weighted average interest rate	4.40%
Due in Year Seven
Debt Instrument [Line Items]
Weighted average interest rate	3.80%
Due in Year Eight
Debt Instrument [Line Items]
Weighted average interest rate	3.30%
Due in Year Nine
Debt Instrument [Line Items]
Weighted average interest rate	4.80%
Due After Year Nine
Debt Instrument [Line Items]
Weighted average interest rate	2.90%

Indebtedness (Mortgage Loans an

Indebtedness (Mortgage Loans and Unsecured Notes) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Mortgages
Debt Instrument [Line Items]
Net book value of collateralized real estate properties	$ 478.7
Fixed Rate Debt
Debt Instrument [Line Items]
Percentage bearing fixed interest, amount	2,693.8
Aggregate notional amount	$ 66.8
Fixed Rate Debt | Minimum
Debt Instrument [Line Items]
Effective interest rate	2.60%
Fixed Rate Debt | Maximum
Debt Instrument [Line Items]
Effective interest rate	4.84%
Mortgage Loans and Unsecured Notes
Debt Instrument [Line Items]
Weighted average remaining life	5 years 1 month

Indebtedness (Credit Facilities

Indebtedness (Credit Facilities) (Details)	12 Months Ended
	Dec. 31, 2018USD ($)extension	Dec. 31, 2017USD ($)	Oct. 31, 2017USD ($)
Line of Credit Facility [Line Items]
Amount outstanding	$ 411,846,000	$ 358,939,000
Letter of credit obligations	$ 8,300,000
Credit Facility Group Lenders
Line of Credit Facility [Line Items]
Number of maturity extensions (in extensions) | extension	2
Length of maturity extension	6 months
Competitive bid percentage	50.00%
Total debt to total assets	0.60
Adjusted earnings before interest, taxes, depreciation and amortization to fixed charges, Covenant ratio	1.50
Debt covenant percentage	60.00%
Secured debt to total assets	35.00%
Unencumbered net operating income to unsecured interest expense value for debt covenant	175.00%
Credit Facility Group Lenders | Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 800,000,000
Basis spread on variable rate	0.875%
Commitment fee percentage	0.15%
Amount outstanding	$ 310,000,000
Credit Facility Group Lenders | Commercial Paper
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 100,000,000
Basis spread on variable rate	0.95%
Amount outstanding	$ 100,000,000
Credit Facility Group Lenders | Letter of Credit
Line of Credit Facility [Line Items]
Letter of credit obligations	8,300,000
Working Capital Facility Lender | Credit Facilities
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 30,000,000
Amount outstanding	$ 1,800,000

Indebtedness (Activity) (Detail

Indebtedness (Activity) (Details)	1 Months Ended	12 Months Ended
	Nov. 30, 2016USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jan. 31, 2019USD ($)	Dec. 31, 2018GBP (£)	Oct. 31, 2017USD ($)	Oct. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Debt Instrument [Line Items]
Debt instrument, face amount		$ 3,105,626,000
Loss on debt extinguishment		0	$ 49,000	$ 27,099,000
Senior Notes | 3.25% Senior Notes
Debt Instrument [Line Items]
Debt instrument, face amount									$ 400,000,000
Stated interest rate									3.25%
Senior Notes | 5.5% Senior Note
Debt Instrument [Line Items]
Stated interest rate									5.50%
Repurchased face amount of debt									$ 300,000,000
Senior Notes | 6.625% Senior Note
Debt Instrument [Line Items]
Stated interest rate	6.625%
Repurchased face amount of debt	$ 296,500,000
Unsecured Debt
Debt Instrument [Line Items]
Debt instrument, face amount		$ 2,300,000,000
Medium-term Notes | 7.5% Medium Term Note
Debt Instrument [Line Items]
Stated interest rate	7.50%
Repurchased face amount of debt	$ 100,000,000
Mortgages | Mortgage Loan, 2.64%
Debt Instrument [Line Items]
Debt instrument, face amount | £						£ 129,500,000
Stated interest rate		2.64%				2.64%
Unsecured Debt
Debt Instrument [Line Items]
Loss on debt extinguishment	$ 27,100,000
Revolving Credit Facility | Credit Facility Group Lenders
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 800,000,000
Revolving Credit Facility | Credit Facility Group Lenders | 2014 Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 800,000,000
Revolving Credit Facility | Credit Facility Group Lenders | 2017 Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity								800,000,000
Commercial Paper | Credit Facility Group Lenders
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 100,000,000
Commercial Paper | Credit Facility Group Lenders | 2017 Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity								100,000,000
Credit Facilities | Working Capital Facility Lender
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 30,000,000
Credit Facilities | Working Capital Facility Lender | 2017 Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 30,000,000
Subsequent Event | Senior Notes | 4.375% Senior Unsecured Notes
Debt Instrument [Line Items]
Debt instrument, face amount					$ 350,000,000
Stated interest rate					4.375%

Leasing Activity (Details)

Leasing Activity (Details) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
2,019	$ 499,382
2,020	449,258
2,021	381,385
2,022	313,556
2,023	244,783
Thereafter	1,059,713
Total	$ 2,948,077

Noncontrolling Interest - Ope_3

Noncontrolling Interest - Operating Partnership/Limited Partners' Equity - Preferred Units (Details) - Series I-2 - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Preferred Units [Line Items]
AMOUNT	$ 7,537
UNITS (in shares/units)	301,483
LIQUIDATION PREFERENCE (USD per share)	$ 25
DIVIDEND RATE	6.25%
Preferred distributions	$ 472	$ 472	$ 472

Shareholders' Equity - Trust (D

Shareholders' Equity - Trust (Details)	12 Months Ended
	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Sep. 30, 2017USD ($)	Aug. 31, 2015USD ($)
Common Units
Common units outstanding (in shares) | shares	3,520,205	3,520,205
Units issued in connection with acquisitions (in shares) | shares	0	0	0
Continuous Equity Offering
Maximum equity capacity	$ 200,000,000
Equity available	$ 125,000,000
Shares issued during period under continuous equity offerings, shares, new issues (in shares) | shares	0	0	0
Share Repurchase
Share repurchase, value			$ 40,896,000
Common units
Common Shares
Common units distributions	$ 241,800,000	$ 252,300,000	$ 285,900,000
Ordinary dividend (USD per share) | $ / shares	$ 1.3676	$ 1.5369	$ 1.0319
Qualified dividend (USD per share) | $ / shares	0	0.0150	0.0013
Capital gain - 20% (USD per share) | $ / shares	0.0928	0.0482	0
IRC Sec 1250 unrecaptured gain - 25% (USD per share) | $ / shares	0.1396	0.0749	0.6176
Return of capital (USD per share) | $ / shares	0	0	0.2492
Total (USD per share) | $ / shares	$ 1.6	$ 1.675	$ 1.9
Common shares
Dividend Reinvestment and Share Purchase Plan
Dividend reinvestment plan (in shares) | shares	36,807	42,366	56,426
Share Repurchase
Stock repurchase program, authorized amount				$ 250,000,000
Share repurchase (in shares) | shares	0		1,396,844
Share repurchase, value			$ 40,900,000
Liberty Property Limited Partnership
Common Units
Common units outstanding (in shares) | shares	3,520,205	3,520,205
Closing price of the common shares	$ 147,400,000
Units issued in connection with acquisitions (in shares) | shares	0	0	0
Share Repurchase
Share repurchase, value			$ 40,896,000
Liberty Property Limited Partnership | Common units
Dividend Reinvestment and Share Purchase Plan
Dividend reinvestment plan (in shares) | shares	36,807	42,366	56,426
Share Repurchase
Stock repurchase program, authorized amount					$ 250,000,000
Share repurchase (in shares) | shares		0	1,400,000
Share repurchase, value			$ 40,900,000
Conversion Ratio of Common Units to Common Shares
Common Units
Common unit, convertible to common stock	1
Common stock, converted from common unit	1

Owners' Equity - Operating Pa_2

Owners' Equity - Operating Partnership (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Aug. 31, 2015
Common Shares
Common units outstanding (in shares)	3,520,205	3,520,205
Units issued in connection with acquisitions (in shares)	0	0	0
Share Repurchase
Share repurchase, value			$ 40,896,000
Liberty Property Limited Partnership
Common Shares
Common units outstanding (in shares)	3,520,205	3,520,205
Closing price of the common shares	$ 147,400,000
Units issued in connection with acquisitions (in shares)	0	0	0
Share Repurchase
Share repurchase, value			$ 40,896,000
Liberty Property Limited Partnership | Common units
Dividend Reinvestment and Share Purchase Plan
Dividend reinvestment plan (in shares)	36,807	42,366	56,426
Share Repurchase
Stock repurchase program, authorized amount				$ 250,000,000
Share repurchase (in shares)		0	1,400,000
Share repurchase, value			$ 40,900,000

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - Pension Plan - 401(k) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure [Line Items]
Company match for defined contribution plan percentage	3.00%
Cost recognized	$ 784	$ 755	$ 874

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	21,100,000
Compensation cost capitalized	$ 1,000,000	$ 1,100,000	$ 1,200,000
Bonus Shares and Plans
Common shares reserved for future issuance	4,653,912	5,049,687	5,264,285
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	750,000
Share-based compensation expense	$ 87,502	$ 80,000	$ 122,000
Bonus Shares and Plans
Maximum percent of salary contributed	10.00%
Discount on market value of shares	15.00%
Shares issued	7,475	10,410	11,022
Stock Options | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option term	10 years
Vesting period	3 years
Share-based compensation expense	$ 12,000	$ 73,000	$ 165,000
Weighted average fair value of options granted (USD per share)	$ 0		$ 0
Options granted in period (in shares)	0
Exercise price for options outstanding lower limit (USD per share)	$ 20.32
Exercise price for options outstanding upper limit (USD per share)	$ 39.59
Weighted average remaining contractual life of options exercisable	4 years
Weighted average remaining contractual life of options outstanding	4 years 8 days
Total intrinsic value of options exercised	$ 1,400,000	1,400,000	$ 3,500,000
Number of options outstanding and exercisable that had an exercise price lower than the Company's share price	1,400,000
Aggregate intrinsic value of options	$ 9,600,000
Total cash received from the exercise of options	5,000,000	6,700,000	14,400,000
Unrecognized compensation costs related to nonvested options	$ 0
Stock Options | First Portion | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	20.00%
Stock Options | Second Portion | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	50.00%
Stock Options | Third Portion | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	100.00%
Restricted Stock | Long Term Incentive Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 11,100,000	$ 11,300,000	$ 12,200,000
Shares granted	343,000
Compensation costs not yet recognized, period for recognition	1 year 1 month 27 days
Long Term Incentive Shares
Granted (USD per share)	$ 39.89	$ 39.93	$ 32.48
Total unrecognized compensation cost related to nonvested shares	$ 8,400,000
Total fair value of restricted shares vested	$ 10,600,000	$ 11,700,000	$ 9,000,000
Restricted Stock | Long Term Incentive Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock | Long Term Incentive Shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Restricted Stock Units (RSUs) | First Portion | 2008 plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Bonus Shares | Bonus Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1,700,000	$ 2,000,000	$ 4,700,000
Shares granted	41,620	51,416	140,376
Bonus Shares | Bonus Shares | Minimum
Bonus Shares and Plans
Percent of bonuses taken in cash	100.00%
Bonus Shares | Bonus Shares | Maximum
Bonus Shares and Plans
Percent of bonuses taken in cash	120.00%
Salaries, Wages and Officers' Compensation	$ 50,000
Performance Shares | Profit Sharing Plan
Bonus Shares and Plans
Maximum percent of salary contributed	5.00%
Profit sharing plan expense	$ 706,000	$ 730,000	$ 669,000
Chief Executive Officer | Restricted Stock Units (RSUs) | 2008 plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Chief Executive Officer | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	250.00%
Chief Executive Officer | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	272.00%
Chief Executive Officer | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	272.00%
Chief Executive Officer | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2018 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation	149.00%
Chief Executive Officer | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2017 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation		132.00%
Chief Executive Officer | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2016 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation			174.00%
Executives Other | Restricted Stock Units (RSUs) | 2008 plan | 2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Executives Other | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	200.00%
Executives Other | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	200.00%
Executives Other | Restricted Stock Units (RSUs) | 2008 plan | Maximum | 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	200.00%
Executives Other | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2018 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation	125.00%
Executives Other | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2017 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation		105.00%
Executives Other | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2016 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation			136.00%
Chief Financial Officer | Restricted Stock Units (RSUs) | First Portion | 2008 plan | 2016 Grant
Long Term Incentive Shares
Monte Carlo RSU Valuation	160.00%
Chief Financial Officer | Restricted Stock Units (RSUs) | First Portion | 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Chief Financial Officer | Restricted Stock Units (RSUs) | Second Portion | 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Chief Financial Officer | Restricted Stock Units (RSUs) | Second Portion | 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years

Share-Based Compensation (Optio

Share-Based Compensation (Option Rollforward) (Details) - Options - Stock Options - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of options granted (USD per share)	$ 0	$ 0
Options
Outstanding, Beginning Balance (in shares)	1,581
Exercised (in shares)	(151)
Outstanding, Ending Balance (in shares)	1,430
Exercisable, period-end (in shares)	1,430
Weighted Average Exercise Price
Outstanding, Beginning Balance (USD per share)	$ 34.97
Exercised (USD per share)	32.83
Outstanding, Ending Balance (USD per share)	35.20
Exercisable, period-end (USD per share)	$ 35.20

Share-Based Compensation (Valua

Share-Based Compensation (Valuation Assumptions) (Details) - First Portion - 2008 plan - Restricted Stock Units (RSUs)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	2.39%
Historical volatility factor	19.00%
2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.43%
Historical volatility factor		20.00%
2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate			1.01%
Historical volatility factor			19.00%

Share-Based Compensation (LTI S

Share-Based Compensation (LTI Share Activity) (Details) - Long Term Incentive Shares - Restricted Stock - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Shares
Nonvested, Beginning Balance (shares)	775
Granted (shares)	343
Vested (shares)	(292)
Forfeited (shares)	(44)
Nonvested, Ending Balance (shares)	782	775
Weighted Avg. Grant Date Fair value
Nonvested, Beginning Balance (USD per share)	$ 36.43
Granted (USD per share)	39.89	$ 39.93	$ 32.48
Vested (USD per share)	36.29
Forfeited (USD per share)	37.85
Nonvested, Ending Balance (USD per share)	$ 37.92	$ 36.43

Commitments and Contingencies_2

Commitments and Contingencies (Future Minimum Rental Payments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
2,019	$ 961
2,020	961
2,021	961
2,022	961
2,023	961
2024 though 2067	34,194
Total	38,999
Other Expenses
Operating ground lease expense	$ 1,500	$ 100	$ 1,000

Commitments and Contingencies_3

Commitments and Contingencies (Legal Matters) (Details)	Dec. 31, 2018claim
Loss Contingency, Information about Litigation Matters [Abstract]
Number of legal proceedings (in claims)	0

Commitments and Contingencies_4

Commitments and Contingencies (Other) (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)ft²bldg	Dec. 31, 2017USD ($)ft²	Dec. 31, 2016USD ($)	Jun. 30, 2014USD ($)ft²investment
Supply Commitment [Line Items]
Letter of credit obligations	$ 8,300
Number of buildings (in buildings) | bldg	60
Development in progress	$ 472,169	$ 333,437
Deferred leasing costs in development	203,609	175,656
Costs incurred to date	134,825	$ 85,805	$ 12,165
Land, Buildings and Improvements | Supply Commitment
Supply Commitment [Line Items]
Remaining amount committed or obligated to pay	$ 13,000
Construction in Progress | Supply Commitment
Supply Commitment [Line Items]
Number of buildings (in buildings) | bldg	29
Leaseable square feet (in sqft) | ft²	8,200
Total anticipated development cost	$ 735,000
Deferred leasing costs in development	$ 13,200
Construction in Progress | Equity Method Investments | Supply Commitment
Supply Commitment [Line Items]
Number of buildings (in buildings) | bldg	2
Total anticipated development cost	$ 235,800
Leasehold Improvements | Supply Commitment
Supply Commitment [Line Items]
Remaining maximum amount committed for tenant improvements	17,800
American Water Works, Inc | Building and Building Improvements
Supply Commitment [Line Items]
Costs incurred to date	159,200
American Water Works, Inc | Building and Building Improvements | Supply Commitment
Supply Commitment [Line Items]
Fee development commitment	$ 170,900
Liberty Property 18th & Arch | Philadelphia
Supply Commitment [Line Items]
Number of equity method investments (in investments) | investment				2
Liberty Property 18th & Arch | Philadelphia | Building and Building Improvements
Supply Commitment [Line Items]
Leaseable square feet (in sqft) | ft²	250	1,100
Total anticipated development cost	$ 136,100	$ 599,600
Liberty Property 18th & Arch | Philadelphia | Construction in Progress
Supply Commitment [Line Items]
Leaseable square feet (in sqft) | ft²				1,300
Total anticipated development cost	$ 225,500			$ 961,200
Other Joint Ventures | Philadelphia | Building and Building Improvements
Supply Commitment [Line Items]
Number of buildings (in buildings) | bldg	1
Leaseable square feet (in sqft) | ft²	48
Other Liabilities | Guarantee Obligations | Liberty Property 18th & Arch | Philadelphia
Supply Commitment [Line Items]
Loss contingency accrual	$ 67,300	$ 5,600

Commitments and Contingencies_5

Commitments and Contingencies (Purchase Commitments) (Details) $ in Millions	Dec. 31, 2018USD ($)
Land Purchases
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Remaining amount committed to future acquisitions	$ 49.5

Quarterly Results of Operatio_3

Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 180,281	$ 170,389	$ 174,091	$ 180,128	$ 179,825	$ 170,783	$ 160,747	$ 154,029	$ 704,889	$ 665,384	$ 675,323
Income from continuing operations	58,084	49,740	12,942	45,299	109,245	57,770	44,460	37,331	166,065	248,806	339,016
Discontinued operations	115,832	104,332	7,948	98,426	22,579	3,389	8,358	6,913	326,538	41,239	27,129
Net income	$ 173,916	$ 154,072	$ 20,890	$ 143,725	$ 131,824	$ 61,159	$ 52,818	$ 44,244	$ 492,603	$ 290,045	$ 366,145
Net income available to common shareholders - basic (USD per share/unit)	$ 1.15	$ 1.02	$ 0.13	$ 0.95	$ 0.87	$ 0.41	$ 0.35	$ 0.29	$ 3.26	$ 1.92	$ 2.44
Income per common share - diluted (USD per share/unit)	$ 1.14	$ 1.01	$ 0.13	$ 0.95	$ 0.87	$ 0.40	$ 0.35	$ 0.29	$ 3.24	$ 1.91	$ 2.43

Segment Information (Performanc

Segment Information (Performance of the Reportable Segments Based on Property Level Operating Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total revenue	$ 180,281	$ 170,389	$ 174,091	$ 180,128	$ 179,825	$ 170,783	$ 160,747	$ 154,029	$ 704,889	$ 665,384	$ 675,323
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense									(89,630)	(84,238)	(105,127)
Loss on debt extinguishment									0	(49)	(27,099)
Development service fee income									73,224	82,673	12,941
Development service fee expense									(134,825)	(85,805)	(12,165)
Depreciation and amortization expense									(169,717)	(162,700)	(191,448)
Impairment - real estate assets									(32,431)	(3,946)	(3,879)
Gain on property dispositions									81,514	100,387	219,270
Equity in earnings of unconsolidated joint ventures									21,382	17,155	21,970
General and administrative expense									(53,843)	(56,191)	(63,071)
Other operating expenses									(1,795)	(5,066)	(1,016)
Income taxes									(7,364)	(1,992)	(1,969)
Income from continuing operations	$ 58,084	$ 49,740	$ 12,942	$ 45,299	$ 109,245	$ 57,770	$ 44,460	$ 37,331	166,065	248,806	339,016
Operating Segments
Segment Reporting Information [Line Items]
Total revenue									687,851	671,280	734,050
Net operating income									470,311	448,521	468,786
Operating Segments | Carolinas/Richmond
Segment Reporting Information [Line Items]
Total revenue									79,271	74,158	66,270
Net operating income									57,105	53,132	46,170
Operating Segments | Chicago/Minneapolis
Segment Reporting Information [Line Items]
Total revenue									67,551	64,706	84,028
Net operating income									40,781	39,231	45,258
Operating Segments | Florida
Segment Reporting Information [Line Items]
Total revenue									64,486	59,526	99,733
Net operating income									44,204	39,850	62,177
Operating Segments | Houston
Segment Reporting Information [Line Items]
Total revenue									64,968	59,957	59,582
Net operating income									37,766	32,300	32,499
Operating Segments | Lehigh/Central PA
Segment Reporting Information [Line Items]
Total revenue									156,629	163,026	141,046
Net operating income									114,201	119,304	102,209
Operating Segments | Philadelphia
Segment Reporting Information [Line Items]
Total revenue									44,387	45,504	41,838
Net operating income									36,216	35,279	30,862
Operating Segments | Southeastern PA
Segment Reporting Information [Line Items]
Total revenue									27,874	59,762	91,656
Net operating income									20,044	35,641	53,947
Operating Segments | Southern California
Segment Reporting Information [Line Items]
Total revenue									30,939	13,856	11,019
Net operating income									24,360	10,199	7,079
Operating Segments | United Kingdom
Segment Reporting Information [Line Items]
Total revenue									17,193	13,917	13,376
Net operating income									8,996	7,657	6,390
Operating Segments | Other
Segment Reporting Information [Line Items]
Total revenue									134,553	116,868	125,502
Net operating income									86,638	75,928	82,195
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total revenue									(130)	(140)	(283)
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense									(95,442)	(91,096)	(115,077)
Loss on debt extinguishment										(49)	(27,099)
Development service fee income									73,224	82,673	12,941
Development service fee expense									(134,825)	(85,805)	(12,165)
Depreciation and amortization expense									(129,048)	(132,613)	(152,556)
Impairment - real estate assets									(39,688)	(10,632)	(3,879)
Gain on property dispositions									81,514	100,387	219,270
Equity in earnings of unconsolidated joint ventures									21,382	17,155	21,970
General and administrative expense									(37,278)	(39,024)	(40,090)
Other operating expenses									(10,835)	(5,294)	(4,418)
Discontinued operations excluding gain on property dispositions									(23,379)	(26,661)	(27,129)
Income taxes									(4,701)	(240)	47
Other									$ (5,170)	$ (8,516)	$ (1,585)

Segment Information (Depreciati

Segment Information (Depreciation and amortization of leasing transaction costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	$ 46,025	$ 49,277	$ 52,535
Carolinas/Richmond
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	5,445	5,205	4,944
Chicago/Minneapolis
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	4,912	4,393	5,858
Florida
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	4,050	4,174	6,605
Houston
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	4,898	5,155	4,713
Lehigh/Central PA
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	13,121	14,475	12,262
Philadelphia
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	2,626	2,797	2,706
Southeastern PA
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	630	3,617	6,134
Southern California
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	850	612	367
United Kingdom
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	384	340	259
Other
Segment Reporting Information [Line Items]
Depreciation and amortization of tenant improvement and lease transaction costs	$ 9,109	$ 8,509	$ 8,687

Segment Information (Operating

Segment Information (Operating Revenues by Segment and Type) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue from External Customer [Line Items]
Total revenue	$ 180,281	$ 170,389	$ 174,091	$ 180,128	$ 179,825	$ 170,783	$ 160,747	$ 154,029	$ 704,889	$ 665,384	$ 675,323
Operating Segments
Revenue from External Customer [Line Items]
Total revenue									687,851	671,280	734,050
Operating Segments | Carolinas/Richmond
Revenue from External Customer [Line Items]
Total revenue									79,271	74,158	66,270
Operating Segments | Chicago/Minneapolis
Revenue from External Customer [Line Items]
Total revenue									67,551	64,706	84,028
Operating Segments | Florida
Revenue from External Customer [Line Items]
Total revenue									64,486	59,526	99,733
Operating Segments | Houston
Revenue from External Customer [Line Items]
Total revenue									64,968	59,957	59,582
Operating Segments | Lehigh/Central PA
Revenue from External Customer [Line Items]
Total revenue									156,629	163,026	141,046
Operating Segments | Philadelphia
Revenue from External Customer [Line Items]
Total revenue									44,387	45,504	41,838
Operating Segments | Southeastern PA
Revenue from External Customer [Line Items]
Total revenue									27,874	59,762	91,656
Operating Segments | Southern California
Revenue from External Customer [Line Items]
Total revenue									30,939	13,856	11,019
Operating Segments | United Kingdom
Revenue from External Customer [Line Items]
Total revenue									17,193	13,917	13,376
Operating Segments | Other
Revenue from External Customer [Line Items]
Total revenue									134,553	116,868	125,502
Segment Reconciling Items | Development service fee income
Revenue from External Customer [Line Items]
Total revenue									73,224	82,673	12,941
Segment Reconciling Items | Discontinued operations
Revenue from External Customer [Line Items]
Total revenue									(56,056)	(88,429)	(71,385)
Corporate, Non-Segment
Revenue from External Customer [Line Items]
Total revenue									(130)	(140)	(283)
Industrial Property | Operating Segments
Revenue from External Customer [Line Items]
Total revenue									592,363	547,204	529,268
Industrial Property | Operating Segments | Carolinas/Richmond
Revenue from External Customer [Line Items]
Total revenue									79,271	74,158	66,270
Industrial Property | Operating Segments | Chicago/Minneapolis
Revenue from External Customer [Line Items]
Total revenue									63,393	60,826	65,007
Industrial Property | Operating Segments | Florida
Revenue from External Customer [Line Items]
Total revenue									61,878	56,923	66,028
Industrial Property | Operating Segments | Houston
Revenue from External Customer [Line Items]
Total revenue									64,968	58,606	58,370
Industrial Property | Operating Segments | Lehigh/Central PA
Revenue from External Customer [Line Items]
Total revenue									156,629	163,026	138,766
Industrial Property | Operating Segments | Philadelphia
Revenue from External Customer [Line Items]
Total revenue									11,923	11,914	12,842
Industrial Property | Operating Segments | Southeastern PA
Revenue from External Customer [Line Items]
Total revenue									4,139	8,925	19,448
Industrial Property | Operating Segments | Southern California
Revenue from External Customer [Line Items]
Total revenue									30,939	13,856	11,019
Industrial Property | Operating Segments | United Kingdom
Revenue from External Customer [Line Items]
Total revenue									13,601	10,369	10,775
Industrial Property | Operating Segments | Other
Revenue from External Customer [Line Items]
Total revenue									105,622	88,601	80,743
Office properties | Operating Segments
Revenue from External Customer [Line Items]
Total revenue									95,488	124,076	204,782
Office properties | Operating Segments | Carolinas/Richmond
Revenue from External Customer [Line Items]
Total revenue									0	0	0
Office properties | Operating Segments | Chicago/Minneapolis
Revenue from External Customer [Line Items]
Total revenue									4,158	3,880	19,021
Office properties | Operating Segments | Florida
Revenue from External Customer [Line Items]
Total revenue									2,608	2,603	33,705
Office properties | Operating Segments | Houston
Revenue from External Customer [Line Items]
Total revenue									0	1,351	1,212
Office properties | Operating Segments | Lehigh/Central PA
Revenue from External Customer [Line Items]
Total revenue									0	0	2,280
Office properties | Operating Segments | Philadelphia
Revenue from External Customer [Line Items]
Total revenue									32,464	33,590	28,996
Office properties | Operating Segments | Southeastern PA
Revenue from External Customer [Line Items]
Total revenue									23,735	50,837	72,208
Office properties | Operating Segments | Southern California
Revenue from External Customer [Line Items]
Total revenue									0	0	0
Office properties | Operating Segments | United Kingdom
Revenue from External Customer [Line Items]
Total revenue									3,592	3,548	2,601
Office properties | Operating Segments | Other
Revenue from External Customer [Line Items]
Total revenue									$ 28,931	$ 28,267	$ 44,759

Segment Information (Total Asse

Segment Information (Total Assets by Segment) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Assets	$ 6,934,394	$ 6,439,757
Operating Segments
Segment Reporting Information [Line Items]
Assets	6,737,720	6,368,747
Operating Segments | Carolinas/Richmond
Segment Reporting Information [Line Items]
Assets	525,041	543,922
Operating Segments | Chicago/Minneapolis
Segment Reporting Information [Line Items]
Assets	591,792	615,186
Operating Segments | Florida
Segment Reporting Information [Line Items]
Assets	547,232	533,861
Operating Segments | Houston
Segment Reporting Information [Line Items]
Assets	568,756	498,584
Operating Segments | Lehigh/Central PA
Segment Reporting Information [Line Items]
Assets	1,210,220	1,210,746
Operating Segments | Philadelphia
Segment Reporting Information [Line Items]
Assets	624,373	665,843
Operating Segments | Southeastern PA
Segment Reporting Information [Line Items]
Assets	48,827	241,128
Operating Segments | Southern California
Segment Reporting Information [Line Items]
Assets	660,688	362,122
Operating Segments | United Kingdom
Segment Reporting Information [Line Items]
Assets	463,162	251,824
Operating Segments | Other
Segment Reporting Information [Line Items]
Assets	1,497,629	1,445,531
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Assets	$ 196,674	$ 71,010

Segment Information (Real Estat

Segment Information (Real Estate Assets by Segment) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Real estate assets	$ 5,705,931	$ 4,949,277
Carolinas/Richmond
Segment Reporting Information [Line Items]
Real estate assets	495,149	491,916
Chicago/Minneapolis
Segment Reporting Information [Line Items]
Real estate assets	545,919	557,782
Florida
Segment Reporting Information [Line Items]
Real estate assets	492,797	483,355
Houston
Segment Reporting Information [Line Items]
Real estate assets	509,100	456,675
Lehigh/Central PA
Segment Reporting Information [Line Items]
Real estate assets	1,151,148	1,121,115
Philadelphia
Segment Reporting Information [Line Items]
Real estate assets	286,568	279,338
Southeastern PA
Segment Reporting Information [Line Items]
Real estate assets	15,467	19,357
Southern California
Segment Reporting Information [Line Items]
Real estate assets	633,450	343,520
United Kingdom
Segment Reporting Information [Line Items]
Real estate assets	347,886	191,552
Other
Segment Reporting Information [Line Items]
Real estate assets	$ 1,228,447	$ 1,004,667

Segment Information (Costs Incu

Segment Information (Costs Incurred on Long-lived Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	$ 921,538	$ 632,038	$ 503,000
Carolinas/Richmond
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	22,220	31,958	51,647
Chicago/Minneapolis
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	3,326	14,246	29,317
Florida
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	41,967	23,832	38,312
Houston
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	77,323	17,522	25,831
Lehigh/Central PA
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	63,926	89,304	176,386
Philadelphia
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	3,326	30,685	57,691
Southeastern PA
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	5,118	9,737	4,824
Southern California
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	298,580	183,842	5,599
United Kingdom
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	165,276	10,501	11,492
Other
Segment Reporting Information [Line Items]
Cost incurred on long-lived assets	$ 240,476	$ 220,411	$ 101,901

Accounting for the Impairment_3

Accounting for the Impairment or Disposal of Long-Lived Assets (Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Discontinued Operation
Operating expense reimbursement									$ 151,276	$ 136,184	$ 167,315
Total revenue	$ 180,281	$ 170,389	$ 174,091	$ 180,128	$ 179,825	$ 170,783	$ 160,747	$ 154,029	704,889	665,384	675,323
Real estate taxes									91,663	83,152	92,920
Other Cost and Expense, Operating									11,994	6,167	5,017
Impairment - real estate assets									32,431	3,946	3,879
Total expense									646,404	539,862	589,424
Interest and other income									12,048	7,734	13,846
Gain on property dispositions									303,200	14,600	0
Income taxes									(7,364)	(1,992)	(1,969)
Income from discontinued operations	$ 115,832	$ 104,332	$ 7,948	$ 98,426	$ 22,579	$ 3,389	$ 8,358	$ 6,913	326,538	41,239	27,129
Income available to common shareholders									318,930	40,274	26,497
Discontinued operations
Discontinued Operation
Revenues									43,393	61,405	48,343
Operating expense reimbursement									12,663	27,024	23,042
Total revenue									56,056	88,429	71,385
Rental property									6,959	17,826	13,783
Real estate taxes									7,354	11,582	6,873
Other Cost and Expense, Operating									(9)	(272)	110
Interest expense									5,812	6,858	9,950
Depreciation and amortization									5,356	19,190	13,642
Impairment - real estate assets									7,257	6,686	0
Total expense									32,729	61,870	44,358
Interest and other income									52	102	104
Gain on property dispositions									303,159	14,578	0
Income taxes									0	0	(2)
Income from discontinued operations									326,538	41,239	27,129
Noncontrolling interest - operating partnership									(7,608)	(965)	(632)
Income available to common shareholders									318,930	40,274	26,497
Capital expenditures on cash basis									$ 6,100	$ 62,400	$ 18,900

Accounting for the Impairment_4

Accounting for the Impairment or Disposal of Long-Lived Assets (Significant Sale) (Details) $ in Thousands, ft² in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Oct. 31, 2016USD ($)aft²bldg	Dec. 31, 2018USD ($)bldg	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)bldg	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)bldg	Dec. 31, 2017USD ($)bldg	Dec. 31, 2016USD ($)
Real Estate [Line Items]
Number of buildings (in buildings) | bldg		60								60
Net income		$ 173,916	$ 154,072	$ 20,890	$ 143,725	$ 131,824	$ 61,159	$ 52,818	$ 44,244	$ 492,603	$ 290,045	$ 366,145
Noncontrolling interest – operating partnership										(11,886)	(7,224)	(9,070)
Income available to common shareholders										$ 479,607	$ 282,340	356,817
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Real Estate [Line Items]
Number of buildings (in buildings) | bldg		2				8				2	8
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Real Estate Portfolio
Real Estate [Line Items]
Number of buildings (in buildings) | bldg	108
Leaseable square feet (in sqft) | ft²	7.6
Area of land (in acres) | a	26.7
Proceeds from sale of land	$ 969,000
Gains on sale of land and building	$ 179,100
Net income												48,609
Noncontrolling interest – operating partnership												(1,142)
Income available to common shareholders												$ 47,467

Accounting for the Impairment_5

Accounting for the Impairment or Disposal of Long-Lived Assets (Assets Held for Sale) (Details) ft² in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2019USD ($)ft²bldg	Dec. 31, 2018USD ($)abldg	Dec. 31, 2017USD ($)abldg	Dec. 31, 2016USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		60
Gross proceeds		$ 849,528	$ 379,139	$ 1,192,918
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Assets held for sale		220,545	622,575
Liabilities held for sale		$ 3,183	$ 14,623
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		49
Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		10	27
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Land and land improvements		$ 92,889	$ 155,974
Buildings and improvements		126,001	493,615
Development in progress		0	45,035
Land held for development		0	0
Accumulated depreciation		(36,569)	(187,335)
Deferred financing and leasing costs, net		2,781	15,296
Other assets		3,575	19,351
Assets held for sale		188,677	541,936
Liabilities held for sale		$ 3,042	$ 13,470
Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		37	2
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		11
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		2	8
Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		1
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Land and land improvements		$ 1,301	$ 3,476
Buildings and improvements		5,638	80,738
Development in progress		0	0
Land held for development		26,253	863
Accumulated depreciation		(1,546)	(11,785)
Deferred financing and leasing costs, net		58	2,210
Other assets		164	5,137
Assets held for sale		31,868	80,639
Liabilities held for sale		$ 141	$ 1,153
Held for Sale, Includes Disposal Groups and Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		11	25
Area of land (in acres) | a		69	9
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Land and land improvements		$ 94,190	$ 159,450
Buildings and improvements		131,639	574,353
Development in progress		0	45,035
Land held for development		26,253	863
Accumulated depreciation		(38,115)	(199,120)
Deferred financing and leasing costs, net		2,839	17,506
Other assets		3,739	24,488
Assets held for sale		220,545	622,575
Liabilities held for sale		$ 3,183	$ 14,623
Disposed of by Sale, Discontinued Operations and Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		39	10
Florida | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		3
Florida | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		0	0
Houston | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		0
Houston | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg		0	1
Subsequent Event | Florida | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings (in buildings) | bldg	3
Area of real estate property (in sqft) | ft²	151
Gross proceeds	$ 23,400

Accounting for the Impairment_6

Accounting for the Impairment or Disposal of Long-Lived Assets (Asset Impairments in Reportable Segments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Asset impairment charges	$ 39,688	$ 10,632	$ 3,879
Impairment - real estate assets	32,431	3,946	3,879
Florida
Segment Reporting Information [Line Items]
Asset impairment charges	2,396	0	0
Houston
Segment Reporting Information [Line Items]
Asset impairment charges	0	10,632	0
Chicago/Minneapolis
Segment Reporting Information [Line Items]
Asset impairment charges	2,456	0	3,879
Southeastern PA
Segment Reporting Information [Line Items]
Asset impairment charges	1,579	0	0
Other
Segment Reporting Information [Line Items]
Asset impairment charges	7,257	0	0
Philadelphia
Segment Reporting Information [Line Items]
Asset impairment charges	26,000	0	$ 0
Discontinued operations
Segment Reporting Information [Line Items]
Asset impairment charges	7,300	6,700
Land and Land Improvements | impairment - real estate assets
Segment Reporting Information [Line Items]
Asset impairment charges	6,400	$ 3,900
Land Held for Development | Philadelphia
Segment Reporting Information [Line Items]
Impairment - real estate assets	$ 26,000

Accounting for the Impairment_7

Accounting for the Impairment or Disposal of Long-Lived Assets (Discontinued Operations by Reportable Segment) (Details) - bldg	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	60
Discontinued Operations, Held-for-sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	10	27
Discontinued Operations, Disposed of by Sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	37	2
Florida | Discontinued Operations, Held-for-sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	3
Florida | Discontinued Operations, Disposed of by Sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	0	0
Houston | Discontinued Operations, Held-for-sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	0
Houston | Discontinued Operations, Disposed of by Sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	0	1
Southeastern PA | Discontinued Operations, Held-for-sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	5
Southeastern PA | Discontinued Operations, Disposed of by Sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	32	1
Other | Discontinued Operations, Held-for-sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	2
Other | Discontinued Operations, Disposed of by Sale
Segment Reporting Information [Line Items]
Number of buildings (in buildings)	5	0

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2019USD ($)	Dec. 31, 2018USD ($)contract	Dec. 31, 2017USD ($)contract
Interest Rate Derivatives
Reclassification from accumulated other comprehensive loss to decrease in interest expense		$ 8
Assets needed for immediate settlement		$ 4,700
Interest Rate Swap
Interest Rate Derivatives
Number of interest rate swaps contracts (in contracts) | contract		2	3
Aggregate notional amount		$ 66,800	$ 96,200
Interest Rate Lock Commitments
Interest Rate Derivatives
Number of interest rate swaps contracts (in contracts) | contract		2
Aggregate notional amount		$ 200,000
Interest Rate Lock Agreement A
Interest Rate Derivatives
Aggregate notional amount		100,000
Gain on derivative		$ 2,400
Number of instruments expired (in contracts) | contract		1
Subsequent Event | Interest Rate Lock Agreement B
Interest Rate Derivatives
Aggregate notional amount	$ 100,000
Gain on contract termination	$ 3,300

Derivative Instruments (Gains o

Derivative Instruments (Gains or Losses Recognized Related to the Cash Flow Hedges) (Details) - Designated as Hedging Instrument - Cash Flow Hedging - Interest Rate Swap - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Comprehensive Income (Loss)
Derivative [Line Items]
Amount of gain (loss) related to the effective portion recognized in other comprehensive income (loss)	$ (3,477)	$ 176	$ (648)
Interest Expense
Derivative [Line Items]
Amount of gain (loss) related to the effective portion reclassified to interest expense	228	(453)	(1,069)
Amount of gain (loss) related to the ineffective portion recognized in interest expense	$ 91	$ 168	$ (48)

Derivative Instruments (Derivat

Derivative Instruments (Derivatives Designated As Hedging Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivatives	$ 4,649	$ 2,243
Other Liabilities | Interest Rate Swap
Derivative [Line Items]
Derivatives	677	2,243
Other Liabilities | Interest Rate Lock Commitments
Derivative [Line Items]
Derivatives	$ 3,972	$ 0

Supplemental Disclosure to Stat

Supplemental Disclosure to Statements of Cash Flows (Supplemental Disclosures) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Significant Noncash Transactions [Line Items]
Write-off of costs related to early debt extinguishment	$ 0	$ 0	$ 219,000
Unrealized (loss) gain on cash flow hedge	(3,700,000)	605,000	410,000
Capitalized equity-based compensation	972	1,096	1,221
Redemption of noncontrolling interests - common units	0	152	132
Continuing Operations
Other Significant Noncash Transactions [Line Items]
Write-off of fully depreciated/amortized property and deferred costs - properties included in continuing operations	50,169,000	24,985,000	34,399,000
Write-off of depreciated property and deferred costs due to sale/demolition - properties included in continuing operations	20,272,000	15,760,000	461,480,000
Changes in accrued development capital expenditures - properties included in continuing operations	9,078,000	14,723,000	(13,651,000)
Discontinued operations
Other Significant Noncash Transactions [Line Items]
Write-off of fully depreciated/amortized property and deferred costs - properties included in continuing operations	247,000	6,951,000	7,007,000
Write-off of depreciated property and deferred costs due to sale/demolition - properties included in continuing operations	143,572,000	17,335,000	0
Changes in accrued development capital expenditures - properties included in continuing operations	$ (1,880,000)	$ (2,382,000)	$ 2,283,000

Supplemental Disclosure to Co_3

Supplemental Disclosure to Consolidated Statement of Cash Flows (Reconciliation of Cash and Cash Equivalents) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplemental Disclosure to Statements of Cash Flows [Abstract]
Cash and cash equivalents	$ 84,923	$ 11,882	$ 43,642
Restricted cash	10,899	13,803	12,383
Cash and cash equivalents and restricted cash	$ 95,822	$ 25,685	$ 56,025	$ 44,371

Subsequent Events (Details)

Subsequent Events (Details)	2 Months Ended
	Nov. 30, 2018USD ($)agreement	Jan. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Subsequent Event [Line Items]
Debt instrument, face amount			$ 3,105,626,000
Treasury Lock Agreements
Subsequent Event [Line Items]
Interest rate lock agreements (in agreements) | agreement	2
Gain on derivative	$ 5,700,000
Senior Notes | 4.375% Senior Unsecured Notes | Subsequent Event
Subsequent Event [Line Items]
Debt instrument, face amount		$ 350,000,000
Stated interest rate		4.375%

Schedule II (Details)

Schedule II (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	$ 6,612	$ 7,332	$ 6,898
Additions	7,356	8,977	5,774
Deductions	(7,552)	(9,697)	(5,340)
Balance at End of the Year	6,416	6,612	7,332
Allowance for Trade Receivable, Straight Line Rent [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	549	530	581
Additions	1,431	1,729	824
Deductions	(647)	(1,710)	(875)
Balance at End of the Year	1,333	549	530
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	6,063	6,802	6,317
Additions	5,925	7,248	4,950
Deductions	(6,905)	(7,987)	(4,465)
Balance at End of the Year	$ 5,083	$ 6,063	$ 6,802

Schedule III (Details)

Schedule III (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				$ 45,926,884
Initial Cost of Land				1,626,394,997
Initial Cost of Buildings				2,455,572,009
Costs Capitalized Subsequent to Acquisition				2,484,311,716
Land and Improvements				1,552,949,573
Building and Improvements				5,127,952,770
Gross Amount Carried at End of Period	$ 5,800,901,000	$ 5,483,640,000	$ 6,324,860,000	6,680,903,343
Accumulated Depreciation	851,624,000	746,539,000	973,077,000	974,972,397
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,800,901,000	5,483,640,000	6,324,860,000
Real Estate Additions	1,390,838,000	648,742,000	445,142,000
Real Estate, Cost of Real Estate Sold	(510,836,000)	(331,481,000)	(1,286,362,000)
Real Estate, Gross	6,680,903,343	5,800,901,000	5,483,640,000
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	851,624,000	746,539,000	973,077,000
Real Estate Accumulated Depreciation, Depreciation Expense	143,652,000	149,044,000	168,077,000
Real Estate Accumulated Depreciation, Real Estate Sold	(20,304,000)	(43,959,000)	(394,615,000)
Real Estate Accumulated Depreciation	974,972,397	$ 851,624,000	$ 746,539,000
Athene, New York Life and Wells Fargo [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				347,900,000
Operating Properties [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				45,926,884
Initial Cost of Land				1,071,864,310
Initial Cost of Buildings				2,336,735,248
Costs Capitalized Subsequent to Acquisition				2,520,891,843
Land and Improvements				1,256,705,693
Building and Improvements				4,655,783,748
Gross Amount Carried at End of Period	5,912,490,441			5,912,490,441
Accumulated Depreciation	974,972,397			974,972,397
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,912,490,441
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	974,972,397
Operating Properties [Member] | 1467 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				12,052,635
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				35,350,875
Land and Improvements				12,334,030
Building and Improvements				35,069,480
Gross Amount Carried at End of Period	47,403,510			47,403,510
Accumulated Depreciation	4,214,259			4,214,259
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	47,403,510
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,214,259
Operating Properties [Member] | 1501 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,813,324
Initial Cost of Buildings				18,874,059
Costs Capitalized Subsequent to Acquisition				6,378,428
Land and Improvements				5,816,839
Building and Improvements				25,248,972
Gross Amount Carried at End of Period	31,065,811			31,065,811
Accumulated Depreciation	8,227,740			8,227,740
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	31,065,811
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,227,740
Operating Properties [Member] | 869 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,194,223
Initial Cost of Buildings				4,201,881
Costs Capitalized Subsequent to Acquisition				230,036
Land and Improvements				1,194,223
Building and Improvements				4,431,918
Gross Amount Carried at End of Period	5,626,141			5,626,141
Accumulated Depreciation	658,252			658,252
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,626,141
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	658,252
Operating Properties [Member] | 901 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,055,066
Initial Cost of Buildings				5,984,093
Costs Capitalized Subsequent to Acquisition				879,888
Land and Improvements				2,055,066
Building and Improvements				6,863,981
Gross Amount Carried at End of Period	8,919,047			8,919,047
Accumulated Depreciation	1,230,963			1,230,963
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,919,047
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,230,963
Operating Properties [Member] | 8620 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				38,328,000
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				36,647,068
Land and Improvements				38,328,000
Building and Improvements				36,647,068
Gross Amount Carried at End of Period	74,975,068			74,975,068
Accumulated Depreciation	3,101,872			3,101,872
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	74,975,068
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,101,872
Operating Properties [Member] | 200 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,722,683
Initial Cost of Buildings				18,922,645
Costs Capitalized Subsequent to Acquisition				2,434,125
Land and Improvements				4,722,683
Building and Improvements				21,356,770
Gross Amount Carried at End of Period	26,079,453			26,079,453
Accumulated Depreciation	7,396,339			7,396,339
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	26,079,453
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,396,339
Operating Properties [Member] | 250 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,599,936
Initial Cost of Buildings				12,099,145
Costs Capitalized Subsequent to Acquisition				2,199,097
Land and Improvements				3,717,733
Building and Improvements				14,180,445
Gross Amount Carried at End of Period	17,898,178			17,898,178
Accumulated Depreciation	5,997,398			5,997,398
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	17,898,178
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,997,398
Operating Properties [Member] | 400 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,065,500
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				31,538,572
Land and Improvements				8,184,096
Building and Improvements				31,419,976
Gross Amount Carried at End of Period	39,604,072			39,604,072
Accumulated Depreciation	16,558,762			16,558,762
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	39,604,072
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	16,558,762
Operating Properties [Member] | 650 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,208,248
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				32,440,853
Land and Improvements				9,961,788
Building and Improvements				27,687,313
Gross Amount Carried at End of Period	37,649,101			37,649,101
Accumulated Depreciation	11,327,870			11,327,870
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	37,649,101
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	11,327,870
Operating Properties [Member] | 651 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,308,646
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				18,551,417
Land and Improvements				4,308,646
Building and Improvements				18,551,417
Gross Amount Carried at End of Period	22,860,063			22,860,063
Accumulated Depreciation	10,468,080			10,468,080
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,860,063
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	10,468,080
Operating Properties [Member] | 700 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,473,120
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				20,401,484
Land and Improvements				4,174,970
Building and Improvements				19,699,634
Gross Amount Carried at End of Period	23,874,604			23,874,604
Accumulated Depreciation	11,536,583			11,536,583
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	23,874,604
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	11,536,583
Operating Properties [Member] | 705 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,594,027
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				28,810,136
Land and Improvements				10,596,767
Building and Improvements				28,807,396
Gross Amount Carried at End of Period	39,404,163			39,404,163
Accumulated Depreciation	17,664,832			17,664,832
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	39,404,163
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	17,664,832
Operating Properties [Member] | 7165 Ambassador Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				792,999
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,694,609
Land and Improvements				804,848
Building and Improvements				4,682,760
Gross Amount Carried at End of Period	5,487,608			5,487,608
Accumulated Depreciation	2,265,255			2,265,255
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,487,608
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,265,255
Operating Properties [Member] | 7248 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,670,849
Initial Cost of Buildings				13,307,408
Costs Capitalized Subsequent to Acquisition				4,665,457
Land and Improvements				2,670,673
Building and Improvements				17,973,041
Gross Amount Carried at End of Period	20,643,714			20,643,714
Accumulated Depreciation	9,990,484			9,990,484
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,643,714
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	9,990,484
Operating Properties [Member] | 7339 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,187,776
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,592,257
Land and Improvements				1,197,447
Building and Improvements				7,582,586
Gross Amount Carried at End of Period	8,780,033			8,780,033
Accumulated Depreciation	4,441,217			4,441,217
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,780,033
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,441,217
Operating Properties [Member] | 7437 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				717,488
Initial Cost of Buildings				5,022,413
Costs Capitalized Subsequent to Acquisition				4,003,719
Land and Improvements				726,651
Building and Improvements				9,016,968
Gross Amount Carried at End of Period	9,743,619			9,743,619
Accumulated Depreciation	5,686,680			5,686,680
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,743,619
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,686,680
Operating Properties [Member] | 8014 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,019,258
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,646,983
Land and Improvements				3,645,117
Building and Improvements				13,021,124
Gross Amount Carried at End of Period	16,666,241			16,666,241
Accumulated Depreciation	5,718,258			5,718,258
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,666,241
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,718,258
Operating Properties [Member] | 8150 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,564,167
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,443,051
Land and Improvements				2,571,466
Building and Improvements				9,435,752
Gross Amount Carried at End of Period	12,007,218			12,007,218
Accumulated Depreciation	4,279,822			4,279,822
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,007,218
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,279,822
Operating Properties [Member] | 8250 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,025,667
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,254,712
Land and Improvements				1,035,854
Building and Improvements				5,244,525
Gross Amount Carried at End of Period	6,280,379			6,280,379
Accumulated Depreciation	2,154,620			2,154,620
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,280,379
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,154,620
Operating Properties [Member] | 8400 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,725,948
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				27,402,563
Land and Improvements				7,521,211
Building and Improvements				26,607,300
Gross Amount Carried at End of Period	34,128,511			34,128,511
Accumulated Depreciation	8,740,124			8,740,124
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	34,128,511
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,740,124
Operating Properties [Member] | 6330 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				531,268
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,029,991
Land and Improvements				532,047
Building and Improvements				6,029,212
Gross Amount Carried at End of Period	6,561,259			6,561,259
Accumulated Depreciation	4,218,156			4,218,156
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,561,259
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,218,156
Operating Properties [Member] | 6350 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				360,027
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,526,060
Land and Improvements				560,691
Building and Improvements				4,325,396
Gross Amount Carried at End of Period	4,886,087			4,886,087
Accumulated Depreciation	2,757,186			2,757,186
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,886,087
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,757,186
Operating Properties [Member] | 6370 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				540,795
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,369,686
Land and Improvements				541,459
Building and Improvements				4,369,022
Gross Amount Carried at End of Period	4,910,481			4,910,481
Accumulated Depreciation	2,735,162			2,735,162
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,910,481
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,735,162
Operating Properties [Member] | 6390 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				707,203
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,446,028
Land and Improvements				707,867
Building and Improvements				3,445,364
Gross Amount Carried at End of Period	4,153,231			4,153,231
Accumulated Depreciation	2,054,135			2,054,135
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,153,231
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,054,135
Operating Properties [Member] | 6520 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				453,315
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,589,269
Land and Improvements				484,361
Building and Improvements				1,558,223
Gross Amount Carried at End of Period	2,042,584			2,042,584
Accumulated Depreciation	770,493			770,493
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,042,584
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	770,493
Operating Properties [Member] | 6540 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				422,042
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,337,127
Land and Improvements				422,730
Building and Improvements				5,336,439
Gross Amount Carried at End of Period	5,759,169			5,759,169
Accumulated Depreciation	3,335,623			3,335,623
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,759,169
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,335,623
Operating Properties [Member] | 6560 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				458,281
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,856,517
Land and Improvements				458,945
Building and Improvements				3,855,853
Gross Amount Carried at End of Period	4,314,798			4,314,798
Accumulated Depreciation	2,468,547			2,468,547
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,314,798
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,468,547
Operating Properties [Member] | 6580 Snowdrift Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				388,328
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,876,767
Land and Improvements				389,081
Building and Improvements				4,876,014
Gross Amount Carried at End of Period	5,265,095			5,265,095
Accumulated Depreciation	3,417,222			3,417,222
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,265,095
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,417,222
Operating Properties [Member] | 7620 Cetronia Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,091,806
Initial Cost of Buildings				3,851,456
Costs Capitalized Subsequent to Acquisition				780,423
Land and Improvements				1,093,724
Building and Improvements				4,629,961
Gross Amount Carried at End of Period	5,723,685			5,723,685
Accumulated Depreciation	2,503,775			2,503,775
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,723,685
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,503,775
Operating Properties [Member] | 2250 East Bardin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances
Initial Cost of Land				4,754,659
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,110,192
Land and Improvements				5,864,850
Building and Improvements				30,284,926
Gross Amount Carried at End of Period	36,149,776			36,149,776
Accumulated Depreciation	434,113			434,113
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	36,149,776
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	434,113
Operating Properties [Member] | 3095 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				200,351
Initial Cost of Buildings				1,729,161
Costs Capitalized Subsequent to Acquisition				255,502
Land and Improvements				200,351
Building and Improvements				1,984,663
Gross Amount Carried at End of Period	2,185,014			2,185,014
Accumulated Depreciation	436,384			436,384
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,185,014
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	436,384
Operating Properties [Member] | 3097 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				188,680
Initial Cost of Buildings				1,721,048
Costs Capitalized Subsequent to Acquisition				405,231
Land and Improvements				188,680
Building and Improvements				2,126,279
Gross Amount Carried at End of Period	2,314,959			2,314,959
Accumulated Depreciation	359,030			359,030
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,314,959
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	359,030
Operating Properties [Member] | 7030 Buford Highway NE [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				919,850
Initial Cost of Buildings				4,051,340
Costs Capitalized Subsequent to Acquisition				954,682
Land and Improvements				919,850
Building and Improvements				5,006,022
Gross Amount Carried at End of Period	5,925,872			5,925,872
Accumulated Depreciation	1,064,051			1,064,051
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,925,872
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,064,051
Operating Properties [Member] | Barton 150 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances
Initial Cost of Land				2,196,955
Initial Cost of Buildings				13,643,981
Costs Capitalized Subsequent to Acquisition				(3,633,742)
Land and Improvements				1,692,997
Building and Improvements				10,514,197
Gross Amount Carried at End of Period	12,207,194			12,207,194
Accumulated Depreciation	1,647,568			1,647,568
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,207,194
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,647,568
Operating Properties [Member] | 1055-1071 Kingsland Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				727,294
Initial Cost of Buildings				2,367,529
Costs Capitalized Subsequent to Acquisition				706,473
Land and Improvements				727,294
Building and Improvements				3,074,002
Gross Amount Carried at End of Period	3,801,296			3,801,296
Accumulated Depreciation	659,693			659,693
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,801,296
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	659,693
Operating Properties [Member] | 4606 Richlynn Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				299,600
Initial Cost of Buildings				1,818,861
Costs Capitalized Subsequent to Acquisition				722,788
Land and Improvements				299,600
Building and Improvements				2,541,649
Gross Amount Carried at End of Period	2,841,249			2,841,249
Accumulated Depreciation	1,231,732			1,231,732
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,841,249
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,231,732
Operating Properties [Member] | 11800 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,769,962
Initial Cost of Buildings				1,829,028
Costs Capitalized Subsequent to Acquisition				267,937
Land and Improvements				2,663,725
Building and Improvements				2,203,203
Gross Amount Carried at End of Period	4,866,928			4,866,928
Accumulated Depreciation	430,470			430,470
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,866,928
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	430,470
Operating Properties [Member] | 11850 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,595,044
Initial Cost of Buildings				2,415,132
Costs Capitalized Subsequent to Acquisition				164,477
Land and Improvements				3,457,162
Building and Improvements				2,717,491
Gross Amount Carried at End of Period	6,174,653			6,174,653
Accumulated Depreciation	759,246			759,246
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,174,653
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	759,246
Operating Properties [Member] | 11900 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,492,036
Initial Cost of Buildings				2,024,038
Costs Capitalized Subsequent to Acquisition				520,179
Land and Improvements				3,358,104
Building and Improvements				2,678,149
Gross Amount Carried at End of Period	6,036,253			6,036,253
Accumulated Depreciation	851,104			851,104
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,036,253
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	851,104
Operating Properties [Member] | 12104 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,021,752
Initial Cost of Buildings				2,503,802
Costs Capitalized Subsequent to Acquisition				339,825
Land and Improvements				2,021,752
Building and Improvements				2,843,627
Gross Amount Carried at End of Period	4,865,379			4,865,379
Accumulated Depreciation	765,205			765,205
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,865,379
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	765,205
Operating Properties [Member] | 12200 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,347,882
Initial Cost of Buildings				1,460,291
Costs Capitalized Subsequent to Acquisition				623,867
Land and Improvements				1,347,882
Building and Improvements				2,084,158
Gross Amount Carried at End of Period	3,432,040			3,432,040
Accumulated Depreciation	479,038			479,038
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,432,040
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	479,038
Operating Properties [Member] | 12240 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,479,307
Initial Cost of Buildings				2,159,997
Costs Capitalized Subsequent to Acquisition				791,665
Land and Improvements				1,479,307
Building and Improvements				2,951,663
Gross Amount Carried at End of Period	4,430,970			4,430,970
Accumulated Depreciation	635,369			635,369
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,430,970
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	635,369
Operating Properties [Member] | 1071 Thorndale Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,173,006
Initial Cost of Buildings				2,280,788
Costs Capitalized Subsequent to Acquisition				291,248
Land and Improvements				2,016,715
Building and Improvements				2,728,327
Gross Amount Carried at End of Period	4,745,042			4,745,042
Accumulated Depreciation	605,234			605,234
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,745,042
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	605,234
Operating Properties [Member] | 1260-1274 Ellis Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,298,560
Initial Cost of Buildings				4,020,382
Costs Capitalized Subsequent to Acquisition				360,126
Land and Improvements				2,298,560
Building and Improvements				4,380,508
Gross Amount Carried at End of Period	6,679,068			6,679,068
Accumulated Depreciation	910,658			910,658
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,679,068
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	910,658
Operating Properties [Member] | 371-377 Meyer Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,903,423
Initial Cost of Buildings				3,563,953
Costs Capitalized Subsequent to Acquisition				581,650
Land and Improvements				1,903,423
Building and Improvements				4,145,603
Gross Amount Carried at End of Period	6,049,026			6,049,026
Accumulated Depreciation	835,950			835,950
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,049,026
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	835,950
Operating Properties [Member] | 350 North York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Initial Cost of Land				3,043,130
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(1,288,668)
Land and Improvements				1,754,462
Building and Improvements				4,763,320
Gross Amount Carried at End of Period	6,517,782			6,517,782
Accumulated Depreciation	1,668			1,668
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,517,782
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,668
Operating Properties [Member] | 850-880 Devon Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,958,756
Initial Cost of Buildings				7,959,013
Costs Capitalized Subsequent to Acquisition				780,065
Land and Improvements				2,958,756
Building and Improvements				8,739,078
Gross Amount Carried at End of Period	11,697,834			11,697,834
Accumulated Depreciation	1,719,794			1,719,794
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,697,834
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,719,794
Operating Properties [Member] | 10 Emery Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,591,216
Initial Cost of Buildings				32,941,818
Costs Capitalized Subsequent to Acquisition				8,083,706
Land and Improvements				8,947,574
Building and Improvements				37,669,166
Gross Amount Carried at End of Period	46,616,740			46,616,740
Accumulated Depreciation	6,155,898			6,155,898
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	46,616,740
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	6,155,898
Operating Properties [Member] | 2785 Commerce Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,961,623
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				46,707,077
Land and Improvements				12,009,985
Building and Improvements				46,658,715
Gross Amount Carried at End of Period	58,668,700			58,668,700
Accumulated Depreciation	7,007,059			7,007,059
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	58,668,700
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,007,059
Operating Properties [Member] | 1455 Remington Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,501,294
Initial Cost of Buildings				10,704,719
Costs Capitalized Subsequent to Acquisition				26,008
Land and Improvements				2,501,294
Building and Improvements				10,730,727
Gross Amount Carried at End of Period	13,232,021			13,232,021
Accumulated Depreciation	1,725,320			1,725,320
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,232,021
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,725,320
Operating Properties [Member] | 150 E Crossroads Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,078,949
Initial Cost of Buildings				14,143,377
Costs Capitalized Subsequent to Acquisition				1,303,328
Land and Improvements				3,078,949
Building and Improvements				15,446,705
Gross Amount Carried at End of Period	18,525,654			18,525,654
Accumulated Depreciation	2,859,514			2,859,514
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	18,525,654
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,859,514
Operating Properties [Member] | 553 S Joliet Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,764,831
Initial Cost of Buildings				15,109,947
Costs Capitalized Subsequent to Acquisition				2,933,005
Land and Improvements				3,764,831
Building and Improvements				18,042,952
Gross Amount Carried at End of Period	21,807,783			21,807,783
Accumulated Depreciation	3,595,146			3,595,146
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,807,783
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,595,146
Operating Properties [Member] | 400 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,859,106
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,772,102
Land and Improvements				2,865,575
Building and Improvements				12,765,633
Gross Amount Carried at End of Period	15,631,208			15,631,208
Accumulated Depreciation	4,196,273			4,196,273
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,631,208
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,196,273
Operating Properties [Member] | 8201 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,089,719
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,261,318
Land and Improvements				2,222,168
Building and Improvements				9,128,869
Gross Amount Carried at End of Period	11,351,037			11,351,037
Accumulated Depreciation	2,428,891			2,428,891
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,351,037
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,428,891
Operating Properties [Member] | 8451 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,752,708
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				40,889,400
Land and Improvements				11,511,499
Building and Improvements				38,130,609
Gross Amount Carried at End of Period	49,642,108			49,642,108
Accumulated Depreciation	12,471,964			12,471,964
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	49,642,108
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	12,471,964
Operating Properties [Member] | 860 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,118,881
Initial Cost of Buildings				18,885,486
Costs Capitalized Subsequent to Acquisition				7,522,275
Land and Improvements				8,118,881
Building and Improvements				26,407,761
Gross Amount Carried at End of Period	34,526,642			34,526,642
Accumulated Depreciation	11,645,718			11,645,718
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	34,526,642
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	11,645,718
Operating Properties [Member] | 3525 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,391,065
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,767,103
Land and Improvements				1,629,677
Building and Improvements				5,528,491
Gross Amount Carried at End of Period	7,158,168			7,158,168
Accumulated Depreciation	219,606			219,606
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,158,168
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	219,606
Operating Properties [Member] | 3535 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,807,020
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,458,307
Land and Improvements				3,077,350
Building and Improvements				9,187,977
Gross Amount Carried at End of Period	12,265,327			12,265,327
Accumulated Depreciation	333,446			333,446
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,265,327
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	333,446
Operating Properties [Member] | Tesco Trucking Station [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,755,835
Initial Cost of Buildings				20,336,288
Costs Capitalized Subsequent to Acquisition				29,673,532
Land and Improvements				5,755,835
Building and Improvements				23,917,697
Gross Amount Carried at End of Period	29,673,532			29,673,532
Accumulated Depreciation	200,687			200,687
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	29,673,532
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	200,687
Operating Properties [Member] | 100 Carolina Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,830,187
Costs Capitalized Subsequent to Acquisition				32,143,152
Land and Improvements				10,830,187
Building and Improvements				32,143,152
Gross Amount Carried at End of Period	42,973,339			42,973,339
Accumulated Depreciation	538,847			538,847
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	42,973,339
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	538,847
Operating Properties [Member] | 105 Amor Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,529,232
Land and Improvements				5,229,867
Building and Improvements				2,299,365
Gross Amount Carried at End of Period	7,529,232			7,529,232
Accumulated Depreciation	30,122			30,122
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,529,232
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	30,122
Operating Properties [Member] | 1485 W Commerce Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,249,868
Initial Cost of Buildings				13,886,039
Costs Capitalized Subsequent to Acquisition				2,344,063
Land and Improvements				4,095,262
Building and Improvements				16,384,708
Gross Amount Carried at End of Period	20,479,970			20,479,970
Accumulated Depreciation	7,258,566			7,258,566
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,479,970
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,258,566
Operating Properties [Member] | 40 Logistics Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,981,850
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				33,016,988
Land and Improvements				8,081,272
Building and Improvements				32,917,566
Gross Amount Carried at End of Period	40,998,838			40,998,838
Accumulated Depreciation	6,179,664			6,179,664
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	40,998,838
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	6,179,664
Operating Properties [Member] | 135-195 East Elk Trail [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,873,094
Initial Cost of Buildings				12,430,320
Costs Capitalized Subsequent to Acquisition				2,711,630
Land and Improvements				4,873,094
Building and Improvements				15,141,950
Gross Amount Carried at End of Period	20,015,044			20,015,044
Accumulated Depreciation	2,164,779			2,164,779
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,015,044
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,164,779
Operating Properties [Member] | 515 Kehoe Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,523,427
Initial Cost of Buildings				14,581,705
Costs Capitalized Subsequent to Acquisition				1,016,882
Land and Improvements				5,523,427
Building and Improvements				15,598,587
Gross Amount Carried at End of Period	21,122,014			21,122,014
Accumulated Depreciation	2,222,829			2,222,829
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,122,014
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,222,829
Operating Properties [Member] | 1413 Bradley Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				247,477
Initial Cost of Buildings				2,028,322
Costs Capitalized Subsequent to Acquisition				233,527
Land and Improvements				247,477
Building and Improvements				2,261,849
Gross Amount Carried at End of Period	2,509,326			2,509,326
Accumulated Depreciation	255,915			255,915
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,509,326
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	255,915
Operating Properties [Member] | 3200 Belmeade Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,042,453
Initial Cost of Buildings				8,027,974
Costs Capitalized Subsequent to Acquisition				595,707
Land and Improvements				1,042,453
Building and Improvements				8,623,681
Gross Amount Carried at End of Period	9,666,134			9,666,134
Accumulated Depreciation	1,493,508			1,493,508
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,666,134
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,493,508
Operating Properties [Member] | 16325 S Avalon Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				26,432,369
Initial Cost of Buildings				19,669,675
Costs Capitalized Subsequent to Acquisition				387,002
Land and Improvements				26,476,167
Building and Improvements				20,012,879
Gross Amount Carried at End of Period	46,489,046			46,489,046
Accumulated Depreciation	669,481			669,481
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	46,489,046
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	669,481
Operating Properties [Member] | 1475 Nitterhouse Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,081,007
Initial Cost of Buildings				39,002,011
Costs Capitalized Subsequent to Acquisition				2,091,556
Land and Improvements				7,081,007
Building and Improvements				41,093,567
Gross Amount Carried at End of Period	48,174,574			48,174,574
Accumulated Depreciation	7,376,996			7,376,996
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	48,174,574
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,376,996
Operating Properties [Member] | 95 Kriner Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,695,501
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				35,058,041
Land and Improvements				9,407,871
Building and Improvements				34,345,671
Gross Amount Carried at End of Period	43,753,542			43,753,542
Accumulated Depreciation	10,389,249			10,389,249
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	43,753,542
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	10,389,249
Operating Properties [Member] | 9000 109th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,251,043
Initial Cost of Buildings				11,662,995
Costs Capitalized Subsequent to Acquisition				119,919
Land and Improvements				1,251,043
Building and Improvements				11,782,914
Gross Amount Carried at End of Period	13,033,957			13,033,957
Accumulated Depreciation	2,461,549			2,461,549
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,033,957
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,461,549
Operating Properties [Member] | 11701 Goodrich Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,054,621
Initial Cost of Buildings				6,356,151
Costs Capitalized Subsequent to Acquisition				1,022,332
Land and Improvements				2,054,621
Building and Improvements				7,378,482
Gross Amount Carried at End of Period	9,433,103			9,433,103
Accumulated Depreciation	1,633,427			1,633,427
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,433,103
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,633,427
Operating Properties [Member] | 12810 Virkler Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				475,368
Initial Cost of Buildings				2,367,586
Costs Capitalized Subsequent to Acquisition				921,907
Land and Improvements				476,262
Building and Improvements				3,288,598
Gross Amount Carried at End of Period	3,764,860			3,764,860
Accumulated Depreciation	662,261			662,261
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,764,860
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	662,261
Operating Properties [Member] | 2700 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				912,500
Initial Cost of Buildings				4,721,259
Costs Capitalized Subsequent to Acquisition				366,811
Land and Improvements				912,500
Building and Improvements				5,088,070
Gross Amount Carried at End of Period	6,000,570			6,000,570
Accumulated Depreciation	1,049,544			1,049,544
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,000,570
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,049,544
Operating Properties [Member] | 2701 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,275,000
Initial Cost of Buildings				4,649,750
Costs Capitalized Subsequent to Acquisition				684,784
Land and Improvements				1,275,000
Building and Improvements				5,334,534
Gross Amount Carried at End of Period	6,609,534			6,609,534
Accumulated Depreciation	1,115,197			1,115,197
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,609,534
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,115,197
Operating Properties [Member] | 2730 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,878,750
Initial Cost of Buildings				10,129,499
Costs Capitalized Subsequent to Acquisition				170,089
Land and Improvements				1,878,750
Building and Improvements				10,299,588
Gross Amount Carried at End of Period	12,178,338			12,178,338
Accumulated Depreciation	1,967,588			1,967,588
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,178,338
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,967,588
Operating Properties [Member] | 2801 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,065,000
Initial Cost of Buildings				6,975,250
Costs Capitalized Subsequent to Acquisition				813,680
Land and Improvements				1,065,000
Building and Improvements				7,788,930
Gross Amount Carried at End of Period	8,853,930			8,853,930
Accumulated Depreciation	1,490,060			1,490,060
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,853,930
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,490,060
Operating Properties [Member] | 3000 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,831,250
Initial Cost of Buildings				10,779,412
Costs Capitalized Subsequent to Acquisition				1,146,648
Land and Improvements				1,831,250
Building and Improvements				11,926,060
Gross Amount Carried at End of Period	13,757,310			13,757,310
Accumulated Depreciation	2,435,771			2,435,771
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,757,310
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,435,771
Operating Properties [Member] | 3005 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,990,000
Initial Cost of Buildings				6,561,540
Costs Capitalized Subsequent to Acquisition				1,169,186
Land and Improvements				1,990,000
Building and Improvements				7,730,726
Gross Amount Carried at End of Period	9,720,726			9,720,726
Accumulated Depreciation	1,619,220			1,619,220
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,720,726
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,619,220
Operating Properties [Member] | 4045 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,418,928
Initial Cost of Buildings				7,511,050
Costs Capitalized Subsequent to Acquisition				631,990
Land and Improvements				1,418,928
Building and Improvements				8,143,040
Gross Amount Carried at End of Period	9,561,968			9,561,968
Accumulated Depreciation	1,703,407			1,703,407
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,561,968
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,703,407
Operating Properties [Member] | 4047 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,279,004
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,399,096
Land and Improvements				1,279,004
Building and Improvements				6,399,096
Gross Amount Carried at End of Period	7,678,100			7,678,100
Accumulated Depreciation	1,281,462			1,281,462
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,678,100
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,281,462
Operating Properties [Member] | 4525 Statesville Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				841,250
Initial Cost of Buildings				5,279,315
Costs Capitalized Subsequent to Acquisition				667,246
Land and Improvements				837,144
Building and Improvements				5,950,667
Gross Amount Carried at End of Period	6,787,811			6,787,811
Accumulated Depreciation	1,047,780			1,047,780
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,787,811
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,047,780
Operating Properties [Member] | 4835 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				3,194,355
Initial Cost of Land				690,750
Initial Cost of Buildings				5,086,388
Costs Capitalized Subsequent to Acquisition				94,118
Land and Improvements				690,750
Building and Improvements				5,180,506
Gross Amount Carried at End of Period	5,871,256			5,871,256
Accumulated Depreciation	865,138			865,138
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,871,256
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	865,138
Operating Properties [Member] | 4925 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				3,227,439
Initial Cost of Land				603,003
Initial Cost of Buildings				4,969,011
Costs Capitalized Subsequent to Acquisition				152,435
Land and Improvements				603,003
Building and Improvements				5,121,446
Gross Amount Carried at End of Period	5,724,449			5,724,449
Accumulated Depreciation	968,523			968,523
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,724,449
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	968,523
Operating Properties [Member] | 5032 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,416,763
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,030,334
Land and Improvements				1,416,763
Building and Improvements				9,030,334
Gross Amount Carried at End of Period	10,447,097			10,447,097
Accumulated Depreciation	776,614			776,614
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,447,097
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	776,614
Operating Properties [Member] | 5033 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				2,753,026
Initial Cost of Land				509,247
Initial Cost of Buildings				4,710,218
Costs Capitalized Subsequent to Acquisition				165,463
Land and Improvements				613,962
Building and Improvements				4,770,966
Gross Amount Carried at End of Period	5,384,928			5,384,928
Accumulated Depreciation	831,612			831,612
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,384,928
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	831,612
Operating Properties [Member] | 5039 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,027,500
Initial Cost of Buildings				6,172,807
Costs Capitalized Subsequent to Acquisition				62,651
Land and Improvements				1,027,500
Building and Improvements				6,235,458
Gross Amount Carried at End of Period	7,262,958			7,262,958
Accumulated Depreciation	670,560			670,560
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,262,958
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	670,560
Operating Properties [Member] | 8910 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				527,873
Initial Cost of Buildings				4,959,206
Costs Capitalized Subsequent to Acquisition				360,419
Land and Improvements				527,873
Building and Improvements				5,319,625
Gross Amount Carried at End of Period	5,847,498			5,847,498
Accumulated Depreciation	983,509			983,509
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,847,498
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	983,509
Operating Properties [Member] | 8916 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				557,730
Initial Cost of Buildings				5,785,333
Costs Capitalized Subsequent to Acquisition				555,839
Land and Improvements				557,730
Building and Improvements				6,341,172
Gross Amount Carried at End of Period	6,898,902			6,898,902
Accumulated Depreciation	1,372,889			1,372,889
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,898,902
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,372,889
Operating Properties [Member] | 8924 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				654,713
Initial Cost of Buildings				5,365,823
Costs Capitalized Subsequent to Acquisition				(55,823)
Land and Improvements				654,713
Building and Improvements				5,310,000
Gross Amount Carried at End of Period	5,964,713			5,964,713
Accumulated Depreciation	269,234			269,234
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,964,713
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	269,234
Operating Properties [Member] | 3923 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,967,121
Land and Improvements				895,209
Building and Improvements				9,071,912
Gross Amount Carried at End of Period	9,967,121			9,967,121
Accumulated Depreciation	70,798			70,798
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,967,121
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	70,798
Operating Properties [Member] | 3929 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				592,233
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				581,457
Land and Improvements				1,173,690
Building and Improvements				10,559,454
Gross Amount Carried at End of Period	11,733,144			11,733,144
Accumulated Depreciation	217,685			217,685
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,733,144
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	217,685
Operating Properties [Member] | 2601 Indian River Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,711,746
Initial Cost of Buildings				10,418,032
Costs Capitalized Subsequent to Acquisition				493,191
Land and Improvements				1,711,746
Building and Improvements				10,911,223
Gross Amount Carried at End of Period	12,622,969			12,622,969
Accumulated Depreciation	1,970,775			1,970,775
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,622,969
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,970,775
Operating Properties [Member] | 1540 S 54th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,540,236
Initial Cost of Buildings				20,130,552
Costs Capitalized Subsequent to Acquisition				928,916
Land and Improvements				3,540,236
Building and Improvements				21,059,468
Gross Amount Carried at End of Period	24,599,704			24,599,704
Accumulated Depreciation	3,668,514			3,668,514
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	24,599,704
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,668,514
Operating Properties [Member] | 4650 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,030,242
Initial Cost of Buildings				4,003,024
Costs Capitalized Subsequent to Acquisition				388,666
Land and Improvements				1,030,242
Building and Improvements				4,391,689
Gross Amount Carried at End of Period	5,421,931			5,421,931
Accumulated Depreciation	870,081			870,081
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,421,931
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	870,081
Operating Properties [Member] | 4750 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,138,166
Initial Cost of Buildings				5,914,789
Costs Capitalized Subsequent to Acquisition				240,972
Land and Improvements				1,138,166
Building and Improvements				6,155,761
Gross Amount Carried at End of Period	7,293,927			7,293,927
Accumulated Depreciation	1,122,251			1,122,251
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,293,927
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,122,251
Operating Properties [Member] | 15025 Proctor Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				27,991,514
Land and Improvements				16,149,929
Building and Improvements				11,841,585
Gross Amount Carried at End of Period	27,991,514			27,991,514
Accumulated Depreciation	26,802			26,802
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	27,991,514
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	26,802
Operating Properties [Member] | 9645 Gerwig Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,915,960
Initial Cost of Buildings				6,461,228
Costs Capitalized Subsequent to Acquisition				507,087
Land and Improvements				1,915,960
Building and Improvements				6,968,315
Gross Amount Carried at End of Period	8,884,275			8,884,275
Accumulated Depreciation	1,143,213			1,143,213
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,884,275
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,143,213
Operating Properties [Member] | 2550 John Glenn Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				540,601
Initial Cost of Buildings				5,129,342
Costs Capitalized Subsequent to Acquisition				1,072,491
Land and Improvements				540,601
Building and Improvements				6,201,833
Gross Amount Carried at End of Period	6,742,434			6,742,434
Accumulated Depreciation	1,046,557			1,046,557
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,742,434
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,046,557
Operating Properties [Member] | 3800 Twin Creeks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				549,393
Initial Cost of Buildings				4,643,302
Costs Capitalized Subsequent to Acquisition				481,884
Land and Improvements				549,393
Building and Improvements				5,125,186
Gross Amount Carried at End of Period	5,674,579			5,674,579
Accumulated Depreciation	891,452			891,452
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,674,579
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	891,452
Operating Properties [Member] | 5959 Randolph St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				88,344,713
Land and Improvements				34,612,210
Building and Improvements				53,732,503
Gross Amount Carried at End of Period	88,344,713			88,344,713
Accumulated Depreciation	1,313,050			1,313,050
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	88,344,713
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,313,050
Operating Properties [Member] | 330 South Royal Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,091,426
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,402,502
Land and Improvements				2,091,426
Building and Improvements				11,402,502
Gross Amount Carried at End of Period	13,493,928			13,493,928
Accumulated Depreciation	1,288,604			1,288,604
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,493,928
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,288,604
Operating Properties [Member] | 455 Airline Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				312,701
Initial Cost of Buildings				2,311,531
Costs Capitalized Subsequent to Acquisition				489,677
Land and Improvements				312,701
Building and Improvements				2,801,208
Gross Amount Carried at End of Period	3,113,909			3,113,909
Accumulated Depreciation	606,996			606,996
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,113,909
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	606,996
Operating Properties [Member] | 2130 Baldwin Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,172,032
Initial Cost of Buildings				7,350,782
Costs Capitalized Subsequent to Acquisition				418,907
Land and Improvements				3,172,032
Building and Improvements				7,769,689
Gross Amount Carried at End of Period	10,941,721			10,941,721
Accumulated Depreciation	1,450,318			1,450,318
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,941,721
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,450,318
Operating Properties [Member] | 11020 Holly Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,536,731
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,279,946
Land and Improvements				2,536,731
Building and Improvements				12,279,946
Gross Amount Carried at End of Period	14,816,677			14,816,677
Accumulated Depreciation	786,823			786,823
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,816,677
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	786,823
Operating Properties [Member] | 329-333 Herrod Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,039,559
Initial Cost of Buildings				20,863,051
Costs Capitalized Subsequent to Acquisition				2,285,014
Land and Improvements				4,039,559
Building and Improvements				23,148,065
Gross Amount Carried at End of Period	27,187,624			27,187,624
Accumulated Depreciation	4,102,628			4,102,628
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	27,187,624
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,102,628
Operating Properties [Member] | 1250 Hall Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				829,570
Initial Cost of Buildings				4,778,327
Costs Capitalized Subsequent to Acquisition				171,544
Land and Improvements				831,611
Building and Improvements				4,947,830
Gross Amount Carried at End of Period	5,779,441			5,779,441
Accumulated Depreciation	1,575,091			1,575,091
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,779,441
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,575,091
Operating Properties [Member] | 333 Howard Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,928,724
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				14,263,106
Land and Improvements				7,928,724
Building and Improvements				14,263,106
Gross Amount Carried at End of Period	22,191,830			22,191,830
Accumulated Depreciation	1,330,094			1,330,094
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,191,830
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,330,094
Operating Properties [Member] | 131 Aldersgate Street & 14-17 Carthusian Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,594,064
Initial Cost of Buildings				1,301,980
Costs Capitalized Subsequent to Acquisition				0
Land and Improvements				3,594,064
Building and Improvements				1,301,980
Gross Amount Carried at End of Period	4,896,044			4,896,044
Accumulated Depreciation	8,199			8,199
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,896,044
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,199
Operating Properties [Member] | 1680 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,928,412
Initial Cost of Buildings				4,651,819
Costs Capitalized Subsequent to Acquisition				1,154,075
Land and Improvements				1,928,412
Building and Improvements				5,805,894
Gross Amount Carried at End of Period	7,734,306			7,734,306
Accumulated Depreciation	1,268,370			1,268,370
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,734,306
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,268,370
Operating Properties [Member] | 1700 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,082,072
Initial Cost of Buildings				2,496,599
Costs Capitalized Subsequent to Acquisition				625,991
Land and Improvements				1,082,072
Building and Improvements				3,122,590
Gross Amount Carried at End of Period	4,204,662			4,204,662
Accumulated Depreciation	776,229			776,229
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,204,662
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	776,229
Operating Properties [Member] | 2670 Breckinridge Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,676,415
Initial Cost of Buildings				4,567,592
Costs Capitalized Subsequent to Acquisition				980,381
Land and Improvements				1,676,415
Building and Improvements				5,547,974
Gross Amount Carried at End of Period	7,224,389			7,224,389
Accumulated Depreciation	1,104,805			1,104,805
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,224,389
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,104,805
Operating Properties [Member] | 170 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				598,348
Initial Cost of Buildings				3,643,756
Costs Capitalized Subsequent to Acquisition				1,228,006
Land and Improvements				598,918
Building and Improvements				4,871,192
Gross Amount Carried at End of Period	5,470,110			5,470,110
Accumulated Depreciation	1,448,618			1,448,618
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,470,110
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,448,618
Operating Properties [Member] | 190 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				551,663
Initial Cost of Buildings				3,310,993
Costs Capitalized Subsequent to Acquisition				251,300
Land and Improvements				552,211
Building and Improvements				3,561,744
Gross Amount Carried at End of Period	4,113,955			4,113,955
Accumulated Depreciation	1,166,823			1,166,823
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,113,955
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,166,823
Operating Properties [Member] | 265 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				901,444
Initial Cost of Buildings				5,751,389
Costs Capitalized Subsequent to Acquisition				193,199
Land and Improvements				902,374
Building and Improvements				5,943,658
Gross Amount Carried at End of Period	6,846,032			6,846,032
Accumulated Depreciation	2,239,383			2,239,383
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,846,032
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,239,383
Operating Properties [Member] | 285 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				975,433
Initial Cost of Buildings				5,851,990
Costs Capitalized Subsequent to Acquisition				1,173,262
Land and Improvements				976,393
Building and Improvements				7,024,292
Gross Amount Carried at End of Period	8,000,685			8,000,685
Accumulated Depreciation	2,105,505			2,105,505
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,000,685
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,105,505
Operating Properties [Member] | 1000 Parliament Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,229,000
Initial Cost of Buildings				7,064,506
Costs Capitalized Subsequent to Acquisition				985,898
Land and Improvements				2,229,000
Building and Improvements				8,050,404
Gross Amount Carried at End of Period	10,279,404			10,279,404
Accumulated Depreciation	978,653			978,653
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,279,404
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	978,653
Operating Properties [Member] | 4226 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,440,000
Initial Cost of Buildings				7,932,265
Costs Capitalized Subsequent to Acquisition				306,380
Land and Improvements				1,440,000
Building and Improvements				8,238,645
Gross Amount Carried at End of Period	9,678,645			9,678,645
Accumulated Depreciation	1,247,620			1,247,620
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,678,645
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,247,620
Operating Properties [Member] | 4227 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,500,000
Initial Cost of Buildings				5,624,030
Costs Capitalized Subsequent to Acquisition				234,711
Land and Improvements				1,500,000
Building and Improvements				5,858,740
Gross Amount Carried at End of Period	7,358,740			7,358,740
Accumulated Depreciation	692,281			692,281
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,358,740
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	692,281
Operating Properties [Member] | 4234 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,440,000
Initial Cost of Buildings				7,356,161
Costs Capitalized Subsequent to Acquisition				(11,072)
Land and Improvements				1,440,000
Building and Improvements				7,345,089
Gross Amount Carried at End of Period	8,785,089			8,785,089
Accumulated Depreciation	982,836			982,836
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,785,089
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	982,836
Operating Properties [Member] | 4300 Emperor Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,576,500
Initial Cost of Buildings				4,240,961
Costs Capitalized Subsequent to Acquisition				189,629
Land and Improvements				1,576,500
Building and Improvements				4,430,590
Gross Amount Carried at End of Period	6,007,090			6,007,090
Accumulated Depreciation	549,462			549,462
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,007,090
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	549,462
Operating Properties [Member] | 1951 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,115,595
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,644,168
Land and Improvements				1,324,734
Building and Improvements				3,435,029
Gross Amount Carried at End of Period	4,759,763			4,759,763
Accumulated Depreciation	188,268			188,268
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,759,763
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	188,268
Operating Properties [Member] | 1953 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,402,820
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,586,494
Land and Improvements				2,853,273
Building and Improvements				6,136,041
Gross Amount Carried at End of Period	8,989,314			8,989,314
Accumulated Depreciation	291,107			291,107
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,989,314
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	291,107
Operating Properties [Member] | 1955 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				758,503
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,120,096
Land and Improvements				2,453,348
Building and Improvements				7,425,251
Gross Amount Carried at End of Period	9,878,599			9,878,599
Accumulated Depreciation	71,932			71,932
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,878,599
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	71,932
Operating Properties [Member] | 1957 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,844,943
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,950,175
Land and Improvements				3,091,046
Building and Improvements				6,704,072
Gross Amount Carried at End of Period	9,795,118			9,795,118
Accumulated Depreciation	411,361			411,361
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,795,118
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	411,361
Operating Properties [Member] | 3169 Dodd Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				988,594
Initial Cost of Buildings				6,586,907
Costs Capitalized Subsequent to Acquisition				225,918
Land and Improvements				988,594
Building and Improvements				6,812,825
Gross Amount Carried at End of Period	7,801,419			7,801,419
Accumulated Depreciation	1,184,526			1,184,526
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,801,419
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,184,526
Operating Properties [Member] | 3711 Kennebec Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				999,702
Initial Cost of Buildings				4,042,589
Costs Capitalized Subsequent to Acquisition				(934)
Land and Improvements				999,702
Building and Improvements				4,041,655
Gross Amount Carried at End of Period	5,041,357			5,041,357
Accumulated Depreciation	866,480			866,480
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,041,357
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	866,480
Operating Properties [Member] | 917 Lone Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,493,115
Initial Cost of Buildings				6,120,455
Costs Capitalized Subsequent to Acquisition				986,900
Land and Improvements				1,493,115
Building and Improvements				7,107,355
Gross Amount Carried at End of Period	8,600,470			8,600,470
Accumulated Depreciation	1,453,058			1,453,058
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,600,470
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,453,058
Operating Properties [Member] | 10301-10305 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				120,622
Initial Cost of Buildings				1,085,226
Costs Capitalized Subsequent to Acquisition				297,669
Land and Improvements				105,657
Building and Improvements				1,397,860
Gross Amount Carried at End of Period	1,503,517			1,503,517
Accumulated Depreciation	756,571			756,571
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,503,517
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	756,571
Operating Properties [Member] | 10321 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				145,198
Initial Cost of Buildings				1,305,700
Costs Capitalized Subsequent to Acquisition				601,349
Land and Improvements				127,181
Building and Improvements				1,925,066
Gross Amount Carried at End of Period	2,052,247			2,052,247
Accumulated Depreciation	1,047,920			1,047,920
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,052,247
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,047,920
Operating Properties [Member] | 10333 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				110,746
Initial Cost of Buildings				995,868
Costs Capitalized Subsequent to Acquisition				330,889
Land and Improvements				97,003
Building and Improvements				1,340,500
Gross Amount Carried at End of Period	1,437,503			1,437,503
Accumulated Depreciation	702,253			702,253
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,437,503
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	702,253
Operating Properties [Member] | 10349-10357 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				275,903
Initial Cost of Buildings				2,481,666
Costs Capitalized Subsequent to Acquisition				945,812
Land and Improvements				241,667
Building and Improvements				3,461,714
Gross Amount Carried at End of Period	3,703,381			3,703,381
Accumulated Depreciation	1,957,160			1,957,160
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,703,381
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,957,160
Operating Properties [Member] | 10365-10375 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				291,077
Initial Cost of Buildings				2,618,194
Costs Capitalized Subsequent to Acquisition				1,575,676
Land and Improvements				255,683
Building and Improvements				4,229,264
Gross Amount Carried at End of Period	4,484,947			4,484,947
Accumulated Depreciation	2,057,137			2,057,137
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,484,947
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,057,137
Operating Properties [Member] | 10393-10394 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				269,618
Initial Cost of Buildings				2,423,318
Costs Capitalized Subsequent to Acquisition				2,574,661
Land and Improvements				236,903
Building and Improvements				5,030,694
Gross Amount Carried at End of Period	5,267,597			5,267,597
Accumulated Depreciation	2,510,427			2,510,427
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,267,597
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,510,427
Operating Properties [Member] | 7075 Flying Cloud Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,232,831
Initial Cost of Buildings				10,855,851
Costs Capitalized Subsequent to Acquisition				4,182,406
Land and Improvements				10,093,396
Building and Improvements				15,177,691
Gross Amount Carried at End of Period	25,271,087			25,271,087
Accumulated Depreciation	4,202,224			4,202,224
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	25,271,087
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,202,224
Operating Properties [Member] | 7078 Shady Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				343,093
Initial Cost of Buildings				3,085,795
Costs Capitalized Subsequent to Acquisition				1,624,490
Land and Improvements				336,481
Building and Improvements				4,716,897
Gross Amount Carried at End of Period	5,053,378			5,053,378
Accumulated Depreciation	2,838,868			2,838,868
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,053,378
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,838,868
Operating Properties [Member] | 1075 King George Post Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				0
Land and Improvements				0
Building and Improvements				14,468,904
Gross Amount Carried at End of Period	14,468,904			14,468,904
Accumulated Depreciation	319,235			319,235
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,468,904
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	319,235
Operating Properties [Member] | 1 Truman Drive South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				27,862,573
Initial Cost of Buildings				19,426,947
Costs Capitalized Subsequent to Acquisition				1,000,379
Land and Improvements				27,909,534
Building and Improvements				20,380,365
Gross Amount Carried at End of Period	48,289,899			48,289,899
Accumulated Depreciation	655,915			655,915
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	48,289,899
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	655,915
Operating Properties [Member] | 2250 Arthur Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,403,196
Initial Cost of Buildings				2,386,396
Costs Capitalized Subsequent to Acquisition				149,086
Land and Improvements				1,403,196
Building and Improvements				2,535,482
Gross Amount Carried at End of Period	3,938,678			3,938,678
Accumulated Depreciation	477,737			477,737
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,938,678
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	477,737
Operating Properties [Member] | 6600 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,680,220
Initial Cost of Buildings				14,671,910
Costs Capitalized Subsequent to Acquisition				701,811
Land and Improvements				3,680,220
Building and Improvements				15,373,721
Gross Amount Carried at End of Period	19,053,941			19,053,941
Accumulated Depreciation	2,426,083			2,426,083
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	19,053,941
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,426,083
Operating Properties [Member] | 6675 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,421,854
Initial Cost of Buildings				9,730,192
Costs Capitalized Subsequent to Acquisition				1,062,508
Land and Improvements				2,421,854
Building and Improvements				10,792,700
Gross Amount Carried at End of Period	13,214,554			13,214,554
Accumulated Depreciation	1,723,311			1,723,311
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,214,554
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,723,311
Operating Properties [Member] | 7351 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,897,044
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,438,573
Land and Improvements				3,023,417
Building and Improvements				6,312,200
Gross Amount Carried at End of Period	9,335,617			9,335,617
Accumulated Depreciation	2,162,388			2,162,388
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,335,617
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,162,388
Operating Properties [Member] | 21705-21707 Mississippi Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,594,259
Initial Cost of Buildings				30,329,802
Costs Capitalized Subsequent to Acquisition				1,560,421
Land and Improvements				10,594,259
Building and Improvements				31,890,224
Gross Amount Carried at End of Period	42,484,483			42,484,483
Accumulated Depreciation	6,130,681			6,130,681
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	42,484,483
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	6,130,681
Operating Properties [Member] | 27143 Elwood International Port Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,022,000
Initial Cost of Buildings				5,612,934
Costs Capitalized Subsequent to Acquisition				587,424
Land and Improvements				6,022,000
Building and Improvements				6,200,358
Gross Amount Carried at End of Period	12,222,358			12,222,358
Accumulated Depreciation	1,261,705			1,261,705
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,222,358
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,261,705
Operating Properties [Member] | 1800 Donaldson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				13,211,604
Costs Capitalized Subsequent to Acquisition				925,430
Land and Improvements				0
Building and Improvements				14,137,034
Gross Amount Carried at End of Period	14,137,034			14,137,034
Accumulated Depreciation	4,921,421			4,921,421
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,137,034
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,921,421
Operating Properties [Member] | 6880 Fairfield Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				412,136
Initial Cost of Buildings				3,029,177
Costs Capitalized Subsequent to Acquisition				146,362
Land and Improvements				412,136
Building and Improvements				3,175,539
Gross Amount Carried at End of Period	3,587,675			3,587,675
Accumulated Depreciation	556,807			556,807
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,587,675
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	556,807
Operating Properties [Member] | 7000-7018 Fairfield Business [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				367,925
Initial Cost of Buildings				2,205,817
Costs Capitalized Subsequent to Acquisition				177,642
Land and Improvements				386,928
Building and Improvements				2,364,456
Gross Amount Carried at End of Period	2,751,384			2,751,384
Accumulated Depreciation	404,637			404,637
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,751,384
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	404,637
Operating Properties [Member] | 10721 Jasmine Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,427,061
Initial Cost of Buildings				23,784,779
Costs Capitalized Subsequent to Acquisition				3,332,270
Land and Improvements				11,427,061
Building and Improvements				27,117,049
Gross Amount Carried at End of Period	38,544,110			38,544,110
Accumulated Depreciation	2,642,439			2,642,439
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	38,544,110
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,642,439
Operating Properties [Member] | 2000 Southpointe Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				756,221
Initial Cost of Buildings				9,115,626
Costs Capitalized Subsequent to Acquisition				619,869
Land and Improvements				756,221
Building and Improvements				9,735,495
Gross Amount Carried at End of Period	10,491,716			10,491,716
Accumulated Depreciation	1,726,418			1,726,418
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,491,716
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,726,418
Operating Properties [Member] | 1400 NW 65th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				545,480
Initial Cost of Buildings				2,540,210
Costs Capitalized Subsequent to Acquisition				85,911
Land and Improvements				545,480
Building and Improvements				2,626,121
Gross Amount Carried at End of Period	3,171,601			3,171,601
Accumulated Depreciation	417,925			417,925
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,171,601
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	417,925
Operating Properties [Member] | 6500 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				3,064,734
Costs Capitalized Subsequent to Acquisition				477,057
Land and Improvements				0
Building and Improvements				3,541,791
Gross Amount Carried at End of Period	3,541,791			3,541,791
Accumulated Depreciation	694,531			694,531
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,541,791
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	694,531
Operating Properties [Member] | 6501 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				519,984
Initial Cost of Buildings				2,677,465
Costs Capitalized Subsequent to Acquisition				312,769
Land and Improvements				519,984
Building and Improvements				2,990,234
Gross Amount Carried at End of Period	3,510,218			3,510,218
Accumulated Depreciation	461,790			461,790
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,510,218
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	461,790
Operating Properties [Member] | 6600 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				2,988,181
Costs Capitalized Subsequent to Acquisition				377,561
Land and Improvements				0
Building and Improvements				3,365,742
Gross Amount Carried at End of Period	3,365,742			3,365,742
Accumulated Depreciation	629,720			629,720
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,365,742
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	629,720
Operating Properties [Member] | 11222 Melrose Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,999,106
Initial Cost of Buildings				4,658,605
Costs Capitalized Subsequent to Acquisition				103,693
Land and Improvements				2,999,106
Building and Improvements				4,762,298
Gross Amount Carried at End of Period	7,761,404			7,761,404
Accumulated Depreciation	458,865			458,865
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,761,404
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	458,865
Operating Properties [Member] | 9601 Cosner Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				475,262
Initial Cost of Buildings				3,917,234
Costs Capitalized Subsequent to Acquisition				387,586
Land and Improvements				475,262
Building and Improvements				4,304,820
Gross Amount Carried at End of Period	4,780,082			4,780,082
Accumulated Depreciation	2,536,776			2,536,776
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,780,082
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,536,776
Operating Properties [Member] | 5410 - 5430 Northwest 33rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				603,776
Initial Cost of Buildings				4,176,238
Costs Capitalized Subsequent to Acquisition				2,081,367
Land and Improvements				625,111
Building and Improvements				6,236,270
Gross Amount Carried at End of Period	6,861,381			6,861,381
Accumulated Depreciation	3,556,017			3,556,017
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,861,381
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,556,017
Operating Properties [Member] | 12601 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,048,143
Initial Cost of Buildings				1,088,697
Costs Capitalized Subsequent to Acquisition				70,518
Land and Improvements				2,048,143
Building and Improvements				1,159,215
Gross Amount Carried at End of Period	3,207,358			3,207,358
Accumulated Depreciation	326,128			326,128
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,207,358
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	326,128
Operating Properties [Member] | 12641 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,766,822
Initial Cost of Buildings				2,539,214
Costs Capitalized Subsequent to Acquisition				132,812
Land and Improvements				3,766,822
Building and Improvements				2,672,026
Gross Amount Carried at End of Period	6,438,848			6,438,848
Accumulated Depreciation	496,032			496,032
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,438,848
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	496,032
Operating Properties [Member] | 12681-12691 Pala Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,221,102
Initial Cost of Buildings				3,225,596
Costs Capitalized Subsequent to Acquisition				91,960
Land and Improvements				5,220,148
Building and Improvements				3,318,510
Gross Amount Carried at End of Period	8,538,658			8,538,658
Accumulated Depreciation	458,102			458,102
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,538,658
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	458,102
Operating Properties [Member] | 1720 West 135th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,423,389
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				13,111,573
Land and Improvements				7,427,353
Building and Improvements				13,107,609
Gross Amount Carried at End of Period	20,534,962			20,534,962
Accumulated Depreciation	315,243			315,243
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,534,962
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	315,243
Operating Properties [Member] | 850 S Jupiter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				799,707
Initial Cost of Buildings				6,122,065
Costs Capitalized Subsequent to Acquisition				525,135
Land and Improvements				799,707
Building and Improvements				6,647,200
Gross Amount Carried at End of Period	7,446,907			7,446,907
Accumulated Depreciation	1,228,448			1,228,448
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,446,907
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,228,448
Operating Properties [Member] | 2510 W Main Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,785,741
Initial Cost of Buildings				11,158,818
Costs Capitalized Subsequent to Acquisition				2,350,115
Land and Improvements				1,785,741
Building and Improvements				13,508,933
Gross Amount Carried at End of Period	15,294,674			15,294,674
Accumulated Depreciation	2,629,047			2,629,047
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,294,674
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,629,047
Operating Properties [Member] | 4251 North Highway 121 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,165,780
Initial Cost of Buildings				7,799,270
Costs Capitalized Subsequent to Acquisition				422,213
Land and Improvements				1,165,780
Building and Improvements				8,221,482
Gross Amount Carried at End of Period	9,387,262			9,387,262
Accumulated Depreciation	1,615,287			1,615,287
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,387,262
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,615,287
Operating Properties [Member] | 1150 Pleasant Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,547,811
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				14,343,114
Land and Improvements				3,712,683
Building and Improvements				12,178,242
Gross Amount Carried at End of Period	15,890,925			15,890,925
Accumulated Depreciation	3,249,276			3,249,276
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,890,925
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,249,276
Operating Properties [Member] | 25 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				288,823
Initial Cost of Buildings				3,441,512
Costs Capitalized Subsequent to Acquisition				174,541
Land and Improvements				288,823
Building and Improvements				3,616,053
Gross Amount Carried at End of Period	3,904,876			3,904,876
Accumulated Depreciation	492,665			492,665
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,904,876
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	492,665
Operating Properties [Member] | 45 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				818,114
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,789,031
Land and Improvements				825,529
Building and Improvements				4,781,616
Gross Amount Carried at End of Period	5,607,145			5,607,145
Accumulated Depreciation	1,415,767			1,415,767
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,607,145
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,415,767
Operating Properties [Member] | 2011 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				223,702
Initial Cost of Buildings				3,574,142
Costs Capitalized Subsequent to Acquisition				397,081
Land and Improvements				223,702
Building and Improvements				3,971,223
Gross Amount Carried at End of Period	4,194,925			4,194,925
Accumulated Depreciation	816,565			816,565
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,194,925
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	816,565
Operating Properties [Member] | 2121 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				272,823
Initial Cost of Buildings				3,606,920
Costs Capitalized Subsequent to Acquisition				439,628
Land and Improvements				272,823
Building and Improvements				4,046,549
Gross Amount Carried at End of Period	4,319,372			4,319,372
Accumulated Depreciation	1,042,735			1,042,735
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,319,372
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,042,735
Operating Properties [Member] | 800 Commerce Parkway West Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,374,664
Initial Cost of Buildings				29,963,830
Costs Capitalized Subsequent to Acquisition				1,822,379
Land and Improvements				1,374,664
Building and Improvements				31,786,209
Gross Amount Carried at End of Period	33,160,873			33,160,873
Accumulated Depreciation	5,435,338			5,435,338
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	33,160,873
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,435,338
Operating Properties [Member] | 110 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				555,549
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,559,671
Land and Improvements				1,241,531
Building and Improvements				5,873,689
Gross Amount Carried at End of Period	7,115,220			7,115,220
Accumulated Depreciation	617,188			617,188
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,115,220
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	617,188
Operating Properties [Member] | 120 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,243,100
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,603,075
Land and Improvements				1,255,751
Building and Improvements				6,590,424
Gross Amount Carried at End of Period	7,846,175			7,846,175
Accumulated Depreciation	775,442			775,442
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,846,175
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	775,442
Operating Properties [Member] | 130 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,171,160
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,045,014
Land and Improvements				1,183,811
Building and Improvements				6,032,363
Gross Amount Carried at End of Period	7,216,174			7,216,174
Accumulated Depreciation	516,768			516,768
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,216,174
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	516,768
Operating Properties [Member] | 140 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,243,100
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,460,294
Land and Improvements				1,255,751
Building and Improvements				6,447,643
Gross Amount Carried at End of Period	7,703,394			7,703,394
Accumulated Depreciation	794,243			794,243
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,703,394
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	794,243
Operating Properties [Member] | 2988 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,271,948
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,597,878
Land and Improvements				2,095,033
Building and Improvements				6,774,793
Gross Amount Carried at End of Period	8,869,826			8,869,826
Accumulated Depreciation	230,529			230,529
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,869,826
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	230,529
Operating Properties [Member] | 125 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				464,237
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,839,813
Land and Improvements				1,311,956
Building and Improvements				4,992,094
Gross Amount Carried at End of Period	6,304,050			6,304,050
Accumulated Depreciation	1,273,039			1,273,039
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,304,050
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,273,039
Operating Properties [Member] | 2727 London Groveport Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,875,607
Initial Cost of Buildings				11,937,935
Costs Capitalized Subsequent to Acquisition				3,165,643
Land and Improvements				1,875,607
Building and Improvements				15,103,578
Gross Amount Carried at End of Period	16,979,185			16,979,185
Accumulated Depreciation	2,654,726			2,654,726
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,979,185
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,654,726
Operating Properties [Member] | 11835 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				14,121,622
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				23,034,177
Land and Improvements				14,121,622
Building and Improvements				23,034,177
Gross Amount Carried at End of Period	37,155,799			37,155,799
Accumulated Depreciation	2,843,048			2,843,048
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	37,155,799
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,843,048
Operating Properties [Member] | 11841 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,356,207
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				30,724,476
Land and Improvements				9,741,685
Building and Improvements				24,338,998
Gross Amount Carried at End of Period	34,080,683			34,080,683
Accumulated Depreciation	7,316,216			7,316,216
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	34,080,683
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,316,216
Operating Properties [Member] | 1560 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,639,734
Initial Cost of Buildings				12,310,741
Costs Capitalized Subsequent to Acquisition				1,073,860
Land and Improvements				2,639,734
Building and Improvements				13,384,601
Gross Amount Carried at End of Period	16,024,335			16,024,335
Accumulated Depreciation	2,332,845			2,332,845
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,024,335
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,332,845
Operating Properties [Member] | 1575 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,293,284
Initial Cost of Buildings				17,235,926
Costs Capitalized Subsequent to Acquisition				1,200,560
Land and Improvements				3,293,284
Building and Improvements				18,436,486
Gross Amount Carried at End of Period	21,729,770			21,729,770
Accumulated Depreciation	3,102,059			3,102,059
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,729,770
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,102,059
Operating Properties [Member] | 7361 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,245,187
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,667,649
Land and Improvements				3,822,710
Building and Improvements				8,090,126
Gross Amount Carried at End of Period	11,912,836			11,912,836
Accumulated Depreciation	1,974,018			1,974,018
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,912,836
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,974,018
Operating Properties [Member] | 7460 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,785,446
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,144,397
Land and Improvements				3,796,023
Building and Improvements				8,133,820
Gross Amount Carried at End of Period	11,929,843			11,929,843
Accumulated Depreciation	868,037			868,037
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,929,843
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	868,037
Operating Properties [Member] | 7462 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,059,337
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,490,949
Land and Improvements				4,070,629
Building and Improvements				7,479,657
Gross Amount Carried at End of Period	11,550,286			11,550,286
Accumulated Depreciation	699,111			699,111
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,550,286
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	699,111
Operating Properties [Member] | 500 McCarthy Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,194,872
Initial Cost of Buildings				19,991,436
Costs Capitalized Subsequent to Acquisition				5,018,136
Land and Improvements				5,687,013
Building and Improvements				24,517,431
Gross Amount Carried at End of Period	30,204,444			30,204,444
Accumulated Depreciation	9,708,214			9,708,214
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	30,204,444
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	9,708,214
Operating Properties [Member] | 600 Industrial Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,743,800
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				28,146,140
Land and Improvements				9,368,557
Building and Improvements				26,521,383
Gross Amount Carried at End of Period	35,889,940			35,889,940
Accumulated Depreciation	8,493,295			8,493,295
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	35,889,940
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,493,295
Operating Properties [Member] | 7195 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				464,534
Initial Cost of Buildings				6,066,272
Costs Capitalized Subsequent to Acquisition				237,152
Land and Improvements				464,534
Building and Improvements				6,303,424
Gross Amount Carried at End of Period	6,767,958			6,767,958
Accumulated Depreciation	998,330			998,330
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,767,958
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	998,330
Operating Properties [Member] | 7253 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				954,130
Initial Cost of Buildings				10,585,367
Costs Capitalized Subsequent to Acquisition				544,460
Land and Improvements				954,130
Building and Improvements				11,129,827
Gross Amount Carried at End of Period	12,083,957			12,083,957
Accumulated Depreciation	1,792,344			1,792,344
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,083,957
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,792,344
Operating Properties [Member] | 12537 Cerise Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,203,194
Initial Cost of Buildings				5,758,809
Costs Capitalized Subsequent to Acquisition				1,481,588
Land and Improvements				2,203,194
Building and Improvements				7,240,397
Gross Amount Carried at End of Period	9,443,591			9,443,591
Accumulated Depreciation	973,565			973,565
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,443,591
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	973,565
Operating Properties [Member] | 1010 Petersburg Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				305,471
Initial Cost of Buildings				5,434,505
Costs Capitalized Subsequent to Acquisition				(819,916)
Land and Improvements				305,471
Building and Improvements				4,614,589
Gross Amount Carried at End of Period	4,920,060			4,920,060
Accumulated Depreciation	817,398			817,398
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,920,060
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	817,398
Operating Properties [Member] | 785 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				401,410
Initial Cost of Buildings				3,087,899
Costs Capitalized Subsequent to Acquisition				437,960
Land and Improvements				401,410
Building and Improvements				3,525,859
Gross Amount Carried at End of Period	3,927,269			3,927,269
Accumulated Depreciation	705,925			705,925
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,927,269
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	705,925
Operating Properties [Member] | 805 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				292,096
Initial Cost of Buildings				2,502,486
Costs Capitalized Subsequent to Acquisition				163,618
Land and Improvements				292,096
Building and Improvements				2,666,103
Gross Amount Carried at End of Period	2,958,199			2,958,199
Accumulated Depreciation	547,438			547,438
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,958,199
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	547,438
Operating Properties [Member] | 825 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				370,149
Initial Cost of Buildings				3,095,116
Costs Capitalized Subsequent to Acquisition				442,314
Land and Improvements				370,149
Building and Improvements				3,537,431
Gross Amount Carried at End of Period	3,907,580			3,907,580
Accumulated Depreciation	721,514			721,514
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,907,580
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	721,514
Operating Properties [Member] | 845 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				444,318
Initial Cost of Buildings				3,811,889
Costs Capitalized Subsequent to Acquisition				399,366
Land and Improvements				444,318
Building and Improvements				4,211,255
Gross Amount Carried at End of Period	4,655,573			4,655,573
Accumulated Depreciation	814,352			814,352
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,655,573
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	814,352
Operating Properties [Member] | 4198 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				94,274
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,288,127
Land and Improvements				791,880
Building and Improvements				5,590,521
Gross Amount Carried at End of Period	6,382,401			6,382,401
Accumulated Depreciation	1,783,401			1,783,401
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,382,401
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,783,401
Operating Properties [Member] | 4183 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				122,203
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,214,675
Land and Improvements				526,266
Building and Improvements				2,810,612
Gross Amount Carried at End of Period	3,336,878			3,336,878
Accumulated Depreciation	1,406,053			1,406,053
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,336,878
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,406,053
Operating Properties [Member] | 4189 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				100,106
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,582,494
Land and Improvements				431,106
Building and Improvements				3,251,494
Gross Amount Carried at End of Period	3,682,600			3,682,600
Accumulated Depreciation	1,568,325			1,568,325
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,682,600
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,568,325
Operating Properties [Member] | 4193 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				107,586
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,522,376
Land and Improvements				505,700
Building and Improvements				3,124,262
Gross Amount Carried at End of Period	3,629,962			3,629,962
Accumulated Depreciation	970,547			970,547
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,629,962
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	970,547
Operating Properties [Member] | 4328, 4336 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				521,122
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,531,390
Land and Improvements				825,092
Building and Improvements				5,227,420
Gross Amount Carried at End of Period	6,052,512			6,052,512
Accumulated Depreciation	2,697,862			2,697,862
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,052,512
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,697,862
Operating Properties [Member] | 4344 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				484,001
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,185,404
Land and Improvements				173,623
Building and Improvements				3,495,782
Gross Amount Carried at End of Period	3,669,405			3,669,405
Accumulated Depreciation	1,967,845			1,967,845
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,669,405
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,967,845
Operating Properties [Member] | 4380 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				282,996
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,209,513
Land and Improvements				283,368
Building and Improvements				2,209,141
Gross Amount Carried at End of Period	2,492,509			2,492,509
Accumulated Depreciation	1,273,523			1,273,523
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,492,509
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,273,523
Operating Properties [Member] | 4388 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				143,661
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,214,707
Land and Improvements				132,655
Building and Improvements				1,225,713
Gross Amount Carried at End of Period	1,358,368			1,358,368
Accumulated Depreciation	694,546			694,546
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,358,368
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	694,546
Operating Properties [Member] | 4475 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				748,693
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,918,129
Land and Improvements				1,525,421
Building and Improvements				6,141,401
Gross Amount Carried at End of Period	7,666,822			7,666,822
Accumulated Depreciation	1,581,382			1,581,382
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,666,822
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,581,382
Operating Properties [Member] | 4485 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,827,595
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,509,786
Land and Improvements				1,827,595
Building and Improvements				6,509,786
Gross Amount Carried at End of Period	8,337,381			8,337,381
Accumulated Depreciation	375,031			375,031
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,337,381
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	375,031
Operating Properties [Member] | 4500 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				230,622
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,878,225
Land and Improvements				231,692
Building and Improvements				2,877,155
Gross Amount Carried at End of Period	3,108,847			3,108,847
Accumulated Depreciation	1,721,076			1,721,076
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,108,847
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,721,076
Operating Properties [Member] | 4501 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				319,289
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,941,886
Land and Improvements				320,450
Building and Improvements				2,940,725
Gross Amount Carried at End of Period	3,261,175			3,261,175
Accumulated Depreciation	1,891,827			1,891,827
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,261,175
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,891,827
Operating Properties [Member] | 4523 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				234,564
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,319,067
Land and Improvements				235,698
Building and Improvements				3,317,933
Gross Amount Carried at End of Period	3,553,631			3,553,631
Accumulated Depreciation	2,339,202			2,339,202
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,553,631
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,339,202
Operating Properties [Member] | 4524 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				182,810
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,848,066
Land and Improvements				183,888
Building and Improvements				2,846,988
Gross Amount Carried at End of Period	3,030,876			3,030,876
Accumulated Depreciation	1,912,071			1,912,071
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,030,876
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,912,071
Operating Properties [Member] | Unit 5 Logix Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances
Initial Cost of Land				10,547,677
Initial Cost of Buildings				29,691,911
Costs Capitalized Subsequent to Acquisition				(9,562,316)
Land and Improvements				8,128,152
Building and Improvements				22,549,120
Gross Amount Carried at End of Period	30,677,272			30,677,272
Accumulated Depreciation	3,504,963			3,504,963
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	30,677,272
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,504,963
Operating Properties [Member] | 1000 South Loop West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				509,351
Initial Cost of Buildings				3,549,504
Costs Capitalized Subsequent to Acquisition				994,350
Land and Improvements				509,351
Building and Improvements				4,543,854
Gross Amount Carried at End of Period	5,053,205			5,053,205
Accumulated Depreciation	993,896			993,896
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,053,205
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	993,896
Operating Properties [Member] | 10241 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				558,491
Initial Cost of Buildings				5,740,552
Costs Capitalized Subsequent to Acquisition				138,801
Land and Improvements				558,491
Building and Improvements				5,879,353
Gross Amount Carried at End of Period	6,437,844			6,437,844
Accumulated Depreciation	924,356			924,356
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,437,844
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	924,356
Operating Properties [Member] | 10245 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				426,927
Initial Cost of Buildings				3,460,513
Costs Capitalized Subsequent to Acquisition				525,045
Land and Improvements				426,927
Building and Improvements				3,985,558
Gross Amount Carried at End of Period	4,412,485			4,412,485
Accumulated Depreciation	934,656			934,656
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,412,485
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	934,656
Operating Properties [Member] | 10301 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				545,501
Initial Cost of Buildings				2,927,700
Costs Capitalized Subsequent to Acquisition				1,418,126
Land and Improvements				545,501
Building and Improvements				4,345,825
Gross Amount Carried at End of Period	4,891,326			4,891,326
Accumulated Depreciation	723,469			723,469
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,891,326
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	723,469
Operating Properties [Member] | 10305 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,340,609
Initial Cost of Buildings				7,489,720
Costs Capitalized Subsequent to Acquisition				3,263,257
Land and Improvements				1,340,609
Building and Improvements				10,752,976
Gross Amount Carried at End of Period	12,093,585			12,093,585
Accumulated Depreciation	2,762,324			2,762,324
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,093,585
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,762,324
Operating Properties [Member] | 1050 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				973,482
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,531,502
Land and Improvements				992,093
Building and Improvements				3,512,891
Gross Amount Carried at End of Period	4,504,984			4,504,984
Accumulated Depreciation	375,462			375,462
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,504,984
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	375,462
Operating Properties [Member] | 10607 Haddington Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				201,469
Initial Cost of Buildings				1,631,561
Costs Capitalized Subsequent to Acquisition				160,347
Land and Improvements				201,469
Building and Improvements				1,791,909
Gross Amount Carried at End of Period	1,993,378			1,993,378
Accumulated Depreciation	345,323			345,323
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,993,378
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	345,323
Operating Properties [Member] | 10735 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,110,988
Initial Cost of Buildings				6,351,946
Costs Capitalized Subsequent to Acquisition				3,158,530
Land and Improvements				1,135,483
Building and Improvements				9,485,981
Gross Amount Carried at End of Period	10,621,464			10,621,464
Accumulated Depreciation	3,706,395			3,706,395
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,621,464
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,706,395
Operating Properties [Member] | 10739 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				797,931
Initial Cost of Buildings				5,950,894
Costs Capitalized Subsequent to Acquisition				476,655
Land and Improvements				799,560
Building and Improvements				6,425,920
Gross Amount Carried at End of Period	7,225,480			7,225,480
Accumulated Depreciation	2,606,566			2,606,566
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,225,480
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,606,566
Operating Properties [Member] | 11201 Greens Crossing Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,006,194
Initial Cost of Buildings				5,412,584
Costs Capitalized Subsequent to Acquisition				2,619,384
Land and Improvements				1,008,542
Building and Improvements				8,029,620
Gross Amount Carried at End of Period	9,038,162			9,038,162
Accumulated Depreciation	2,712,516			2,712,516
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,038,162
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,712,516
Operating Properties [Member] | 11220 Ella Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,505,855
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,073,136
Land and Improvements				1,534,644
Building and Improvements				8,044,347
Gross Amount Carried at End of Period	9,578,991			9,578,991
Accumulated Depreciation	734,400			734,400
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,578,991
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	734,400
Operating Properties [Member] | 1283 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				80,730
Initial Cost of Buildings				870,656
Costs Capitalized Subsequent to Acquisition				146,624
Land and Improvements				80,730
Building and Improvements				1,017,280
Gross Amount Carried at End of Period	1,098,010			1,098,010
Accumulated Depreciation	228,608			228,608
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,098,010
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	228,608
Operating Properties [Member] | 1287 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				146,654
Initial Cost of Buildings				1,620,780
Costs Capitalized Subsequent to Acquisition				63,282
Land and Improvements				146,654
Building and Improvements				1,684,061
Gross Amount Carried at End of Period	1,830,715			1,830,715
Accumulated Depreciation	334,126			334,126
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,830,715
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	334,126
Operating Properties [Member] | 1291 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				510,102
Initial Cost of Buildings				4,129,042
Costs Capitalized Subsequent to Acquisition				602,376
Land and Improvements				510,102
Building and Improvements				4,731,418
Gross Amount Carried at End of Period	5,241,520			5,241,520
Accumulated Depreciation	938,895			938,895
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,241,520
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	938,895
Operating Properties [Member] | 1416 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				218,850
Initial Cost of Buildings				1,639,902
Costs Capitalized Subsequent to Acquisition				569,056
Land and Improvements				218,850
Building and Improvements				2,208,957
Gross Amount Carried at End of Period	2,427,807			2,427,807
Accumulated Depreciation	517,674			517,674
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,427,807
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	517,674
Operating Properties [Member] | 1420 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				211,279
Initial Cost of Buildings				1,554,156
Costs Capitalized Subsequent to Acquisition				291,238
Land and Improvements				211,279
Building and Improvements				1,845,394
Gross Amount Carried at End of Period	2,056,673			2,056,673
Accumulated Depreciation	308,944			308,944
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,056,673
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	308,944
Operating Properties [Member] | 14200 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,396,794
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,960,165
Land and Improvements				1,699,632
Building and Improvements				4,657,327
Gross Amount Carried at End of Period	6,356,959			6,356,959
Accumulated Depreciation	792,722			792,722
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,356,959
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	792,722
Operating Properties [Member] | 1424 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				283,107
Initial Cost of Buildings				2,077,323
Costs Capitalized Subsequent to Acquisition				423,815
Land and Improvements				283,107
Building and Improvements				2,501,138
Gross Amount Carried at End of Period	2,784,245			2,784,245
Accumulated Depreciation	488,242			488,242
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,784,245
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	488,242
Operating Properties [Member] | 1428 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				367,446
Initial Cost of Buildings				1,952,453
Costs Capitalized Subsequent to Acquisition				464,576
Land and Improvements				367,446
Building and Improvements				2,417,028
Gross Amount Carried at End of Period	2,784,474			2,784,474
Accumulated Depreciation	450,680			450,680
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,784,474
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	450,680
Operating Properties [Member] | 14300 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,377,193
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,613,585
Land and Improvements				1,388,292
Building and Improvements				5,602,486
Gross Amount Carried at End of Period	6,990,778			6,990,778
Accumulated Depreciation	850,061			850,061
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,990,778
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	850,061
Operating Properties [Member] | 14400 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,830,419
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,162,866
Land and Improvements				1,838,166
Building and Improvements				7,155,119
Gross Amount Carried at End of Period	8,993,285			8,993,285
Accumulated Depreciation	2,203,839			2,203,839
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,993,285
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,203,839
Operating Properties [Member] | 15102 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				755,121
Initial Cost of Buildings				3,155,774
Costs Capitalized Subsequent to Acquisition				249,394
Land and Improvements				755,121
Building and Improvements				3,405,168
Gross Amount Carried at End of Period	4,160,289			4,160,289
Accumulated Depreciation	661,680			661,680
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,160,289
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	661,680
Operating Properties [Member] | 15150 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				418,580
Initial Cost of Buildings				1,564,587
Costs Capitalized Subsequent to Acquisition				264,824
Land and Improvements				418,580
Building and Improvements				1,829,411
Gross Amount Carried at End of Period	2,247,991			2,247,991
Accumulated Depreciation	391,559			391,559
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,247,991
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	391,559
Operating Properties [Member] | 16330 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,540,109
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,519,116
Land and Improvements				1,966,472
Building and Improvements				8,092,753
Gross Amount Carried at End of Period	10,059,225			10,059,225
Accumulated Depreciation	1,011,409			1,011,409
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,059,225
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,011,409
Operating Properties [Member] | 16405 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				438,853
Initial Cost of Buildings				3,030,396
Costs Capitalized Subsequent to Acquisition				1,194,986
Land and Improvements				438,853
Building and Improvements				4,225,382
Gross Amount Carried at End of Period	4,664,235			4,664,235
Accumulated Depreciation	2,053,640			2,053,640
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,664,235
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,053,640
Operating Properties [Member] | 16420 West Hardy Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				529,876
Initial Cost of Buildings				3,267,872
Costs Capitalized Subsequent to Acquisition				374,162
Land and Improvements				529,876
Building and Improvements				3,642,034
Gross Amount Carried at End of Period	4,171,910			4,171,910
Accumulated Depreciation	701,597			701,597
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,171,910
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	701,597
Operating Properties [Member] | 16445 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				363,339
Initial Cost of Buildings				2,509,186
Costs Capitalized Subsequent to Acquisition				325,072
Land and Improvements				363,339
Building and Improvements				2,834,258
Gross Amount Carried at End of Period	3,197,597			3,197,597
Accumulated Depreciation	1,436,619			1,436,619
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,197,597
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,436,619
Operating Properties [Member] | 1646 Rankin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				329,961
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,033,129
Land and Improvements				592,234
Building and Improvements				4,770,856
Gross Amount Carried at End of Period	5,363,090			5,363,090
Accumulated Depreciation	1,690,069			1,690,069
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,363,090
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,690,069
Operating Properties [Member] | 1655 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				197,226
Initial Cost of Buildings				935,036
Costs Capitalized Subsequent to Acquisition				566,781
Land and Improvements				197,226
Building and Improvements				1,501,817
Gross Amount Carried at End of Period	1,699,043			1,699,043
Accumulated Depreciation	420,556			420,556
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,699,043
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	420,556
Operating Properties [Member] | 16580 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				289,000
Initial Cost of Buildings				3,559,857
Costs Capitalized Subsequent to Acquisition				1,325,263
Land and Improvements				289,000
Building and Improvements				4,885,121
Gross Amount Carried at End of Period	5,174,121			5,174,121
Accumulated Depreciation	2,243,816			2,243,816
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,174,121
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,243,816
Operating Properties [Member] | 16602 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				284,403
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,462,498
Land and Improvements				503,779
Building and Improvements				5,243,122
Gross Amount Carried at End of Period	5,746,901			5,746,901
Accumulated Depreciation	1,824,292			1,824,292
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,746,901
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,824,292
Operating Properties [Member] | 16605 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				298,999
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,423,751
Land and Improvements				496,186
Building and Improvements				3,226,564
Gross Amount Carried at End of Period	3,722,750			3,722,750
Accumulated Depreciation	1,357,158			1,357,158
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,722,750
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,357,158
Operating Properties [Member] | 1665 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				452,439
Initial Cost of Buildings				2,016,585
Costs Capitalized Subsequent to Acquisition				594,268
Land and Improvements				452,439
Building and Improvements				2,610,852
Gross Amount Carried at End of Period	3,063,291			3,063,291
Accumulated Depreciation	462,530			462,530
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,063,291
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	462,530
Operating Properties [Member] | 16680 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				311,952
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,714,116
Land and Improvements				492,869
Building and Improvements				3,533,199
Gross Amount Carried at End of Period	4,026,068			4,026,068
Accumulated Depreciation	957,760			957,760
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,026,068
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	957,760
Operating Properties [Member] | 16685 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				414,691
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,459,178
Land and Improvements				414,691
Building and Improvements				2,459,178
Gross Amount Carried at End of Period	2,873,869			2,873,869
Accumulated Depreciation	884,382			884,382
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,873,869
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	884,382
Operating Properties [Member] | 1755 Trans Central Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				293,534
Initial Cost of Buildings				3,036,269
Costs Capitalized Subsequent to Acquisition				1,476,893
Land and Improvements				306,147
Building and Improvements				4,500,549
Gross Amount Carried at End of Period	4,806,696			4,806,696
Accumulated Depreciation	1,863,536			1,863,536
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,806,696
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,863,536
Operating Properties [Member] | 4301 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				226,973
Initial Cost of Buildings				1,174,979
Costs Capitalized Subsequent to Acquisition				174,177
Land and Improvements				226,973
Building and Improvements				1,349,156
Gross Amount Carried at End of Period	1,576,129			1,576,129
Accumulated Depreciation	349,730			349,730
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,576,129
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	349,730
Operating Properties [Member] | 4401 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				244,240
Initial Cost of Buildings				1,412,622
Costs Capitalized Subsequent to Acquisition				247,951
Land and Improvements				244,240
Building and Improvements				1,660,573
Gross Amount Carried at End of Period	1,904,813			1,904,813
Accumulated Depreciation	397,128			397,128
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,904,813
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	397,128
Operating Properties [Member] | 4501 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				252,907
Initial Cost of Buildings				1,504,053
Costs Capitalized Subsequent to Acquisition				229,239
Land and Improvements				252,907
Building and Improvements				1,733,292
Gross Amount Carried at End of Period	1,986,199			1,986,199
Accumulated Depreciation	291,990			291,990
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,986,199
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	291,990
Operating Properties [Member] | 5200 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,519,458
Initial Cost of Buildings				7,135,548
Costs Capitalized Subsequent to Acquisition				4,015,803
Land and Improvements				1,520,074
Building and Improvements				11,150,735
Gross Amount Carried at End of Period	12,670,809			12,670,809
Accumulated Depreciation	3,864,134			3,864,134
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,670,809
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,864,134
Operating Properties [Member] | 5250 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,173,287
Initial Cost of Buildings				8,868,256
Costs Capitalized Subsequent to Acquisition				3,086,989
Land and Improvements				2,173,942
Building and Improvements				11,954,590
Gross Amount Carried at End of Period	14,128,532			14,128,532
Accumulated Depreciation	3,320,014			3,320,014
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,128,532
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,320,014
Operating Properties [Member] | 5500 N. Sam Houston Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,243,541
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,540,529
Land and Improvements				1,513,152
Building and Improvements				6,270,918
Gross Amount Carried at End of Period	7,784,070			7,784,070
Accumulated Depreciation	1,549,152			1,549,152
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,784,070
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,549,152
Operating Properties [Member] | 8017 Pinemont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				900,953
Initial Cost of Buildings				5,323,727
Costs Capitalized Subsequent to Acquisition				912,329
Land and Improvements				900,953
Building and Improvements				6,236,056
Gross Amount Carried at End of Period	7,137,009			7,137,009
Accumulated Depreciation	973,047			973,047
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,137,009
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	973,047
Operating Properties [Member] | 8272 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				530,494
Initial Cost of Buildings				4,108,626
Costs Capitalized Subsequent to Acquisition				384,828
Land and Improvements				530,494
Building and Improvements				4,493,454
Gross Amount Carried at End of Period	5,023,948			5,023,948
Accumulated Depreciation	818,718			818,718
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,023,948
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	818,718
Operating Properties [Member] | 8282 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				450,422
Initial Cost of Buildings				3,304,942
Costs Capitalized Subsequent to Acquisition				1,139,437
Land and Improvements				450,422
Building and Improvements				4,444,379
Gross Amount Carried at End of Period	4,894,801			4,894,801
Accumulated Depreciation	963,774			963,774
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,894,801
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	963,774
Operating Properties [Member] | 8301 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,515,862
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				26,997,764
Land and Improvements				7,083,514
Building and Improvements				24,430,112
Gross Amount Carried at End of Period	31,513,626			31,513,626
Accumulated Depreciation	6,949,197			6,949,197
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	31,513,626
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	6,949,197
Operating Properties [Member] | 8303 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,613,370
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				15,863,256
Land and Improvements				4,310,317
Building and Improvements				16,166,309
Gross Amount Carried at End of Period	20,476,626			20,476,626
Accumulated Depreciation	1,441,378			1,441,378
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,476,626
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,441,378
Operating Properties [Member] | 850 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,893,405
Initial Cost of Buildings				11,593,197
Costs Capitalized Subsequent to Acquisition				2,996,106
Land and Improvements				2,899,861
Building and Improvements				14,582,846
Gross Amount Carried at End of Period	17,482,707			17,482,707
Accumulated Depreciation	4,188,653			4,188,653
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	17,482,707
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,188,653
Operating Properties [Member] | 860 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,399,365
Initial Cost of Buildings				6,344,650
Costs Capitalized Subsequent to Acquisition				1,542,047
Land and Improvements				1,374,012
Building and Improvements				7,912,050
Gross Amount Carried at End of Period	9,286,062			9,286,062
Accumulated Depreciation	2,149,728			2,149,728
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,286,062
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,149,728
Operating Properties [Member] | 8801-19 & 8821-49 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,290,001
Initial Cost of Buildings				15,297,141
Costs Capitalized Subsequent to Acquisition				4,618,108
Land and Improvements				2,290,002
Building and Improvements				19,915,248
Gross Amount Carried at End of Period	22,205,250			22,205,250
Accumulated Depreciation	7,285,061			7,285,061
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,205,250
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,285,061
Operating Properties [Member] | 8802-8824 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,774,995
Initial Cost of Buildings				6,364,767
Costs Capitalized Subsequent to Acquisition				2,074,557
Land and Improvements				2,775,021
Building and Improvements				8,439,297
Gross Amount Carried at End of Period	11,214,318			11,214,318
Accumulated Depreciation	2,926,974			2,926,974
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,214,318
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,926,974
Operating Properties [Member] | 8825-8839 N Sam Houston Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				638,453
Initial Cost of Buildings				3,258,815
Costs Capitalized Subsequent to Acquisition				816,626
Land and Improvements				638,477
Building and Improvements				4,075,416
Gross Amount Carried at End of Period	4,713,893			4,713,893
Accumulated Depreciation	1,591,430			1,591,430
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,713,893
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,591,430
Operating Properties [Member] | 8850-8872 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				504,317
Initial Cost of Buildings				2,878,351
Costs Capitalized Subsequent to Acquisition				1,932,869
Land and Improvements				504,341
Building and Improvements				4,811,196
Gross Amount Carried at End of Period	5,315,537			5,315,537
Accumulated Depreciation	1,938,527			1,938,527
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,315,537
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,938,527
Operating Properties [Member] | 16200 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,748,348
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,341,500
Land and Improvements				2,120,319
Building and Improvements				8,969,529
Gross Amount Carried at End of Period	11,089,848			11,089,848
Accumulated Depreciation	1,677,897			1,677,897
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,089,848
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,677,897
Operating Properties [Member] | 5430 FAA Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,245,346
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,718,442
Land and Improvements				3,198,031
Building and Improvements				10,765,757
Gross Amount Carried at End of Period	13,963,788			13,963,788
Accumulated Depreciation	406,660			406,660
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,963,788
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	406,660
Operating Properties [Member] | 951 Valleyview Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,899,824
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				14,197,000
Land and Improvements				5,554,903
Building and Improvements				12,541,921
Gross Amount Carried at End of Period	18,096,824			18,096,824
Accumulated Depreciation	539,219			539,219
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	18,096,824
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	539,219
Operating Properties [Member] | Cabot III UK1B01 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,888,058
Initial Cost of Buildings				35,003,668
Costs Capitalized Subsequent to Acquisition				(10,913,850)
Land and Improvements				9,161,064
Building and Improvements				26,816,812
Gross Amount Carried at End of Period	35,977,876			35,977,876
Accumulated Depreciation	3,996,861			3,996,861
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	35,977,876
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,996,861
Operating Properties [Member] | 1011 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				842,043
Initial Cost of Buildings				984,087
Costs Capitalized Subsequent to Acquisition				205,986
Land and Improvements				842,043
Building and Improvements				1,190,073
Gross Amount Carried at End of Period	2,032,116			2,032,116
Accumulated Depreciation	240,394			240,394
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,032,116
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	240,394
Operating Properties [Member] | 1035 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				875,172
Initial Cost of Buildings				2,071,051
Costs Capitalized Subsequent to Acquisition				124,976
Land and Improvements				875,172
Building and Improvements				2,196,028
Gross Amount Carried at End of Period	3,071,200			3,071,200
Accumulated Depreciation	369,876			369,876
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,071,200
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	369,876
Operating Properties [Member] | 1549 W Glenlake Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,339,627
Initial Cost of Buildings				3,763,288
Costs Capitalized Subsequent to Acquisition				203,472
Land and Improvements				1,339,627
Building and Improvements				3,966,759
Gross Amount Carried at End of Period	5,306,386			5,306,386
Accumulated Depreciation	673,782			673,782
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,306,386
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	673,782
Operating Properties [Member] | 901 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				866,378
Initial Cost of Buildings				2,112,616
Costs Capitalized Subsequent to Acquisition				47,808
Land and Improvements				866,378
Building and Improvements				2,160,424
Gross Amount Carried at End of Period	3,026,802			3,026,802
Accumulated Depreciation	331,220			331,220
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,026,802
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	331,220
Operating Properties [Member] | 925 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				945,251
Initial Cost of Buildings				2,010,181
Costs Capitalized Subsequent to Acquisition				177,500
Land and Improvements				945,251
Building and Improvements				2,187,681
Gross Amount Carried at End of Period	3,132,932			3,132,932
Accumulated Depreciation	308,760			308,760
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,132,932
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	308,760
Operating Properties [Member] | 8241 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,246,618
Initial Cost of Buildings				6,844,393
Costs Capitalized Subsequent to Acquisition				1,445,551
Land and Improvements				1,246,618
Building and Improvements				8,289,943
Gross Amount Carried at End of Period	9,536,561			9,536,561
Accumulated Depreciation	1,324,901			1,324,901
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,536,561
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,324,901
Operating Properties [Member] | 8242 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,488,746
Initial Cost of Buildings				9,072,440
Costs Capitalized Subsequent to Acquisition				1,536,444
Land and Improvements				1,488,746
Building and Improvements				10,608,884
Gross Amount Carried at End of Period	12,097,630			12,097,630
Accumulated Depreciation	1,928,648			1,928,648
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,097,630
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,928,648
Operating Properties [Member] | 8246 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				590,922
Initial Cost of Buildings				3,374,522
Costs Capitalized Subsequent to Acquisition				478,590
Land and Improvements				590,922
Building and Improvements				3,853,112
Gross Amount Carried at End of Period	4,444,034			4,444,034
Accumulated Depreciation	575,919			575,919
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,444,034
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	575,919
Operating Properties [Member] | 19 Crows Mill Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				41,975,226
Land and Improvements				25,067,669
Building and Improvements				16,907,557
Gross Amount Carried at End of Period	41,975,226			41,975,226
Accumulated Depreciation	125,138			125,138
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	41,975,226
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	125,138
Operating Properties [Member] | 1305 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				808,159
Initial Cost of Buildings				5,712,959
Costs Capitalized Subsequent to Acquisition				1,127,506
Land and Improvements				808,159
Building and Improvements				6,840,465
Gross Amount Carried at End of Period	7,648,624			7,648,624
Accumulated Depreciation	1,443,791			1,443,791
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,648,624
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,443,791
Operating Properties [Member] | 1325 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,612,924
Initial Cost of Buildings				9,771,680
Costs Capitalized Subsequent to Acquisition				1,628,006
Land and Improvements				1,612,924
Building and Improvements				11,399,686
Gross Amount Carried at End of Period	13,012,610			13,012,610
Accumulated Depreciation	2,615,845			2,615,845
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,012,610
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,615,845
Operating Properties [Member] | 3600 Cobb International Bld NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				716,860
Initial Cost of Buildings				6,962,212
Costs Capitalized Subsequent to Acquisition				661,332
Land and Improvements				716,860
Building and Improvements				7,623,545
Gross Amount Carried at End of Period	8,340,405			8,340,405
Accumulated Depreciation	1,438,570			1,438,570
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,340,405
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,438,570
Operating Properties [Member] | Unit 1 Bear Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances
Initial Cost of Land				10,849,890
Initial Cost of Buildings				36,219,855
Costs Capitalized Subsequent to Acquisition				(11,021,038)
Land and Improvements				8,361,041
Building and Improvements				27,687,666
Gross Amount Carried at End of Period	36,048,707			36,048,707
Accumulated Depreciation	4,172,348			4,172,348
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	36,048,707
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,172,348
Operating Properties [Member] | 650 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				464,382
Initial Cost of Buildings				6,722,830
Costs Capitalized Subsequent to Acquisition				16,054,002
Land and Improvements				830,779
Building and Improvements				22,410,435
Gross Amount Carried at End of Period	23,241,214			23,241,214
Accumulated Depreciation	4,237,198			4,237,198
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	23,241,214
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,237,198
Operating Properties [Member] | 680 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				952,361
Initial Cost of Buildings				6,722,830
Costs Capitalized Subsequent to Acquisition				7,217,277
Land and Improvements				952,361
Building and Improvements				13,940,107
Gross Amount Carried at End of Period	14,892,468			14,892,468
Accumulated Depreciation	8,178,680			8,178,680
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,892,468
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,178,680
Operating Properties [Member] | 1770 Interstate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				650,000
Initial Cost of Buildings				5,444,220
Costs Capitalized Subsequent to Acquisition				0
Land and Improvements				650,000
Building and Improvements				5,444,220
Gross Amount Carried at End of Period	6,094,220			6,094,220
Accumulated Depreciation	884,333			884,333
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,094,220
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	884,333
Operating Properties [Member] | 1200 Claybrick Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,876,500
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				13,422,075
Land and Improvements				8,329,026
Building and Improvements				11,969,549
Gross Amount Carried at End of Period	20,298,575			20,298,575
Accumulated Depreciation	411,097			411,097
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,298,575
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	411,097
Operating Properties [Member] | 1806 Highway 146th South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,055,035
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,603,062
Land and Improvements				1,055,035
Building and Improvements				8,603,062
Gross Amount Carried at End of Period	9,658,097			9,658,097
Accumulated Depreciation	169,943			169,943
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,658,097
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	169,943
Operating Properties [Member] | 11425 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				975,974
Initial Cost of Buildings				3,409,036
Costs Capitalized Subsequent to Acquisition				100,699
Land and Improvements				977,542
Building and Improvements				3,508,166
Gross Amount Carried at End of Period	4,485,708			4,485,708
Accumulated Depreciation	1,194,423			1,194,423
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,485,708
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,194,423
Operating Properties [Member] | 11503 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,561,931
Initial Cost of Buildings				9,695,493
Costs Capitalized Subsequent to Acquisition				275,721
Land and Improvements				2,566,047
Building and Improvements				9,967,098
Gross Amount Carried at End of Period	12,533,145			12,533,145
Accumulated Depreciation	3,207,609			3,207,609
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,533,145
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,207,609
Operating Properties [Member] | 1701 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,063,262
Initial Cost of Buildings				18,719,368
Costs Capitalized Subsequent to Acquisition				382,127
Land and Improvements				4,063,262
Building and Improvements				19,101,495
Gross Amount Carried at End of Period	23,164,757			23,164,757
Accumulated Depreciation	1,916,139			1,916,139
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	23,164,757
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,916,139
Operating Properties [Member] | 1801 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,794,963
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				24,450,486
Land and Improvements				5,421,262
Building and Improvements				22,824,187
Gross Amount Carried at End of Period	28,245,449			28,245,449
Accumulated Depreciation	625,303			625,303
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	28,245,449
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	625,303
Operating Properties [Member] | 1842 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,226,284
Initial Cost of Buildings				11,976,185
Costs Capitalized Subsequent to Acquisition				36,589
Land and Improvements				2,226,284
Building and Improvements				12,012,773
Gross Amount Carried at End of Period	14,239,057			14,239,057
Accumulated Depreciation	1,260,847			1,260,847
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,239,057
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,260,847
Operating Properties [Member] | 1902 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,369,095
Initial Cost of Buildings				14,119,020
Costs Capitalized Subsequent to Acquisition				0
Land and Improvements				2,369,095
Building and Improvements				14,119,020
Gross Amount Carried at End of Period	16,488,115			16,488,115
Accumulated Depreciation	1,600,934			1,600,934
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,488,115
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,600,934
Operating Properties [Member] | 640 S State Road 39 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,612,787
Initial Cost of Buildings				18,065,552
Costs Capitalized Subsequent to Acquisition				1,616,742
Land and Improvements				1,612,787
Building and Improvements				19,682,294
Gross Amount Carried at End of Period	21,295,081			21,295,081
Accumulated Depreciation	3,570,065			3,570,065
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,295,081
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,570,065
Operating Properties [Member] | 7528 Walker Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				893,441
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,723,661
Land and Improvements				779,330
Building and Improvements				5,837,772
Gross Amount Carried at End of Period	6,617,102			6,617,102
Accumulated Depreciation	2,423,715			2,423,715
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,617,102
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,423,715
Operating Properties [Member] | 8301 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,249,550
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				49,336,083
Land and Improvements				11,254,716
Building and Improvements				49,330,917
Gross Amount Carried at End of Period	60,585,633			60,585,633
Accumulated Depreciation	15,583,663			15,583,663
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	60,585,633
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	15,583,663
Operating Properties [Member] | 8500 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,398,815
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				33,820,841
Land and Improvements				11,355,974
Building and Improvements				28,863,682
Gross Amount Carried at End of Period	40,219,656			40,219,656
Accumulated Depreciation	7,315,151			7,315,151
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	40,219,656
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	7,315,151
Operating Properties [Member] | 875 Maxham Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				445,493
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(445,493)
Land and Improvements				445,493
Building and Improvements				12,497,910
Gross Amount Carried at End of Period	12,943,403			12,943,403
Accumulated Depreciation	103,850			103,850
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,943,403
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	103,850
Operating Properties [Member] | 8742 Congdon Hill Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				22,444,500
Initial Cost of Buildings				20,222,582
Costs Capitalized Subsequent to Acquisition				1,049,581
Land and Improvements				22,444,500
Building and Improvements				21,272,163
Gross Amount Carried at End of Period	43,716,663			43,716,663
Accumulated Depreciation	1,772,720			1,772,720
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	43,716,663
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,772,720
Operating Properties [Member] | 7533 Industrial Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,603,460
Initial Cost of Buildings				18,807,987
Costs Capitalized Subsequent to Acquisition				1,844,916
Land and Improvements				5,603,460
Building and Improvements				20,652,903
Gross Amount Carried at End of Period	26,256,363			26,256,363
Accumulated Depreciation	4,260,071			4,260,071
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	26,256,363
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,260,071
Operating Properties [Member] | 1169 Canton Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,232,219
Initial Cost of Buildings				17,897,326
Costs Capitalized Subsequent to Acquisition				1,103,211
Land and Improvements				1,232,219
Building and Improvements				19,000,537
Gross Amount Carried at End of Period	20,232,756			20,232,756
Accumulated Depreciation	2,958,497			2,958,497
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,232,756
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,958,497
Operating Properties [Member] | 65 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				557,174
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,604,588
Land and Improvements				506,318
Building and Improvements				2,655,444
Gross Amount Carried at End of Period	3,161,762			3,161,762
Accumulated Depreciation	847,177			847,177
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,161,762
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	847,177
Operating Properties [Member] | 75 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				419,731
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,360,647
Land and Improvements				430,909
Building and Improvements				2,349,469
Gross Amount Carried at End of Period	2,780,378			2,780,378
Accumulated Depreciation	872,047			872,047
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,780,378
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	872,047
Operating Properties [Member] | 126-132 Liberty Industrial Pkw [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				600,666
Initial Cost of Buildings				4,184,131
Costs Capitalized Subsequent to Acquisition				1,141,035
Land and Improvements				600,666
Building and Improvements				5,325,165
Gross Amount Carried at End of Period	5,925,831			5,925,831
Accumulated Depreciation	1,221,974			1,221,974
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,925,831
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,221,974
Operating Properties [Member] | 95-115 Liberty Industrial Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				660,420
Initial Cost of Buildings				4,785,127
Costs Capitalized Subsequent to Acquisition				1,953,184
Land and Improvements				660,420
Building and Improvements				6,738,311
Gross Amount Carried at End of Period	7,398,731			7,398,731
Accumulated Depreciation	1,305,224			1,305,224
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,398,731
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,305,224
Operating Properties [Member] | 11150 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,627,899
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,262,772
Land and Improvements				6,627,899
Building and Improvements				12,262,772
Gross Amount Carried at End of Period	18,890,671			18,890,671
Accumulated Depreciation	944,453			944,453
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	18,890,671
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	944,453
Operating Properties [Member] | 11250 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,798,886
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,225,467
Land and Improvements				4,798,886
Building and Improvements				9,225,467
Gross Amount Carried at End of Period	14,024,353			14,024,353
Accumulated Depreciation	674,485			674,485
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,024,353
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	674,485
Operating Properties [Member] | 11401 NW 134th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,558,619
Initial Cost of Buildings				17,678,237
Costs Capitalized Subsequent to Acquisition				1,055,318
Land and Improvements				5,558,619
Building and Improvements				18,733,555
Gross Amount Carried at End of Period	24,292,174			24,292,174
Accumulated Depreciation	3,356,484			3,356,484
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	24,292,174
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,356,484
Operating Properties [Member] | 11450 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,623,293
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,366,498
Land and Improvements				3,919,238
Building and Improvements				9,070,553
Gross Amount Carried at End of Period	12,989,791			12,989,791
Accumulated Depreciation	918,910			918,910
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,989,791
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	918,910
Operating Properties [Member] | 8801 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				23,016,646
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				14,966,354
Land and Improvements				37,983,000
Building and Improvements				37,213,752
Gross Amount Carried at End of Period	75,196,752			75,196,752
Accumulated Depreciation	133,104			133,104
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	75,196,752
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	133,104
Operating Properties [Member] | 11440 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,636,564
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				10,784,572
Land and Improvements				5,944,709
Building and Improvements				10,476,427
Gross Amount Carried at End of Period	16,421,136			16,421,136
Accumulated Depreciation	415,013			415,013
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,421,136
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	415,013
Operating Properties [Member] | 456 International Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,862,683
Initial Cost of Buildings				14,357,981
Costs Capitalized Subsequent to Acquisition				4,627,511
Land and Improvements				3,862,683
Building and Improvements				18,985,492
Gross Amount Carried at End of Period	22,848,175			22,848,175
Accumulated Depreciation	3,283,262			3,283,262
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,848,175
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,283,262
Operating Properties [Member] | 21 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,097,170
Initial Cost of Buildings				9,715,401
Costs Capitalized Subsequent to Acquisition				561,745
Land and Improvements				2,097,170
Building and Improvements				10,277,146
Gross Amount Carried at End of Period	12,374,316			12,374,316
Accumulated Depreciation	2,020,602			2,020,602
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,374,316
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,020,602
Operating Properties [Member] | 4 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,263,153
Initial Cost of Buildings				10,261,759
Costs Capitalized Subsequent to Acquisition				893,599
Land and Improvements				2,263,153
Building and Improvements				11,155,358
Gross Amount Carried at End of Period	13,418,511			13,418,511
Accumulated Depreciation	2,062,836			2,062,836
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,418,511
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,062,836
Operating Properties [Member] | 230 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,031,058
Initial Cost of Buildings				2,775,467
Costs Capitalized Subsequent to Acquisition				52,276
Land and Improvements				4,026,732
Building and Improvements				2,832,069
Gross Amount Carried at End of Period	6,858,801			6,858,801
Accumulated Depreciation	129,827			129,827
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,858,801
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	129,827
Operating Properties [Member] | 234 Moonachie Avenue [Member] [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				24,169,414
Land and Improvements				15,228,204
Building and Improvements				8,941,210
Gross Amount Carried at End of Period	24,169,414			24,169,414
Accumulated Depreciation	162,628			162,628
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	24,169,414
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	162,628
Operating Properties [Member] | 250 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,435,430
Initial Cost of Buildings				7,272,539
Costs Capitalized Subsequent to Acquisition				479,044
Land and Improvements				10,426,856
Building and Improvements				7,760,157
Gross Amount Carried at End of Period	18,187,013			18,187,013
Accumulated Depreciation	329,411			329,411
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	18,187,013
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	329,411
Operating Properties [Member] | 22750 Cactus Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				9,404,283
Initial Cost of Buildings				24,380,934
Costs Capitalized Subsequent to Acquisition				1,851,865
Land and Improvements				9,408,276
Building and Improvements				26,228,806
Gross Amount Carried at End of Period	35,637,082			35,637,082
Accumulated Depreciation	3,113,478			3,113,478
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	35,637,082
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,113,478
Operating Properties [Member] | 323 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,071,600
Initial Cost of Buildings				4,397,807
Costs Capitalized Subsequent to Acquisition				1,029,987
Land and Improvements				1,071,600
Building and Improvements				5,427,794
Gross Amount Carried at End of Period	6,499,394			6,499,394
Accumulated Depreciation	1,747,361			1,747,361
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,499,394
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,747,361
Operating Properties [Member] | 324 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,449,092
Initial Cost of Buildings				4,424,932
Costs Capitalized Subsequent to Acquisition				407,975
Land and Improvements				1,449,450
Building and Improvements				4,832,549
Gross Amount Carried at End of Period	6,281,999			6,281,999
Accumulated Depreciation	1,531,434			1,531,434
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,281,999
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,531,434
Operating Properties [Member] | 619 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,031,430
Initial Cost of Buildings				5,655,167
Costs Capitalized Subsequent to Acquisition				730,511
Land and Improvements				1,031,685
Building and Improvements				6,385,423
Gross Amount Carried at End of Period	7,417,108			7,417,108
Accumulated Depreciation	1,889,543			1,889,543
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,417,108
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,889,543
Operating Properties [Member] | 627 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,061,370
Initial Cost of Buildings				5,152,110
Costs Capitalized Subsequent to Acquisition				415,421
Land and Improvements				1,061,632
Building and Improvements				5,567,269
Gross Amount Carried at End of Period	6,628,901			6,628,901
Accumulated Depreciation	1,575,041			1,575,041
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,628,901
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,575,041
Operating Properties [Member] | 25 Coddington Crescent [Member] [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,766,328
Initial Cost of Buildings				8,341,701
Costs Capitalized Subsequent to Acquisition				11,835,679
Land and Improvements				1,766,328
Building and Improvements				10,069,351
Gross Amount Carried at End of Period	11,835,679			11,835,679
Accumulated Depreciation	76,843			76,843
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,835,679
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	76,843
Operating Properties [Member] | 4 Britain Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				699,424
Initial Cost of Buildings				5,896,241
Costs Capitalized Subsequent to Acquisition				7,482,435
Land and Improvements				699,424
Building and Improvements				6,783,011
Gross Amount Carried at End of Period	7,482,435			7,482,435
Accumulated Depreciation	53,082			53,082
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,482,435
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	53,082
Operating Properties [Member] | 1775 Hillcrest Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,318,956
Initial Cost of Buildings				4,379,239
Costs Capitalized Subsequent to Acquisition				860,030
Land and Improvements				1,321,595
Building and Improvements				5,236,630
Gross Amount Carried at End of Period	6,558,225			6,558,225
Accumulated Depreciation	143,389			143,389
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,558,225
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	143,389
Operating Properties [Member] | St Davids Way, Bermuda Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,545,374
Initial Cost of Buildings				21,279,020
Costs Capitalized Subsequent to Acquisition				26,462,690
Land and Improvements				3,545,374
Building and Improvements				22,917,316
Gross Amount Carried at End of Period	26,462,690			26,462,690
Accumulated Depreciation	163,468			163,468
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	26,462,690
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	163,468
Operating Properties [Member] | 1879 Lamont Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,976,000
Initial Cost of Buildings				8,099,579
Costs Capitalized Subsequent to Acquisition				2,090,522
Land and Improvements				2,011,030
Building and Improvements				10,155,071
Gross Amount Carried at End of Period	12,166,101			12,166,101
Accumulated Depreciation	3,762,008			3,762,008
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,166,101
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,762,008
Operating Properties [Member] | 350 Winmeyer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,778,400
Initial Cost of Buildings				7,289,165
Costs Capitalized Subsequent to Acquisition				1,729,188
Land and Improvements				1,809,927
Building and Improvements				8,986,826
Gross Amount Carried at End of Period	10,796,753			10,796,753
Accumulated Depreciation	3,029,788			3,029,788
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,796,753
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,029,788
Operating Properties [Member] | 1 Chadderton Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,397,990
Initial Cost of Buildings				15,045,200
Costs Capitalized Subsequent to Acquisition				19,742,036
Land and Improvements				3,397,990
Building and Improvements				16,344,046
Gross Amount Carried at End of Period	19,742,036			19,742,036
Accumulated Depreciation	118,106			118,106
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	19,742,036
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	118,106
Operating Properties [Member] | 4000 E Airport Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,686,533
Initial Cost of Buildings				10,125,772
Costs Capitalized Subsequent to Acquisition				723,876
Land and Improvements				2,686,533
Building and Improvements				10,849,648
Gross Amount Carried at End of Period	13,536,181			13,536,181
Accumulated Depreciation	1,826,827			1,826,827
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,536,181
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,826,827
Operating Properties [Member] | 1000 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				415,906
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,699,594
Land and Improvements				435,400
Building and Improvements				2,680,100
Gross Amount Carried at End of Period	3,115,500			3,115,500
Accumulated Depreciation	675,351			675,351
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,115,500
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	675,351
Operating Properties [Member] | 10003 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				680,312
Initial Cost of Buildings				2,120,754
Costs Capitalized Subsequent to Acquisition				1,379,008
Land and Improvements				680,312
Building and Improvements				3,499,762
Gross Amount Carried at End of Period	4,180,074			4,180,074
Accumulated Depreciation	1,587,470			1,587,470
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,180,074
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,587,470
Operating Properties [Member] | 10511 & 10611 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				517,554
Initial Cost of Buildings				2,568,186
Costs Capitalized Subsequent to Acquisition				719,885
Land and Improvements				522,991
Building and Improvements				3,282,634
Gross Amount Carried at End of Period	3,805,625			3,805,625
Accumulated Depreciation	1,793,683			1,793,683
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,805,625
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,793,683
Operating Properties [Member] | 10771 Palm Bay Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				664,605
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,515,652
Land and Improvements				685,383
Building and Improvements				2,494,874
Gross Amount Carried at End of Period	3,180,257			3,180,257
Accumulated Depreciation	1,036,885			1,036,885
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,180,257
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,036,885
Operating Properties [Member] | 1090 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				878,320
Initial Cost of Buildings				2,558,833
Costs Capitalized Subsequent to Acquisition				3,836,603
Land and Improvements				878,320
Building and Improvements				6,395,436
Gross Amount Carried at End of Period	7,273,756			7,273,756
Accumulated Depreciation	1,666,984			1,666,984
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,273,756
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,666,984
Operating Properties [Member] | 1600-1650 Central Florida Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				518,043
Initial Cost of Buildings				2,561,938
Costs Capitalized Subsequent to Acquisition				966,144
Land and Improvements				518,043
Building and Improvements				3,528,082
Gross Amount Carried at End of Period	4,046,125			4,046,125
Accumulated Depreciation	1,995,393			1,995,393
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,046,125
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,995,393
Operating Properties [Member] | 1902 Cypress Lake Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				523,512
Initial Cost of Buildings				3,191,790
Costs Capitalized Subsequent to Acquisition				1,576,299
Land and Improvements				538,512
Building and Improvements				4,753,089
Gross Amount Carried at End of Period	5,291,601			5,291,601
Accumulated Depreciation	2,523,921			2,523,921
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,291,601
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,523,921
Operating Properties [Member] | 2000 Park Oaks Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				913,201
Initial Cost of Buildings				6,818,610
Costs Capitalized Subsequent to Acquisition				993,299
Land and Improvements				913,201
Building and Improvements				7,811,909
Gross Amount Carried at End of Period	8,725,110			8,725,110
Accumulated Depreciation	1,380,151			1,380,151
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,725,110
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,380,151
Operating Properties [Member] | 2202 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,283,713
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,315,061
Land and Improvements				1,283,713
Building and Improvements				7,315,061
Gross Amount Carried at End of Period	8,598,774			8,598,774
Accumulated Depreciation	3,362,636			3,362,636
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,598,774
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,362,636
Operating Properties [Member] | 2212 Taft Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				838,853
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,084,540
Land and Improvements				767,953
Building and Improvements				4,155,440
Gross Amount Carried at End of Period	4,923,393			4,923,393
Accumulated Depreciation	1,521,775			1,521,775
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,923,393
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,521,775
Operating Properties [Member] | 2256 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				467,296
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,856,683
Land and Improvements				825,673
Building and Improvements				2,498,306
Gross Amount Carried at End of Period	3,323,979			3,323,979
Accumulated Depreciation	1,062,229			1,062,229
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,323,979
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,062,229
Operating Properties [Member] | 2351 Investors Row [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,261,924
Initial Cost of Buildings				7,496,249
Costs Capitalized Subsequent to Acquisition				1,930,820
Land and Improvements				2,271,785
Building and Improvements				9,417,208
Gross Amount Carried at End of Period	11,688,993			11,688,993
Accumulated Depreciation	3,385,169			3,385,169
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,688,993
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,385,169
Operating Properties [Member] | 2400 South Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				385,964
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,283,015
Land and Improvements				642,427
Building and Improvements				3,026,552
Gross Amount Carried at End of Period	3,668,979			3,668,979
Accumulated Depreciation	1,549,470			1,549,470
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,668,979
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,549,470
Operating Properties [Member] | 2412 Sand Lake Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,236,819
Initial Cost of Buildings				3,243,314
Costs Capitalized Subsequent to Acquisition				4,568,856
Land and Improvements				1,244,667
Building and Improvements				7,804,322
Gross Amount Carried at End of Period	9,048,989			9,048,989
Accumulated Depreciation	1,350,464			1,350,464
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,048,989
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,350,464
Operating Properties [Member] | 2416 Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				535,964
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,842,755
Land and Improvements				704,800
Building and Improvements				3,673,919
Gross Amount Carried at End of Period	4,378,719			4,378,719
Accumulated Depreciation	2,130,755			2,130,755
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,378,719
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,130,755
Operating Properties [Member] | 6918 Presidents Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				872,550
Initial Cost of Buildings				2,526,043
Costs Capitalized Subsequent to Acquisition				737,771
Land and Improvements				872,550
Building and Improvements				3,263,814
Gross Amount Carried at End of Period	4,136,364			4,136,364
Accumulated Depreciation	518,602			518,602
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,136,364
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	518,602
Operating Properties [Member] | 7022 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,443,510
Initial Cost of Buildings				6,775,194
Costs Capitalized Subsequent to Acquisition				742,426
Land and Improvements				1,457,286
Building and Improvements				7,503,845
Gross Amount Carried at End of Period	8,961,131			8,961,131
Accumulated Depreciation	2,413,321			2,413,321
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,961,131
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,413,321
Operating Properties [Member] | 7100 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,431,489
Initial Cost of Buildings				8,002,539
Costs Capitalized Subsequent to Acquisition				1,229,189
Land and Improvements				1,445,807
Building and Improvements				9,217,410
Gross Amount Carried at End of Period	10,663,217			10,663,217
Accumulated Depreciation	2,812,110			2,812,110
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,663,217
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,812,110
Operating Properties [Member] | 7101 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,553,537
Initial Cost of Buildings				5,702,243
Costs Capitalized Subsequent to Acquisition				683,338
Land and Improvements				1,570,863
Building and Improvements				6,368,255
Gross Amount Carried at End of Period	7,939,118			7,939,118
Accumulated Depreciation	2,003,125			2,003,125
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,939,118
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,003,125
Operating Properties [Member] | 7315 Kingspointe Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,931,697
Initial Cost of Buildings				6,388,203
Costs Capitalized Subsequent to Acquisition				3,004,875
Land and Improvements				1,932,004
Building and Improvements				9,392,771
Gross Amount Carried at End of Period	11,324,775			11,324,775
Accumulated Depreciation	4,210,338			4,210,338
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,324,775
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,210,338
Operating Properties [Member] | 851 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				332,992
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,800,616
Land and Improvements				373,500
Building and Improvements				2,760,108
Gross Amount Carried at End of Period	3,133,608			3,133,608
Accumulated Depreciation	789,066			789,066
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,133,608
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	789,066
Operating Properties [Member] | 950 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				443,989
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,817,146
Land and Improvements				464,800
Building and Improvements				2,796,335
Gross Amount Carried at End of Period	3,261,135			3,261,135
Accumulated Depreciation	736,047			736,047
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,261,135
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	736,047
Operating Properties [Member] | 9550 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				574,831
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,680,052
Land and Improvements				587,319
Building and Improvements				2,667,564
Gross Amount Carried at End of Period	3,254,883			3,254,883
Accumulated Depreciation	1,503,602			1,503,602
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,254,883
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,503,602
Operating Properties [Member] | 9700 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				252,850
Initial Cost of Buildings				1,297,923
Costs Capitalized Subsequent to Acquisition				185,097
Land and Improvements				252,850
Building and Improvements				1,483,020
Gross Amount Carried at End of Period	1,735,870			1,735,870
Accumulated Depreciation	800,355			800,355
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,735,870
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	800,355
Operating Properties [Member] | 9600 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				405,362
Initial Cost of Buildings				1,146,546
Costs Capitalized Subsequent to Acquisition				461,635
Land and Improvements				405,362
Building and Improvements				1,608,181
Gross Amount Carried at End of Period	2,013,543			2,013,543
Accumulated Depreciation	833,631			833,631
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,013,543
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	833,631
Operating Properties [Member] | 1050 Constitution Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,969,501
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				40,135,583
Land and Improvements				1,976,602
Building and Improvements				40,682,682
Gross Amount Carried at End of Period	42,659,284			42,659,284
Accumulated Depreciation	606,773			606,773
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	42,659,284
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	606,773
Operating Properties [Member] | 1 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				567,280
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				15,159,791
Land and Improvements				347,892
Building and Improvements				15,379,179
Gross Amount Carried at End of Period	15,727,071			15,727,071
Accumulated Depreciation	4,949,937			4,949,937
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,727,071
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,949,937
Operating Properties [Member] | 3 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				214,726
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				30,383,327
Land and Improvements				417,823
Building and Improvements				30,180,230
Gross Amount Carried at End of Period	30,598,053			30,598,053
Accumulated Depreciation	5,343,193			5,343,193
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	30,598,053
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,343,193
Operating Properties [Member] | 1200 Intrepid Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				404,883
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				31,029,101
Land and Improvements				455,507
Building and Improvements				30,978,477
Gross Amount Carried at End of Period	31,433,984			31,433,984
Accumulated Depreciation	1,485,896			1,485,896
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	31,433,984
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,485,896
Operating Properties [Member] | 150 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				567,531
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				14,232,898
Land and Improvements				569,349
Building and Improvements				14,231,080
Gross Amount Carried at End of Period	14,800,429			14,800,429
Accumulated Depreciation	2,686,999			2,686,999
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,800,429
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,686,999
Operating Properties [Member] | 201 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				243,905
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				22,543,251
Land and Improvements				449,013
Building and Improvements				22,338,143
Gross Amount Carried at End of Period	22,787,156			22,787,156
Accumulated Depreciation	2,736,766			2,736,766
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,787,156
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,736,766
Operating Properties [Member] | 351 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				359,864
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				16,768,954
Land and Improvements				367,016
Building and Improvements				16,761,802
Gross Amount Carried at End of Period	17,128,818			17,128,818
Accumulated Depreciation	951,162			951,162
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	17,128,818
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	951,162
Operating Properties [Member] | 4000 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,255,507
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				10,816,114
Land and Improvements				1,142,358
Building and Improvements				10,929,263
Gross Amount Carried at End of Period	12,071,621			12,071,621
Accumulated Depreciation	823,673			823,673
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,071,621
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	823,673
Operating Properties [Member] | 4020 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				51,784
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,165,151
Land and Improvements				616,467
Building and Improvements				6,600,468
Gross Amount Carried at End of Period	7,216,935			7,216,935
Accumulated Depreciation	1,248,308			1,248,308
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,216,935
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,248,308
Operating Properties [Member] | 4050 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				46,301
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,034,962
Land and Improvements				616,670
Building and Improvements				6,464,593
Gross Amount Carried at End of Period	7,081,263			7,081,263
Accumulated Depreciation	1,424,780			1,424,780
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,081,263
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,424,780
Operating Properties [Member] | 4300 South 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				402,673
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				34,930,238
Land and Improvements				413,030
Building and Improvements				34,919,881
Gross Amount Carried at End of Period	35,332,911			35,332,911
Accumulated Depreciation	8,438,036			8,438,036
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	35,332,911
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	8,438,036
Operating Properties [Member] | 4701 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				419,107
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				13,300,078
Land and Improvements				435,763
Building and Improvements				13,283,422
Gross Amount Carried at End of Period	13,719,185			13,719,185
Accumulated Depreciation	1,063,742			1,063,742
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,719,185
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,063,742
Operating Properties [Member] | 4751 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				992,965
Initial Cost of Buildings				331,924
Costs Capitalized Subsequent to Acquisition				7,829,618
Land and Improvements				613,248
Building and Improvements				8,541,259
Gross Amount Carried at End of Period	9,154,507			9,154,507
Accumulated Depreciation	3,595,406			3,595,406
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,154,507
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,595,406
Operating Properties [Member] | 4775 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				891,892
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,578,803
Land and Improvements				366,982
Building and Improvements				6,103,713
Gross Amount Carried at End of Period	6,470,695			6,470,695
Accumulated Depreciation	1,803,316			1,803,316
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,470,695
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,803,316
Operating Properties [Member] | 8th & Walnut Streets [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				36,752,064
Initial Cost of Land				734,275
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				45,396,637
Land and Improvements				0
Building and Improvements				46,130,912
Gross Amount Carried at End of Period	46,130,912			46,130,912
Accumulated Depreciation	5,562,538			5,562,538
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	46,130,912
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	5,562,538
Operating Properties [Member] | 2626 South 7th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,519,510
Initial Cost of Buildings				3,798,560
Costs Capitalized Subsequent to Acquisition				3,442,614
Land and Improvements				2,519,510
Building and Improvements				7,241,174
Gross Amount Carried at End of Period	9,760,684			9,760,684
Accumulated Depreciation	1,712,070			1,712,070
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,760,684
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,712,070
Operating Properties [Member] | 563 South 63rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,523,427
Initial Cost of Buildings				14,581,705
Costs Capitalized Subsequent to Acquisition				12,211,689
Land and Improvements				5,636,070
Building and Improvements				26,680,751
Gross Amount Carried at End of Period	32,316,821			32,316,821
Accumulated Depreciation	3,819,911			3,819,911
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	32,316,821
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,819,911
Operating Properties [Member] | 1500 S 71st Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,234,407
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				21,315,017
Land and Improvements				5,547,810
Building and Improvements				20,001,614
Gross Amount Carried at End of Period	25,549,424			25,549,424
Accumulated Depreciation	652,047			652,047
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	25,549,424
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	652,047
Operating Properties [Member] | 7205 W Buckeye Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,514,425
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,845,318
Land and Improvements				2,514,425
Building and Improvements				11,845,318
Gross Amount Carried at End of Period	14,359,743			14,359,743
Accumulated Depreciation	594,030			594,030
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,359,743
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	594,030
Operating Properties [Member] | 1000 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				706,660
Initial Cost of Buildings				5,894,330
Costs Capitalized Subsequent to Acquisition				1,095,222
Land and Improvements				706,660
Building and Improvements				6,989,553
Gross Amount Carried at End of Period	7,696,213			7,696,213
Accumulated Depreciation	1,076,247			1,076,247
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,696,213
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,076,247
Operating Properties [Member] | 1901 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				555,168
Initial Cost of Buildings				6,401,789
Costs Capitalized Subsequent to Acquisition				720,056
Land and Improvements				555,168
Building and Improvements				7,121,845
Gross Amount Carried at End of Period	7,677,013			7,677,013
Accumulated Depreciation	1,274,999			1,274,999
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,677,013
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,274,999
Operating Properties [Member] | 1909 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				551,706
Initial Cost of Buildings				5,797,440
Costs Capitalized Subsequent to Acquisition				339,750
Land and Improvements				551,706
Building and Improvements				6,137,190
Gross Amount Carried at End of Period	6,688,896			6,688,896
Accumulated Depreciation	1,076,450			1,076,450
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,688,896
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,076,450
Operating Properties [Member] | 3605 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,047,996
Initial Cost of Buildings				9,218,748
Costs Capitalized Subsequent to Acquisition				1,970,078
Land and Improvements				1,047,996
Building and Improvements				11,188,825
Gross Amount Carried at End of Period	12,236,821			12,236,821
Accumulated Depreciation	2,318,952			2,318,952
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,236,821
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,318,952
Operating Properties [Member] | 3701 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				877,564
Initial Cost of Buildings				7,460,686
Costs Capitalized Subsequent to Acquisition				772,833
Land and Improvements				877,564
Building and Improvements				8,233,518
Gross Amount Carried at End of Period	9,111,082			9,111,082
Accumulated Depreciation	1,441,738			1,441,738
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,111,082
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,441,738
Operating Properties [Member] | 800 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				580,456
Initial Cost of Buildings				5,681,283
Costs Capitalized Subsequent to Acquisition				1,600,103
Land and Improvements				580,456
Building and Improvements				7,281,386
Gross Amount Carried at End of Period	7,861,842			7,861,842
Accumulated Depreciation	1,349,144			1,349,144
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,861,842
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,349,144
Operating Properties [Member] | 900 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				723,534
Initial Cost of Buildings				6,004,923
Costs Capitalized Subsequent to Acquisition				778,787
Land and Improvements				723,534
Building and Improvements				6,783,710
Gross Amount Carried at End of Period	7,507,244			7,507,244
Accumulated Depreciation	1,246,138			1,246,138
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,507,244
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,246,138
Operating Properties [Member] | 9801 80th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,692,077
Initial Cost of Buildings				7,934,794
Costs Capitalized Subsequent to Acquisition				58,274
Land and Improvements				1,689,726
Building and Improvements				7,995,419
Gross Amount Carried at End of Period	9,685,145			9,685,145
Accumulated Depreciation	4,010,311			4,010,311
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,685,145
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,010,311
Operating Properties [Member] | 14630-14650 28th Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				198,205
Initial Cost of Buildings				1,793,422
Costs Capitalized Subsequent to Acquisition				1,096,872
Land and Improvements				198,205
Building and Improvements				2,890,293
Gross Amount Carried at End of Period	3,088,498			3,088,498
Accumulated Depreciation	1,614,891			1,614,891
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,088,498
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,614,891
Operating Properties [Member] | 2920 Northwest Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				392,026
Initial Cost of Buildings				3,433,678
Costs Capitalized Subsequent to Acquisition				850,998
Land and Improvements				384,235
Building and Improvements				4,292,467
Gross Amount Carried at End of Period	4,676,702			4,676,702
Accumulated Depreciation	2,195,023			2,195,023
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,676,702
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,195,023
Operating Properties [Member] | 5905 Trenton Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,616,360
Initial Cost of Buildings				4,487,462
Costs Capitalized Subsequent to Acquisition				735,223
Land and Improvements				1,616,360
Building and Improvements				5,222,684
Gross Amount Carried at End of Period	6,839,044			6,839,044
Accumulated Depreciation	1,060,984			1,060,984
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,839,044
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,060,984
Operating Properties [Member] | 6055 Nathan Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,327,017
Initial Cost of Buildings				4,527,404
Costs Capitalized Subsequent to Acquisition				1,180,962
Land and Improvements				1,327,017
Building and Improvements				5,708,366
Gross Amount Carried at End of Period	7,035,383			7,035,383
Accumulated Depreciation	1,061,431			1,061,431
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,035,383
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,061,431
Operating Properties [Member] | 1400 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,157,049
Initial Cost of Buildings				4,620,956
Costs Capitalized Subsequent to Acquisition				1,447,640
Land and Improvements				1,157,049
Building and Improvements				6,068,596
Gross Amount Carried at End of Period	7,225,645			7,225,645
Accumulated Depreciation	3,133,452			3,133,452
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,225,645
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,133,452
Operating Properties [Member] | 1405 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				392,138
Initial Cost of Buildings				1,565,787
Costs Capitalized Subsequent to Acquisition				443,460
Land and Improvements				392,138
Building and Improvements				2,009,248
Gross Amount Carried at End of Period	2,401,386			2,401,386
Accumulated Depreciation	1,111,539			1,111,539
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,401,386
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,111,539
Operating Properties [Member] | 1500 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				972,232
Initial Cost of Buildings				3,892,085
Costs Capitalized Subsequent to Acquisition				2,133,854
Land and Improvements				972,232
Building and Improvements				6,025,939
Gross Amount Carried at End of Period	6,998,171			6,998,171
Accumulated Depreciation	2,552,632			2,552,632
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,998,171
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,552,632
Operating Properties [Member] | 1501 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				203,247
Initial Cost of Buildings				811,093
Costs Capitalized Subsequent to Acquisition				370,236
Land and Improvements				203,247
Building and Improvements				1,181,330
Gross Amount Carried at End of Period	1,384,577			1,384,577
Accumulated Depreciation	664,965			664,965
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,384,577
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	664,965
Operating Properties [Member] | 1601 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				203,247
Initial Cost of Buildings				811,093
Costs Capitalized Subsequent to Acquisition				208,224
Land and Improvements				203,247
Building and Improvements				1,019,318
Gross Amount Carried at End of Period	1,222,565			1,222,565
Accumulated Depreciation	510,197			510,197
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,222,565
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	510,197
Operating Properties [Member] | 1651 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				203,247
Initial Cost of Buildings				811,093
Costs Capitalized Subsequent to Acquisition				154,435
Land and Improvements				203,247
Building and Improvements				965,529
Gross Amount Carried at End of Period	1,168,776			1,168,776
Accumulated Depreciation	484,879			484,879
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,168,776
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	484,879
Operating Properties [Member] | 2201-2215 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,120,328
Initial Cost of Buildings				3,427,358
Costs Capitalized Subsequent to Acquisition				131,571
Land and Improvements				1,120,328
Building and Improvements				3,558,929
Gross Amount Carried at End of Period	4,679,257			4,679,257
Accumulated Depreciation	604,820			604,820
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,679,257
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	604,820
Operating Properties [Member] | 2250-2270 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				993,015
Initial Cost of Buildings				2,423,174
Costs Capitalized Subsequent to Acquisition				164,947
Land and Improvements				993,015
Building and Improvements				2,588,121
Gross Amount Carried at End of Period	3,581,136			3,581,136
Accumulated Depreciation	452,707			452,707
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,581,136
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	452,707
Operating Properties [Member] | 2280-2300 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				906,947
Initial Cost of Buildings				2,157,802
Costs Capitalized Subsequent to Acquisition				205,748
Land and Improvements				906,947
Building and Improvements				2,363,551
Gross Amount Carried at End of Period	3,270,498			3,270,498
Accumulated Depreciation	440,559			440,559
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,270,498
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	440,559
Operating Properties [Member] | 2301-2329 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,268,707
Initial Cost of Buildings				3,079,811
Costs Capitalized Subsequent to Acquisition				194,453
Land and Improvements				1,268,707
Building and Improvements				3,274,264
Gross Amount Carried at End of Period	4,542,971			4,542,971
Accumulated Depreciation	541,027			541,027
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,542,971
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	541,027
Operating Properties [Member] | 3000 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,087,554
Initial Cost of Buildings				2,897,117
Costs Capitalized Subsequent to Acquisition				151,201
Land and Improvements				1,087,554
Building and Improvements				3,048,318
Gross Amount Carried at End of Period	4,135,872			4,135,872
Accumulated Depreciation	519,491			519,491
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,135,872
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	519,491
Operating Properties [Member] | 3001-3037 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,548,542
Initial Cost of Buildings				3,512,041
Costs Capitalized Subsequent to Acquisition				327,643
Land and Improvements				1,548,542
Building and Improvements				3,839,685
Gross Amount Carried at End of Period	5,388,227			5,388,227
Accumulated Depreciation	759,253			759,253
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,388,227
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	759,253
Operating Properties [Member] | 3012-3050 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,112,781
Initial Cost of Buildings				2,763,862
Costs Capitalized Subsequent to Acquisition				259,688
Land and Improvements				1,112,781
Building and Improvements				3,023,549
Gross Amount Carried at End of Period	4,136,330			4,136,330
Accumulated Depreciation	542,917			542,917
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,136,330
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	542,917
Operating Properties [Member] | 595 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				359,933
Initial Cost of Buildings				1,437,116
Costs Capitalized Subsequent to Acquisition				722,833
Land and Improvements				359,933
Building and Improvements				2,159,949
Gross Amount Carried at End of Period	2,519,882			2,519,882
Accumulated Depreciation	1,342,770			1,342,770
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,519,882
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,342,770
Operating Properties [Member] | 601 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				164,413
Initial Cost of Buildings				655,933
Costs Capitalized Subsequent to Acquisition				279,326
Land and Improvements				164,413
Building and Improvements				935,259
Gross Amount Carried at End of Period	1,099,672			1,099,672
Accumulated Depreciation	558,243			558,243
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,099,672
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	558,243
Operating Properties [Member] | 605 SW 16th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				310,778
Initial Cost of Buildings				1,238,324
Costs Capitalized Subsequent to Acquisition				294,844
Land and Improvements				310,178
Building and Improvements				1,533,768
Gross Amount Carried at End of Period	1,843,946			1,843,946
Accumulated Depreciation	720,079			720,079
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,843,946
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	720,079
Operating Properties [Member] | 2459 Almond Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Initial Cost of Land				3,810,171
Initial Cost of Buildings				11,979,923
Costs Capitalized Subsequent to Acquisition				211,352
Land and Improvements				3,810,839
Building and Improvements				12,190,607
Gross Amount Carried at End of Period	16,001,446			16,001,446
Accumulated Depreciation	441,125			441,125
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,001,446
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	441,125
Operating Properties [Member] | 1221 N Alder Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Initial Cost of Land				17,280,833
Initial Cost of Buildings				72,740,859
Costs Capitalized Subsequent to Acquisition				84,913
Land and Improvements				17,289,021
Building and Improvements				72,817,584
Gross Amount Carried at End of Period	90,106,605			90,106,605
Accumulated Depreciation	1,833,441			1,833,441
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	90,106,605
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,833,441
Operating Properties [Member] | 1543 N Alder Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				53,779,093
Land and Improvements				25,480,304
Building and Improvements				28,298,789
Gross Amount Carried at End of Period	53,779,093			53,779,093
Accumulated Depreciation	377,929			377,929
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	53,779,093
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	377,929
Operating Properties [Member] | 1920 West Baseline Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				9,361,943
Initial Cost of Buildings				17,970,709
Costs Capitalized Subsequent to Acquisition				464,691
Land and Improvements				9,411,621
Building and Improvements				18,385,722
Gross Amount Carried at End of Period	27,797,343			27,797,343
Accumulated Depreciation	1,890,258			1,890,258
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	27,797,343
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,890,258
Operating Properties [Member] | 4101-4127 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				310,854
Initial Cost of Buildings				2,279,597
Costs Capitalized Subsequent to Acquisition				2,089,912
Land and Improvements				310,854
Building and Improvements				4,369,509
Gross Amount Carried at End of Period	4,680,363			4,680,363
Accumulated Depreciation	2,194,452			2,194,452
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,680,363
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,194,452
Operating Properties [Member] | 4201-4261 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				693,203
Initial Cost of Buildings				5,083,493
Costs Capitalized Subsequent to Acquisition				2,566,101
Land and Improvements				693,203
Building and Improvements				7,649,594
Gross Amount Carried at End of Period	8,342,797			8,342,797
Accumulated Depreciation	4,372,081			4,372,081
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,342,797
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,372,081
Operating Properties [Member] | 4263-4299 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				256,203
Initial Cost of Buildings				2,549,649
Costs Capitalized Subsequent to Acquisition				3,066,006
Land and Improvements				256,203
Building and Improvements				5,615,655
Gross Amount Carried at End of Period	5,871,858			5,871,858
Accumulated Depreciation	3,015,128			3,015,128
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,871,858
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,015,128
Operating Properties [Member] | 4263F-N. Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				91,476
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,004,066
Land and Improvements				91,599
Building and Improvements				2,003,943
Gross Amount Carried at End of Period	2,095,542			2,095,542
Accumulated Depreciation	1,130,225			1,130,225
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,095,542
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,130,225
Operating Properties [Member] | 4301-4335 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				223,696
Initial Cost of Buildings				1,640,435
Costs Capitalized Subsequent to Acquisition				2,945,220
Land and Improvements				223,696
Building and Improvements				4,585,655
Gross Amount Carried at End of Period	4,809,351			4,809,351
Accumulated Depreciation	2,353,099			2,353,099
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,809,351
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,353,099
Operating Properties [Member] | 4337-4379 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				325,303
Initial Cost of Buildings				2,385,557
Costs Capitalized Subsequent to Acquisition				2,152,033
Land and Improvements				325,303
Building and Improvements				4,537,590
Gross Amount Carried at End of Period	4,862,893			4,862,893
Accumulated Depreciation	2,059,169			2,059,169
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,862,893
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,059,169
Operating Properties [Member] | 4401-4445 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				615,038
Initial Cost of Buildings				4,510,272
Costs Capitalized Subsequent to Acquisition				681,107
Land and Improvements				615,038
Building and Improvements				5,191,379
Gross Amount Carried at End of Period	5,806,417			5,806,417
Accumulated Depreciation	3,013,701			3,013,701
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,806,417
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,013,701
Operating Properties [Member] | 4447-4491 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				454,056
Initial Cost of Buildings				2,729,742
Costs Capitalized Subsequent to Acquisition				518,293
Land and Improvements				454,056
Building and Improvements				3,248,035
Gross Amount Carried at End of Period	3,702,091			3,702,091
Accumulated Depreciation	1,792,248			1,792,248
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,702,091
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,792,248
Operating Properties [Member] | 4501-4549 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				486,166
Initial Cost of Buildings				3,565,211
Costs Capitalized Subsequent to Acquisition				588,033
Land and Improvements				486,166
Building and Improvements				4,153,244
Gross Amount Carried at End of Period	4,639,410			4,639,410
Accumulated Depreciation	2,551,191			2,551,191
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,639,410
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,551,191
Operating Properties [Member] | 4551-4593 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				474,360
Initial Cost of Buildings				3,478,646
Costs Capitalized Subsequent to Acquisition				1,025,589
Land and Improvements				474,360
Building and Improvements				4,504,235
Gross Amount Carried at End of Period	4,978,595			4,978,595
Accumulated Depreciation	2,943,011			2,943,011
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,978,595
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,943,011
Operating Properties [Member] | 4601-4643 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				652,455
Initial Cost of Buildings				4,784,675
Costs Capitalized Subsequent to Acquisition				1,194,389
Land and Improvements				652,455
Building and Improvements				5,979,064
Gross Amount Carried at End of Period	6,631,519			6,631,519
Accumulated Depreciation	3,558,663			3,558,663
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,631,519
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,558,663
Operating Properties [Member] | 4645-4683 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				404,616
Initial Cost of Buildings				2,967,187
Costs Capitalized Subsequent to Acquisition				643,220
Land and Improvements				404,616
Building and Improvements				3,610,407
Gross Amount Carried at End of Period	4,015,023			4,015,023
Accumulated Depreciation	2,193,223			2,193,223
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,015,023
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,193,223
Operating Properties [Member] | 4717-4729 Eubank Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				449,447
Initial Cost of Buildings				3,294,697
Costs Capitalized Subsequent to Acquisition				2,250,479
Land and Improvements				452,263
Building and Improvements				5,542,360
Gross Amount Carried at End of Period	5,994,623			5,994,623
Accumulated Depreciation	3,268,835			3,268,835
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,994,623
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,268,835
Operating Properties [Member] | 510 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				261,961
Initial Cost of Buildings				2,110,874
Costs Capitalized Subsequent to Acquisition				641,720
Land and Improvements				262,210
Building and Improvements				2,752,345
Gross Amount Carried at End of Period	3,014,555			3,014,555
Accumulated Depreciation	1,402,295			1,402,295
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,014,555
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,402,295
Operating Properties [Member] | 520 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				486,118
Initial Cost of Buildings				4,083,582
Costs Capitalized Subsequent to Acquisition				746,952
Land and Improvements				486,598
Building and Improvements				4,830,054
Gross Amount Carried at End of Period	5,316,652			5,316,652
Accumulated Depreciation	2,623,833			2,623,833
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,316,652
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,623,833
Operating Properties [Member] | 530 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				266,883
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,682,192
Land and Improvements				334,772
Building and Improvements				2,614,303
Gross Amount Carried at End of Period	2,949,075			2,949,075
Accumulated Depreciation	1,367,736			1,367,736
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,949,075
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,367,736
Operating Properties [Member] | 540 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				742,300
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,433,394
Land and Improvements				1,066,839
Building and Improvements				5,108,855
Gross Amount Carried at End of Period	6,175,694			6,175,694
Accumulated Depreciation	1,405,045			1,405,045
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,175,694
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,405,045
Operating Properties [Member] | 5600-5626 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				489,941
Initial Cost of Buildings				3,592,900
Costs Capitalized Subsequent to Acquisition				669,679
Land and Improvements				489,941
Building and Improvements				4,262,579
Gross Amount Carried at End of Period	4,752,520			4,752,520
Accumulated Depreciation	2,468,118			2,468,118
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,752,520
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,468,118
Operating Properties [Member] | 5601-5659 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				705,660
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,755,118
Land and Improvements				720,100
Building and Improvements				4,740,678
Gross Amount Carried at End of Period	5,460,778			5,460,778
Accumulated Depreciation	2,795,547			2,795,547
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,460,778
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,795,547
Operating Properties [Member] | 5650-5674 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				644,384
Initial Cost of Buildings				4,025,480
Costs Capitalized Subsequent to Acquisition				933,150
Land and Improvements				644,384
Building and Improvements				4,958,630
Gross Amount Carried at End of Period	5,603,014			5,603,014
Accumulated Depreciation	2,738,437			2,738,437
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,603,014
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,738,437
Operating Properties [Member] | 5700 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				408,729
Initial Cost of Buildings				2,697,348
Costs Capitalized Subsequent to Acquisition				1,248,569
Land and Improvements				408,729
Building and Improvements				3,945,917
Gross Amount Carried at End of Period	4,354,646			4,354,646
Accumulated Depreciation	2,507,746			2,507,746
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,354,646
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,507,746
Operating Properties [Member] | 5701-5799 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				694,644
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,798,481
Land and Improvements				700,503
Building and Improvements				5,792,622
Gross Amount Carried at End of Period	6,493,125			6,493,125
Accumulated Depreciation	2,925,775			2,925,775
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,493,125
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,925,775
Operating Properties [Member] | 5800 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				604,146
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,590,970
Land and Improvements				604,146
Building and Improvements				7,590,970
Gross Amount Carried at End of Period	8,195,116			8,195,116
Accumulated Depreciation	643,207			643,207
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,195,116
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	643,207
Operating Properties [Member] | 5900 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				676,661
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,981,687
Land and Improvements				687,898
Building and Improvements				4,970,450
Gross Amount Carried at End of Period	5,658,348			5,658,348
Accumulated Depreciation	2,803,370			2,803,370
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,658,348
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,803,370
Operating Properties [Member] | 6000 Eastport Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				872,901
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,490,092
Land and Improvements				901,666
Building and Improvements				7,461,327
Gross Amount Carried at End of Period	8,362,993			8,362,993
Accumulated Depreciation	2,031,498			2,031,498
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,362,993
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,031,498
Operating Properties [Member] | 6530 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				305,821
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,440,754
Land and Improvements				335,061
Building and Improvements				5,411,514
Gross Amount Carried at End of Period	5,746,575			5,746,575
Accumulated Depreciation	2,627,699			2,627,699
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,746,575
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,627,699
Operating Properties [Member] | 6532 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				354,903
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,029,128
Land and Improvements				399,988
Building and Improvements				3,984,043
Gross Amount Carried at End of Period	4,384,031			4,384,031
Accumulated Depreciation	2,260,621			2,260,621
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,384,031
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,260,621
Operating Properties [Member] | 13098 George Weber Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				895,811
Initial Cost of Buildings				6,004,189
Costs Capitalized Subsequent to Acquisition				1,311,797
Land and Improvements				895,811
Building and Improvements				7,315,986
Gross Amount Carried at End of Period	8,211,797			8,211,797
Accumulated Depreciation	1,351,177			1,351,177
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,211,797
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,351,177
Operating Properties [Member] | 13220 Wilfred Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				508,532
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,756,860
Land and Improvements				1,396,324
Building and Improvements				10,869,068
Gross Amount Carried at End of Period	12,265,392			12,265,392
Accumulated Depreciation	1,512,312			1,512,312
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,265,392
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,512,312
Operating Properties [Member] | 13225 Brockton Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,048,093
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				10,464,170
Land and Improvements				1,066,159
Building and Improvements				10,446,104
Gross Amount Carried at End of Period	11,512,263			11,512,263
Accumulated Depreciation	1,404,988			1,404,988
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,512,263
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,404,988
Operating Properties [Member] | 1070 Windham Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,672,143
Initial Cost of Buildings				24,144,864
Costs Capitalized Subsequent to Acquisition				1,238,550
Land and Improvements				8,672,143
Building and Improvements				25,383,414
Gross Amount Carried at End of Period	34,055,557			34,055,557
Accumulated Depreciation	4,189,884			4,189,884
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	34,055,557
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,189,884
Operating Properties [Member] | 1550 Central Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,884,492
Initial Cost of Buildings				10,439,793
Costs Capitalized Subsequent to Acquisition				1,444,499
Land and Improvements				2,884,492
Building and Improvements				11,884,292
Gross Amount Carried at End of Period	14,768,784			14,768,784
Accumulated Depreciation	2,164,340			2,164,340
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,768,784
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,164,340
Operating Properties [Member] | 9724 Alabama Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,140,486
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(56,250)
Land and Improvements				4,084,236
Building and Improvements				10,914,982
Gross Amount Carried at End of Period	14,999,218			14,999,218
Accumulated Depreciation	23,175			23,175
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,999,218
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	23,175
Operating Properties [Member] | 1135 Aviation Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,035,034
Initial Cost of Buildings				2,844,962
Costs Capitalized Subsequent to Acquisition				488,199
Land and Improvements				3,035,034
Building and Improvements				3,333,161
Gross Amount Carried at End of Period	6,368,195			6,368,195
Accumulated Depreciation	642,395			642,395
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,368,195
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	642,395
Operating Properties [Member] | 5800 Technology Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,741,867
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,041,734
Land and Improvements				1,744,160
Building and Improvements				12,039,441
Gross Amount Carried at End of Period	13,783,601			13,783,601
Accumulated Depreciation	726,814			726,814
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,783,601
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	726,814
Operating Properties [Member] | 8715 Bollman Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,263,237
Initial Cost of Buildings				2,633,210
Costs Capitalized Subsequent to Acquisition				218,782
Land and Improvements				1,263,237
Building and Improvements				2,851,992
Gross Amount Carried at End of Period	4,115,229			4,115,229
Accumulated Depreciation	531,258			531,258
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,115,229
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	531,258
Operating Properties [Member] | 1150 Gateway Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,126,865
Initial Cost of Buildings				5,684,178
Costs Capitalized Subsequent to Acquisition				207,627
Land and Improvements				1,126,865
Building and Improvements				5,891,805
Gross Amount Carried at End of Period	7,018,670			7,018,670
Accumulated Depreciation	981,977			981,977
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,018,670
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	981,977
Operating Properties [Member] | 5555 12th Avenue East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				887,285
Initial Cost of Buildings				5,321,200
Costs Capitalized Subsequent to Acquisition				805,245
Land and Improvements				887,285
Building and Improvements				6,126,445
Gross Amount Carried at End of Period	7,013,730			7,013,730
Accumulated Depreciation	1,049,514			1,049,514
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,013,730
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,049,514
Operating Properties [Member] | 5651 Innovation Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,551,579
Initial Cost of Buildings				9,541,234
Costs Capitalized Subsequent to Acquisition				1,989,410
Land and Improvements				1,552,083
Building and Improvements				11,530,140
Gross Amount Carried at End of Period	13,082,223			13,082,223
Accumulated Depreciation	939,155			939,155
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,082,223
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	939,155
Operating Properties [Member] | 12110 Champion Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,337,271
Initial Cost of Buildings				6,135,118
Costs Capitalized Subsequent to Acquisition				730,402
Land and Improvements				1,337,271
Building and Improvements				6,865,521
Gross Amount Carried at End of Period	8,202,792			8,202,792
Accumulated Depreciation	1,334,626			1,334,626
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,202,792
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,334,626
Operating Properties [Member] | 9300 Old Scotland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,232,633
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				84,609,660
Land and Improvements				12,933,027
Building and Improvements				81,909,266
Gross Amount Carried at End of Period	94,842,293			94,842,293
Accumulated Depreciation	10,842,342			10,842,342
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	94,842,293
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	10,842,342
Operating Properties [Member] | 3990 Heritage Oak Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,964,140
Initial Cost of Buildings				10,667,267
Costs Capitalized Subsequent to Acquisition				356,197
Land and Improvements				1,964,140
Building and Improvements				11,023,464
Gross Amount Carried at End of Period	12,987,604			12,987,604
Accumulated Depreciation	1,762,737			1,762,737
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,987,604
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,762,737
Operating Properties [Member] | 3654-3668 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				643,639
Initial Cost of Buildings				1,645,058
Costs Capitalized Subsequent to Acquisition				250,143
Land and Improvements				643,639
Building and Improvements				1,895,201
Gross Amount Carried at End of Period	2,538,840			2,538,840
Accumulated Depreciation	361,656			361,656
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,538,840
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	361,656
Operating Properties [Member] | 3701 Illinois Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				672,500
Initial Cost of Buildings				1,288,924
Costs Capitalized Subsequent to Acquisition				135,971
Land and Improvements				672,500
Building and Improvements				1,424,895
Gross Amount Carried at End of Period	2,097,395			2,097,395
Accumulated Depreciation	300,560			300,560
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,097,395
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	300,560
Operating Properties [Member] | 3950-3980 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				851,080
Initial Cost of Buildings				3,027,753
Costs Capitalized Subsequent to Acquisition				531,111
Land and Improvements				851,080
Building and Improvements				3,558,864
Gross Amount Carried at End of Period	4,409,944			4,409,944
Accumulated Depreciation	620,639			620,639
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,409,944
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	620,639
Operating Properties [Member] | 1501 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				283,474
Initial Cost of Buildings				2,230,868
Costs Capitalized Subsequent to Acquisition				176,960
Land and Improvements				283,474
Building and Improvements				2,407,827
Gross Amount Carried at End of Period	2,691,301			2,691,301
Accumulated Depreciation	418,656			418,656
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,691,301
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	418,656
Operating Properties [Member] | 1527 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				374,284
Initial Cost of Buildings				2,987,226
Costs Capitalized Subsequent to Acquisition				329,505
Land and Improvements				374,284
Building and Improvements				3,316,731
Gross Amount Carried at End of Period	3,691,015			3,691,015
Accumulated Depreciation	561,602			561,602
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,691,015
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	561,602
Operating Properties [Member] | 1551 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				699,797
Initial Cost of Buildings				5,214,438
Costs Capitalized Subsequent to Acquisition				1,049,296
Land and Improvements				699,797
Building and Improvements				6,263,734
Gross Amount Carried at End of Period	6,963,531			6,963,531
Accumulated Depreciation	1,210,288			1,210,288
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,963,531
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,210,288
Operating Properties [Member] | 1 Mirrlees Drive, Hazel Grove [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,866,851
Initial Cost of Buildings				13,756,142
Costs Capitalized Subsequent to Acquisition				16,783,468
Land and Improvements				1,866,851
Building and Improvements				14,916,617
Gross Amount Carried at End of Period	16,783,468			16,783,468
Accumulated Depreciation	107,500			107,500
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,783,468
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	107,500
Operating Properties [Member] | 6900 Harbor View Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				904,052
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,985,558
Land and Improvements				807,006
Building and Improvements				9,082,604
Gross Amount Carried at End of Period	9,889,610			9,889,610
Accumulated Depreciation	3,071,800			3,071,800
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,889,610
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,071,800
Operating Properties [Member] | 6920 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				603,391
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,811,311
Land and Improvements				2,628,635
Building and Improvements				4,786,067
Gross Amount Carried at End of Period	7,414,702			7,414,702
Accumulated Depreciation	964,958			964,958
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,414,702
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	964,958
Operating Properties [Member] | 6950 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				929,844
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,443,948
Land and Improvements				794,848
Building and Improvements				6,578,944
Gross Amount Carried at End of Period	7,373,792			7,373,792
Accumulated Depreciation	2,268,848			2,268,848
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,373,792
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,268,848
Operating Properties [Member] | 1516 Fryar Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,675,402
Initial Cost of Buildings				5,079,543
Costs Capitalized Subsequent to Acquisition				1,196,146
Land and Improvements				1,675,402
Building and Improvements				6,275,689
Gross Amount Carried at End of Period	7,951,091			7,951,091
Accumulated Depreciation	1,226,516			1,226,516
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,951,091
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,226,516
Operating Properties [Member] | 3401-3409 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				556,952
Initial Cost of Buildings				3,849,236
Costs Capitalized Subsequent to Acquisition				22,919
Land and Improvements				556,952
Building and Improvements				3,872,155
Gross Amount Carried at End of Period	4,429,107			4,429,107
Accumulated Depreciation	592,900			592,900
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,429,107
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	592,900
Operating Properties [Member] | 3502 Riga Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				201,600
Initial Cost of Buildings				1,263,131
Costs Capitalized Subsequent to Acquisition				274,110
Land and Improvements				201,600
Building and Improvements				1,537,241
Gross Amount Carried at End of Period	1,738,841			1,738,841
Accumulated Depreciation	236,984			236,984
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,738,841
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	236,984
Operating Properties [Member] | 3505 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				936,336
Initial Cost of Buildings				7,155,520
Costs Capitalized Subsequent to Acquisition				(145,469)
Land and Improvements				936,336
Building and Improvements				7,010,051
Gross Amount Carried at End of Period	7,946,387			7,946,387
Accumulated Depreciation	1,061,076			1,061,076
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,946,387
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,061,076
Operating Properties [Member] | 3608 Queen Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				650,384
Initial Cost of Buildings				4,764,301
Costs Capitalized Subsequent to Acquisition				251,943
Land and Improvements				650,384
Building and Improvements				5,016,244
Gross Amount Carried at End of Period	5,666,628			5,666,628
Accumulated Depreciation	827,248			827,248
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,666,628
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	827,248
Operating Properties [Member] | 5250 Eagle Trail Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				952,860
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,638,210
Land and Improvements				952,860
Building and Improvements				3,638,210
Gross Amount Carried at End of Period	4,591,070			4,591,070
Accumulated Depreciation	1,844,262			1,844,262
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,591,070
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,844,262
Operating Properties [Member] | 5501-5519 Pioneer Park Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				162,000
Initial Cost of Buildings				1,613,000
Costs Capitalized Subsequent to Acquisition				1,113,554
Land and Improvements				262,416
Building and Improvements				2,626,138
Gross Amount Carried at End of Period	2,888,554			2,888,554
Accumulated Depreciation	1,526,249			1,526,249
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,888,554
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,526,249
Operating Properties [Member] | 5690-5694 Crenshaw Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				181,923
Initial Cost of Buildings				1,812,496
Costs Capitalized Subsequent to Acquisition				1,023,370
Land and Improvements				181,923
Building and Improvements				2,835,866
Gross Amount Carried at End of Period	3,017,789			3,017,789
Accumulated Depreciation	1,551,921			1,551,921
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,017,789
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,551,921
Operating Properties [Member] | 8110 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				912,663
Initial Cost of Buildings				5,425,143
Costs Capitalized Subsequent to Acquisition				357,492
Land and Improvements				912,663
Building and Improvements				5,782,635
Gross Amount Carried at End of Period	6,695,298			6,695,298
Accumulated Depreciation	1,072,414			1,072,414
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,695,298
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,072,414
Operating Properties [Member] | 8130 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				655,668
Initial Cost of Buildings				4,132,076
Costs Capitalized Subsequent to Acquisition				169,879
Land and Improvements				655,668
Building and Improvements				4,301,955
Gross Amount Carried at End of Period	4,957,623			4,957,623
Accumulated Depreciation	769,863			769,863
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,957,623
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	769,863
Operating Properties [Member] | 9020 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,718,496
Initial Cost of Buildings				11,697,381
Costs Capitalized Subsequent to Acquisition				912,448
Land and Improvements				1,718,496
Building and Improvements				12,609,829
Gross Amount Carried at End of Period	14,328,325			14,328,325
Accumulated Depreciation	2,057,458			2,057,458
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,328,325
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,057,458
Operating Properties [Member] | 9110 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,203,200
Initial Cost of Buildings				7,979,540
Costs Capitalized Subsequent to Acquisition				860,302
Land and Improvements				1,203,200
Building and Improvements				8,839,842
Gross Amount Carried at End of Period	10,043,042			10,043,042
Accumulated Depreciation	1,390,359			1,390,359
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,043,042
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,390,359
Operating Properties [Member] | 9203 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				754,832
Initial Cost of Buildings				4,966,864
Costs Capitalized Subsequent to Acquisition				(22,188)
Land and Improvements				754,832
Building and Improvements				4,944,676
Gross Amount Carried at End of Period	5,699,508			5,699,508
Accumulated Depreciation	760,840			760,840
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,699,508
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	760,840
Operating Properties [Member] | 9319 Peach Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				612,536
Initial Cost of Buildings				4,168,473
Costs Capitalized Subsequent to Acquisition				693,900
Land and Improvements				612,536
Building and Improvements				4,862,373
Gross Amount Carried at End of Period	5,474,909			5,474,909
Accumulated Depreciation	704,408			704,408
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,474,909
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	704,408
Operating Properties [Member] | 9704 Solar Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				374,548
Initial Cost of Buildings				1,354,800
Costs Capitalized Subsequent to Acquisition				969,548
Land and Improvements				374,548
Building and Improvements				2,324,348
Gross Amount Carried at End of Period	2,698,896			2,698,896
Accumulated Depreciation	330,766			330,766
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,698,896
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	330,766
Operating Properties [Member] | 9945 Currie Davis Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,134,286
Initial Cost of Buildings				9,241,807
Costs Capitalized Subsequent to Acquisition				380,833
Land and Improvements				1,134,286
Building and Improvements				9,622,639
Gross Amount Carried at End of Period	10,756,925			10,756,925
Accumulated Depreciation	1,674,500			1,674,500
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,756,925
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,674,500
Operating Properties [Member] | 1858 E Encanto Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				877,611
Initial Cost of Buildings				4,485,427
Costs Capitalized Subsequent to Acquisition				580,036
Land and Improvements				877,611
Building and Improvements				5,065,463
Gross Amount Carried at End of Period	5,943,074			5,943,074
Accumulated Depreciation	924,966			924,966
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,943,074
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	924,966
Operating Properties [Member] | 2040 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,225,000
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				13,156,274
Land and Improvements				3,225,000
Building and Improvements				13,156,274
Gross Amount Carried at End of Period	16,381,274			16,381,274
Accumulated Depreciation	1,043,224			1,043,224
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,381,274
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,043,224
Operating Properties [Member] | 475 W Vaughn St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,112,245
Initial Cost of Buildings				2,260,348
Costs Capitalized Subsequent to Acquisition				392,442
Land and Improvements				1,112,245
Building and Improvements				2,652,790
Gross Amount Carried at End of Period	3,765,035			3,765,035
Accumulated Depreciation	523,937			523,937
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,765,035
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	523,937
Operating Properties [Member] | 921 South Park Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,192,820
Initial Cost of Buildings				1,580,155
Costs Capitalized Subsequent to Acquisition				480,998
Land and Improvements				1,192,820
Building and Improvements				2,061,154
Gross Amount Carried at End of Period	3,253,974			3,253,974
Accumulated Depreciation	557,812			557,812
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,253,974
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	557,812
Operating Properties [Member] | 8313 West Pierce Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,295,090
Initial Cost of Buildings				9,079,811
Costs Capitalized Subsequent to Acquisition				4,105,744
Land and Improvements				2,295,090
Building and Improvements				13,185,555
Gross Amount Carried at End of Period	15,480,645			15,480,645
Accumulated Depreciation	4,599,392			4,599,392
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,480,645
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,599,392
Operating Properties [Member] | 8591 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,574,912
Initial Cost of Buildings				7,308,021
Costs Capitalized Subsequent to Acquisition				547,804
Land and Improvements				1,574,912
Building and Improvements				7,855,825
Gross Amount Carried at End of Period	9,430,737			9,430,737
Accumulated Depreciation	1,379,880			1,379,880
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,430,737
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,379,880
Operating Properties [Member] | 8601 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,524,603
Initial Cost of Buildings				6,352,070
Costs Capitalized Subsequent to Acquisition				855,107
Land and Improvements				1,524,603
Building and Improvements				7,207,177
Gross Amount Carried at End of Period	8,731,780			8,731,780
Accumulated Depreciation	1,374,431			1,374,431
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,731,780
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,374,431
Operating Properties [Member] | 5111 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				435,776
Initial Cost of Buildings				1,875,685
Costs Capitalized Subsequent to Acquisition				533,161
Land and Improvements				435,776
Building and Improvements				2,408,847
Gross Amount Carried at End of Period	2,844,623			2,844,623
Accumulated Depreciation	544,546			544,546
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,844,623
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	544,546
Operating Properties [Member] | 5151 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				345,061
Initial Cost of Buildings				1,428,840
Costs Capitalized Subsequent to Acquisition				321,327
Land and Improvements				345,061
Building and Improvements				1,750,167
Gross Amount Carried at End of Period	2,095,228			2,095,228
Accumulated Depreciation	406,637			406,637
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,095,228
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	406,637
Operating Properties [Member] | Trafalgar house, Temple Court, Daten Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,731,891
Initial Cost of Buildings				11,566,166
Costs Capitalized Subsequent to Acquisition				15,093,255
Land and Improvements				2,731,891
Building and Improvements				12,361,364
Gross Amount Carried at End of Period	15,093,255			15,093,255
Accumulated Depreciation	87,138			87,138
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,093,255
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	87,138
Operating Properties [Member] | 1400 Powis Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				578,314
Initial Cost of Buildings				2,448,562
Costs Capitalized Subsequent to Acquisition				73,377
Land and Improvements				578,314
Building and Improvements				2,521,939
Gross Amount Carried at End of Period	3,100,253			3,100,253
Accumulated Depreciation	409,846			409,846
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,100,253
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	409,846
Operating Properties [Member] | 1 Kings Hill Aveune [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,288,389
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,248,373
Land and Improvements				3,192,636
Building and Improvements				8,344,126
Gross Amount Carried at End of Period	11,536,762			11,536,762
Accumulated Depreciation	2,787,910			2,787,910
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,536,762
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,787,910
Operating Properties [Member] | 42 Kings Hill Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,397,739
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,420,831
Land and Improvements				1,886,646
Building and Improvements				4,931,924
Gross Amount Carried at End of Period	6,818,570			6,818,570
Accumulated Depreciation	1,278,343			1,278,343
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,818,570
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,278,343
Operating Properties [Member] | Liberty Square, Block 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				159,232
Initial Cost of Buildings				1,622,551
Costs Capitalized Subsequent to Acquisition				522,446
Land and Improvements				256,732
Building and Improvements				2,047,498
Gross Amount Carried at End of Period	2,304,230			2,304,230
Accumulated Depreciation	713,693			713,693
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,304,230
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	713,693
Operating Properties [Member] | Liberty Square, Block 2 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				199,150
Initial Cost of Buildings				1,614,217
Costs Capitalized Subsequent to Acquisition				545,985
Land and Improvements				321,094
Building and Improvements				2,038,258
Gross Amount Carried at End of Period	2,359,352			2,359,352
Accumulated Depreciation	685,285			685,285
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,359,352
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	685,285
Operating Properties [Member] | Liberty Square, Block 3 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				129,830
Initial Cost of Buildings				1,141,141
Costs Capitalized Subsequent to Acquisition				381,745
Land and Improvements				209,327
Building and Improvements				1,443,389
Gross Amount Carried at End of Period	1,652,716			1,652,716
Accumulated Depreciation	481,132			481,132
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,652,716
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	481,132
Operating Properties [Member] | Liberty Square, Block 5 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				71,377
Initial Cost of Buildings				735,993
Costs Capitalized Subsequent to Acquisition				236,751
Land and Improvements				115,081
Building and Improvements				929,040
Gross Amount Carried at End of Period	1,044,121			1,044,121
Accumulated Depreciation	309,811			309,811
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,044,121
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	309,811
Operating Properties [Member] | 29 Liberty Square [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				165,363
Initial Cost of Buildings				1,139,928
Costs Capitalized Subsequent to Acquisition				(48,529)
Land and Improvements				159,487
Building and Improvements				1,097,274
Gross Amount Carried at End of Period	1,256,761			1,256,761
Accumulated Depreciation	68,884			68,884
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,256,761
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	68,884
Operating Properties [Member] | 1400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,454,972
Initial Cost of Buildings				5,312,829
Costs Capitalized Subsequent to Acquisition				279,589
Land and Improvements				2,454,972
Building and Improvements				5,592,418
Gross Amount Carried at End of Period	8,047,390			8,047,390
Accumulated Depreciation	1,129,090			1,129,090
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,047,390
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	1,129,090
Operating Properties [Member] | 300 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,177,064
Initial Cost of Buildings				2,102,451
Costs Capitalized Subsequent to Acquisition				160,370
Land and Improvements				1,177,064
Building and Improvements				2,262,821
Gross Amount Carried at End of Period	3,439,885			3,439,885
Accumulated Depreciation	439,188			439,188
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,439,885
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	439,188
Operating Properties [Member] | 400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,029,595
Initial Cost of Buildings				1,728,187
Costs Capitalized Subsequent to Acquisition				183,074
Land and Improvements				1,029,595
Building and Improvements				1,911,261
Gross Amount Carried at End of Period	2,940,856			2,940,856
Accumulated Depreciation	383,082			383,082
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,940,856
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	383,082
Operating Properties [Member] | 6017 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,513,860
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,171,069
Land and Improvements				4,513,860
Building and Improvements				9,171,069
Gross Amount Carried at End of Period	13,684,929			13,684,929
Accumulated Depreciation	268,019			268,019
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,684,929
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	268,019
Operating Properties [Member] | 6035 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,499,894
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,403,466
Land and Improvements				2,499,984
Building and Improvements				5,403,376
Gross Amount Carried at End of Period	7,903,360			7,903,360
Accumulated Depreciation	169,183			169,183
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,903,360
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	169,183
Operating Properties [Member] | 2935 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,682,521
Initial Cost of Buildings				25,905,126
Costs Capitalized Subsequent to Acquisition				1,433,338
Land and Improvements				4,682,521
Building and Improvements				27,338,464
Gross Amount Carried at End of Period	32,020,985			32,020,985
Accumulated Depreciation	4,157,921			4,157,921
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	32,020,985
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	4,157,921
Operating Properties [Member] | 2945 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,345,242
Initial Cost of Buildings				13,973,766
Costs Capitalized Subsequent to Acquisition				245,440
Land and Improvements				2,345,242
Building and Improvements				14,219,206
Gross Amount Carried at End of Period	16,565,448			16,565,448
Accumulated Depreciation	2,102,272			2,102,272
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,565,448
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	2,102,272
Operating Properties [Member] | 43-47 Hintz Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,051,093
Initial Cost of Buildings				18,283,480
Costs Capitalized Subsequent to Acquisition				537,835
Land and Improvements				2,051,093
Building and Improvements				18,821,316
Gross Amount Carried at End of Period	20,872,409			20,872,409
Accumulated Depreciation	3,035,542			3,035,542
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,872,409
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	3,035,542
Operating Properties [Member] | Unit 4, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				843,256
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,787,296
Land and Improvements				1,128,558
Building and Improvements				3,501,994
Gross Amount Carried at End of Period	4,630,552			4,630,552
Accumulated Depreciation	108,001			108,001
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,630,552
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	108,001
Operating Properties [Member] | Unt 3, Plot 163, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,004,097
Initial Cost of Buildings				8,113,667
Costs Capitalized Subsequent to Acquisition				13,079,858
Land and Improvements				4,004,097
Building and Improvements				9,075,761
Gross Amount Carried at End of Period	13,079,858			13,079,858
Accumulated Depreciation	111,591			111,591
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,079,858
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	111,591
Operating Properties [Member] | 2980 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				16,338
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,732,191
Land and Improvements				729,479
Building and Improvements				3,019,050
Gross Amount Carried at End of Period	3,748,529			3,748,529
Accumulated Depreciation	54,419			54,419
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,748,529
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	54,419
Operating Properties [Member] | 11430 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,790,968
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(2,481,843)
Land and Improvements				3,309,125
Building and Improvements				6,088,926
Gross Amount Carried at End of Period	9,398,051			9,398,051
Accumulated Depreciation	69,855			69,855
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,398,051
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	69,855
Operating Properties [Member] | Plot 10A, Worcester Six, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,173,413
Initial Cost of Buildings				12,518,191
Costs Capitalized Subsequent to Acquisition				17,023,085
Land and Improvements				4,173,413
Building and Improvements				12,849,672
Gross Amount Carried at End of Period	17,023,085			17,023,085
Accumulated Depreciation	53,499			53,499
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	17,023,085
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	$ 53,499
Operating Properties [Member] | Maximum
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1467 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1501 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 869 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 901 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8620 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 200 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 250 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 400 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 650 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 651 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 700 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 705 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7165 Ambassador Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7248 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7339 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7437 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8014 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8150 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8250 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8400 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6330 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6350 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6370 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6390 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6520 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6540 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6560 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6580 Snowdrift Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7620 Cetronia Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3095 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3097 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7030 Buford Highway NE [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Barton 150 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1055-1071 Kingsland Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4606 Richlynn Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11800 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11850 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11900 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12104 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12200 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12240 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1071 Thorndale Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1260-1274 Ellis Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 371-377 Meyer Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 350 North York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 850-880 Devon Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10 Emery Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2785 Commerce Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1455 Remington Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 150 E Crossroads Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 553 S Joliet Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 400 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8201 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8451 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 860 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3525 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3535 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Tesco Trucking Station [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 100 Carolina Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 105 Amor Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1485 W Commerce Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 40 Logistics Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 135-195 East Elk Trail [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 515 Kehoe Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1413 Bradley Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3200 Belmeade Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16325 S Avalon Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1475 Nitterhouse Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 95 Kriner Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9000 109th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11701 Goodrich Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12810 Virkler Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2700 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2701 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2730 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2801 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3000 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3005 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4045 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4047 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4525 Statesville Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4835 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4925 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5032 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5033 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5039 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8910 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8916 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8924 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3923 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3929 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2601 Indian River Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1540 S 54th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4650 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4750 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 15025 Proctor Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9645 Gerwig Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2550 John Glenn Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3800 Twin Creeks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5959 Randolph St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 330 South Royal Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 455 Airline Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2130 Baldwin Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11020 Holly Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 329-333 Herrod Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1250 Hall Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 333 Howard Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 131 Aldersgate Street & 14-17 Carthusian Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1680 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1700 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2670 Breckinridge Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 170 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 190 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 265 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 285 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1000 Parliament Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4226 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4227 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4234 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4300 Emperor Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1951 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1953 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1955 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1957 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3169 Dodd Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3711 Kennebec Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 917 Lone Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10301-10305 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10321 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10333 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10349-10357 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10365-10375 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10393-10394 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7075 Flying Cloud Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7078 Shady Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1075 King George Post Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1 Truman Drive South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2250 Arthur Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6600 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6675 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7351 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 21705-21707 Mississippi Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 27143 Elwood International Port Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1800 Donaldson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6880 Fairfield Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7000-7018 Fairfield Business [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10721 Jasmine Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2000 Southpointe Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1400 NW 65th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6500 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6501 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6600 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11222 Melrose Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9601 Cosner Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5410 - 5430 Northwest 33rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12601 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12641 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12681-12691 Pala Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1720 West 135th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 850 S Jupiter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2510 W Main Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4251 North Highway 121 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1150 Pleasant Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 25 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 45 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2011 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2121 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 800 Commerce Parkway West Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 110 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 120 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 130 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 140 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2988 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 125 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2727 London Groveport Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11835 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11841 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1560 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1575 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7361 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7460 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7462 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 500 McCarthy Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 600 Industrial Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7195 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7253 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12537 Cerise Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1010 Petersburg Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 785 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 805 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 825 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 845 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4198 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4183 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4189 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4193 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4328, 4336 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4344 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4380 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4388 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4475 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4485 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4500 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4501 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4523 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4524 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Unit 5 Logix Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1000 South Loop West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10241 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10245 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10301 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10305 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1050 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10607 Haddington Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10735 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10739 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11201 Greens Crossing Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11220 Ella Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1283 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1287 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1291 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1416 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1420 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 14200 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1424 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1428 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 14300 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 14400 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 15102 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 15150 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16330 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16405 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16420 West Hardy Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16445 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1646 Rankin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1655 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16580 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16602 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16605 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1665 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16680 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16685 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1755 Trans Central Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4301 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4401 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4501 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5200 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5250 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5500 N. Sam Houston Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8017 Pinemont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8272 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8282 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8301 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8303 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 850 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 860 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8801-19 & 8821-49 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8802-8824 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8825-8839 N Sam Houston Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8850-8872 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 16200 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5430 FAA Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 951 Valleyview Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Cabot III UK1B01 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1011 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1035 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1549 W Glenlake Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 901 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 925 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8241 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8242 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8246 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 19 Crows Mill Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1305 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1325 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3600 Cobb International Bld NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Unit 1 Bear Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 650 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 680 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1770 Interstate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1200 Claybrick Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1806 Highway 146th South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11425 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11503 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1701 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1801 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1842 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1902 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 640 S State Road 39 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7528 Walker Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8301 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8500 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 875 Maxham Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8742 Congdon Hill Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7533 Industrial Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1169 Canton Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 65 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 75 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 126-132 Liberty Industrial Pkw [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 95-115 Liberty Industrial Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11150 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11250 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11401 NW 134th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11450 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8801 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 11440 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 456 International Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 21 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 230 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 250 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 22750 Cactus Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 323 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 324 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 619 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 627 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 25 Coddington Crescent [Member] [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1775 Hillcrest Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1879 Lamont Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 350 Winmeyer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1 Chadderton Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4000 E Airport Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1000 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10003 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10511 & 10611 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 10771 Palm Bay Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1090 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1600-1650 Central Florida Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1902 Cypress Lake Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2000 Park Oaks Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2202 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2212 Taft Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2256 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2351 Investors Row [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2400 South Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2412 Sand Lake Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2416 Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6918 Presidents Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7022 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7100 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7101 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7315 Kingspointe Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 851 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 950 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9550 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9700 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9600 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1050 Constitution Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1200 Intrepid Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 150 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 201 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 351 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4000 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4020 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4050 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4300 South 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4701 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4751 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4775 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8th & Walnut Streets [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2626 South 7th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 563 South 63rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1500 S 71st Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 7205 W Buckeye Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1000 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1901 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1909 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3605 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3701 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 800 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 900 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9801 80th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 14630-14650 28th Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2920 Northwest Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5905 Trenton Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6055 Nathan Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1400 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1405 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1500 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1501 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1601 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1651 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2201-2215 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2250-2270 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2280-2300 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2301-2329 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3000 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3001-3037 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3012-3050 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 595 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 601 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 605 SW 16th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2459 Almond Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1221 N Alder Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1543 N Alder Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1920 West Baseline Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4101-4127 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4201-4261 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4263-4299 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4263F-N. Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4301-4335 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4337-4379 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4401-4445 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4447-4491 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4501-4549 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4551-4593 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4601-4643 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4645-4683 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4717-4729 Eubank Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 510 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 520 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 530 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 540 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5600-5626 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5601-5659 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5650-5674 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5700 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5701-5799 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5800 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 4 Brittain Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5900 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6000 Eastport Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | St Davids Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6530 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6532 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 13098 George Weber Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 13220 Wilfred Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 13225 Brockton Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1070 Windham Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1550 Central Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9724 Alabama Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1135 Aviation Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5800 Technology Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8715 Bollman Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8501 East Raintree Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1150 Gateway Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5555 12th Avenue East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5651 Innovation Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 12110 Champion Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9300 Old Scotland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3990 Heritage Oak Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3654-3668 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3701 Illinois Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3950-3980 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1501 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1527 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1551 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1 Mirrlees Drive, Hazel Grove [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6900 Harbor View Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6920 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6950 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1516 Fryar Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3401-3409 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3502 Riga Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3505 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 3608 Queen Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5250 Eagle Trail Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5501-5519 Pioneer Park Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5690-5694 Crenshaw Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8110 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8130 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9020 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9110 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9203 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9319 Peach Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9704 Solar Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 9945 Currie Davis Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1850 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1858 E Encanto Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1910 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1930 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2040 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 475 W Vaughn St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 921 South Park Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8313 West Pierce Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8591 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 8601 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5111 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 5151 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Trafalgar house, Temple Court, Daten Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1400 Powis Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1 Kings Hill Aveune [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 42 Kings Hill Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Liberty Square, Block 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Liberty Square, Block 2 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Liberty Square, Block 3 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Liberty Square, Block 5 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 29 Liberty Square [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 1400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 300 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6017 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 6035 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2935 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2945 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 43-47 Hintz Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Worcester 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Unit 4, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Unt 3, Plot 163, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | 2980 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Maximum | Plot 10A, Worcester Six, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	40 years
Operating Properties [Member] | Minimum | 1467 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1501 Perryman Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 869 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 901 S Route 53 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8620 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 200 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 250 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 400 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 650 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 651 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 700 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 705 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7165 Ambassador Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7248 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7339 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7437 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8014 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8150 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8250 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8400 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6330 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6350 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6370 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6390 Hedgewood Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6520 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6540 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6560 Stonegate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6580 Snowdrift Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7620 Cetronia Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2250 East Bardin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3095 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3097 Presidential Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7030 Buford Highway NE [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Barton 150 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1055-1071 Kingsland Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4606 Richlynn Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11800 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11850 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11900 Baltimore Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12104 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12200 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12240 Indian Creek Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1071 Thorndale Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1260-1274 Ellis Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 371-377 Meyer Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 350 North York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 850-880 Devon Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10 Emery Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2785 Commerce Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1455 Remington Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 150 E Crossroads Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 553 S Joliet Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 400 Boulder Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8201 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8451 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 860 Nestle Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3525 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3535 Gravel Springs Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Tesco Trucking Station [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 100 Carolina Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 105 Amor Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1485 W Commerce Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 40 Logistics Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 135-195 East Elk Trail [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 515 Kehoe Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1413 Bradley Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3200 Belmeade Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16325 S Avalon Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1475 Nitterhouse Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 95 Kriner Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9000 109th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11701 Goodrich Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12810 Virkler Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2700 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2701 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2730 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2801 Hutchison McDonald Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3000 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3005 Crosspoint Center Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4045 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4047 Perimeter West Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4525 Statesville Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4835 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4925 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5032 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5033 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5039 Sirona Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8910 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8916 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8924 Pioneer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3923 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3929 Shutterfly Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2601 Indian River Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1540 S 54th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4650 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4750 Lake Forest Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 15025 Proctor Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9645 Gerwig Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2550 John Glenn Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3800 Twin Creeks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5959 Randolph St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 330 South Royal Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 455 Airline Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2130 Baldwin Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11020 Holly Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 329-333 Herrod Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1250 Hall Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 333 Howard Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 131 Aldersgate Street & 14-17 Carthusian Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1680 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1700 Executive Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2670 Breckinridge Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 170 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 190 Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 265 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 285 Parkway East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1000 Parliament Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4226 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4227 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4234 Surles Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4300 Emperor Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1951 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1953 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1955 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1957 TW Alexander Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3169 Dodd Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3711 Kennebec Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 917 Lone Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10301-10305 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10321 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10333 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10349-10357 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10365-10375 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10393-10394 West 70th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7075 Flying Cloud Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7078 Shady Oak Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1075 King George Post Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1 Truman Drive South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2250 Arthur Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6600 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6675 Business Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7351 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 21705-21707 Mississippi Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 27143 Elwood International Port Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1800 Donaldson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6880 Fairfield Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7000-7018 Fairfield Business [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10721 Jasmine Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2000 Southpointe Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1400 NW 65th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6500 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6501 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6600 NW 12th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11222 Melrose Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9601 Cosner Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5410 - 5430 Northwest 33rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12601 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12641 Industry Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12681-12691 Pala Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1720 West 135th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 850 S Jupiter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2510 W Main Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4251 North Highway 121 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1150 Pleasant Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 25 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 45 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2011 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2121 Southtech Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 800 Commerce Parkway West Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 110 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 120 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 130 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 140 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2988 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 125 Caliber Ridge Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2727 London Groveport Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11835 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11841 Newgate Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1560 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1575 Hunter Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7361 Coca Cola Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7460 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7462 New Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 500 McCarthy Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 600 Industrial Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7195 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7253 Grayson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12537 Cerise Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1010 Petersburg Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 785 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 805 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 825 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 845 Lindbergh Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4198 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4183 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4189 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4193 Eagle Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4328, 4336 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4344 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4380 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4388 Federal Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4475 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4485 Premier Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4500 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4501 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4523 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4524 Green Point Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Unit 5 Logix Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1000 South Loop West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10241 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10245 W Little York Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10301 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10305 Round Up Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1050 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10607 Haddington Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10735 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10739 West Little York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11201 Greens Crossing Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11220 Ella Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1283 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1287 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1291 N Post Oak Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1416 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1420 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 14200 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1424 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1428 N Sam Houston Parkway E [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 14300 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 14400 Hollister Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 15102 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 15150 Sommermeyer St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16330 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16405 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16420 West Hardy Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16445 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1646 Rankin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1655 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16580 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16602 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16605 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1665 Townhurst Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16680 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16685 Air Center Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1755 Trans Central Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4301 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4401 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4501 S Pinemont Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5200 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5250 N. Sam Houston Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5500 N. Sam Houston Parkway West [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8017 Pinemont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8272 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8282 El Rio Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8301 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8303 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 850 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 860 Greens Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8801-19 & 8821-49 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8802-8824 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8825-8839 N Sam Houston Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8850-8872 Fallbrook Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 16200 Central Green Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5430 FAA Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 951 Valleyview Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Cabot III UK1B01 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1011 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1035 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1549 W Glenlake Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 901 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 925 N Hilltop Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8241 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8242 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8246 Sandy Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 19 Crows Mill Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1305 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1325 Chastain Road NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3600 Cobb International Bld NW [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Unit 1 Bear Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 650 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 680 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1770 Interstate Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1200 Claybrick Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1806 Highway 146th South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11425 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11503 State Highway 225 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1701 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1801 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1842 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1902 South 16th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 640 S State Road 39 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7528 Walker Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8301 Industrial Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8500 Willard Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 875 Maxham Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8742 Congdon Hill Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7533 Industrial Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1169 Canton Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 65 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 75 Brookfield Oaks Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 126-132 Liberty Industrial Pkw [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 95-115 Liberty Industrial Pkwy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11150 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11250 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11401 NW 134th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11450 NW 122nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8801 Congdon Hill Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11440 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 456 International Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 21 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4 S Middlesex Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 230 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 234 Moonachie Avenue [Member] [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 250 Moonachie Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 22750 Cactus Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 323 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 324 Park Knoll Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 619 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 627 Distribution Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 25 Coddington Crescent [Member] [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1775 Hillcrest Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1879 Lamont Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 350 Winmeyer Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1 Chadderton Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4000 E Airport Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1000 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10003 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10511 & 10611 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 10771 Palm Bay Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1090 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1600-1650 Central Florida Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1902 Cypress Lake Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2000 Park Oaks Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2202 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2212 Taft Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2256 Taft-Vineland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2351 Investors Row [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2400 South Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2412 Sand Lake Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2416 Lake Orange Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6918 Presidents Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7022 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7100 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7101 TPC Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7315 Kingspointe Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 851 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 950 Gills Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9550 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9700 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9600 Satellite Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1050 Constitution Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3 Crescent Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1200 Intrepid Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 150 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 201 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 351 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4000 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4020 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4050 S 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4300 South 26th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4701 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4751 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4775 League Island Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8th & Walnut Streets [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2626 South 7th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 563 South 63rd Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1500 S 71st Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 7205 W Buckeye Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1000 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1901 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1909 10th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3605 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3701 East Plano Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 800 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 900 Klein Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9801 80th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 14630-14650 28th Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2920 Northwest Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5905 Trenton Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6055 Nathan Lane North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1400 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1405 SW 6th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1500 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1501 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1601 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1651 SW 5th Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2201-2215 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2250-2270 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2280-2300 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2301-2329 NW 30th Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3000 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3001-3037 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3012-3050 NW 25th Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 595 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 601 SW 13th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 605 SW 16th Terrace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2459 Almond Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1221 N Alder Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1543 N Alder Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1920 West Baseline Rd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4101-4127 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4201-4261 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4263-4299 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4263F-N. Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4301-4335 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4337-4379 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4401-4445 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4447-4491 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4501-4549 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4551-4593 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4601-4643 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4645-4683 Carolina Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4717-4729 Eubank Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 510 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 520 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 530 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 540 Eastpark Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5600-5626 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5601-5659 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5650-5674 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5700 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5701-5799 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5800 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 4 Brittain Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5900 Eastport Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6000 Eastport Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | St Davids Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6530 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6532 Judge Adams Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 13098 George Weber Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 13220 Wilfred Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 13225 Brockton Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1070 Windham Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1550 Central Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9724 Alabama Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1135 Aviation Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5800 Technology Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8715 Bollman Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8501 East Raintree Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1150 Gateway Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5555 12th Avenue East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5651 Innovation Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 12110 Champion Way [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9300 Old Scotland Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3990 Heritage Oak Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3654-3668 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3701 Illinois Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3950-3980 Swenson Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1501 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1527 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1551 102nd Avenue North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1 Mirrlees Drive, Hazel Grove [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6900 Harbor View Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6920 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6950 Harbour View Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1516 Fryar Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3401-3409 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3502 Riga Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3505 Cragmont Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 3608 Queen Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5250 Eagle Trail Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5501-5519 Pioneer Park Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5690-5694 Crenshaw Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8110 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8130 Anderson Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9020 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9110 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9203 King Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9319 Peach Palm Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9704 Solar Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 9945 Currie Davis Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1850 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1858 E Encanto Dr [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1910 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1930 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2040 W Rio Salado Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 475 W Vaughn St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 921 South Park Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8313 West Pierce Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8591 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 8601 West Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5111 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 5151 S Royal Atlanta Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Trafalgar house, Temple Court, Daten Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1400 Powis Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1 Kings Hill Aveune [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 42 Kings Hill Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Liberty Square, Block 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Liberty Square, Block 2 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Liberty Square, Block 3 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Liberty Square, Block 5 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 29 Liberty Square [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 1400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 300 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 400 Northpoint Parkway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6017 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 6035 Southern Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2935 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2945 West Corporate Lakes Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 43-47 Hintz Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Worcester 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Unit 4, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Unt 3, Plot 163, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 2980 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | 11430 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Operating Properties [Member] | Minimum | Plot 10A, Worcester Six, Pershore Lane [Member]
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life (years)	5 years
Development in Progress [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				186,909,364
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				285,259,659
Land and Improvements				0
Building and Improvements				472,169,022
Gross Amount Carried at End of Period	$ 472,169,022			472,169,022
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	472,169,022
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 350 North York Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,043,130
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,507,853
Land and Improvements				0
Building and Improvements				4,550,983
Gross Amount Carried at End of Period	4,550,983			4,550,983
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,550,983
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 650 Swedesford Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				488,529
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,065,131
Land and Improvements				0
Building and Improvements				4,553,660
Gross Amount Carried at End of Period	4,553,660			4,553,660
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,553,660
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 3535 N Houston School Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,014,293
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				48,978,234
Land and Improvements				0
Building and Improvements				53,992,527
Gross Amount Carried at End of Period	53,992,527			53,992,527
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	53,992,527
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1912 16th St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,337,516
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				365,516
Land and Improvements				0
Building and Improvements				1,703,032
Gross Amount Carried at End of Period	1,703,032			1,703,032
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,703,032
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 160 and 180 Dulty's Lane Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,920,365
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,133,984
Land and Improvements				0
Building and Improvements				16,054,349
Gross Amount Carried at End of Period	16,054,349			16,054,349
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	16,054,349
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 12830 Virklet Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				298,624
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,283,630
Land and Improvements				0
Building and Improvements				4,582,253
Gross Amount Carried at End of Period	4,582,253			4,582,253
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,582,253
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | Widnes - Unit 1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				703,253
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,413,864
Land and Improvements				0
Building and Improvements				3,117,117
Gross Amount Carried at End of Period	3,117,117			3,117,117
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,117,117
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 2980 Green Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				16,338
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,183,126
Land and Improvements				0
Building and Improvements				2,199,464
Gross Amount Carried at End of Period	2,199,464			2,199,464
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,199,464
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 7157 Ridge Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,875,203
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				17,667,379
Land and Improvements				0
Building and Improvements				21,542,582
Gross Amount Carried at End of Period	21,542,582			21,542,582
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,542,582
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1401 Rankin Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,895,650
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,628,113
Land and Improvements				0
Building and Improvements				18,523,763
Gross Amount Carried at End of Period	18,523,763			18,523,763
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	18,523,763
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 15515 Woodham Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				21,665,705
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				28,161,131
Land and Improvements				0
Building and Improvements				49,826,836
Gross Amount Carried at End of Period	49,826,836			49,826,836
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	49,826,836
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 5350 Frye Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,589,923
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,726,004
Land and Improvements				0
Building and Improvements				12,315,927
Gross Amount Carried at End of Period	12,315,927			12,315,927
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,315,927
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 120 Midway Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,410,100
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				24,034,026
Land and Improvements				0
Building and Improvements				29,444,126
Gross Amount Carried at End of Period	29,444,126			29,444,126
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	29,444,126
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1814 Highway 146th South [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,420,014
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				5,688,787
Land and Improvements				0
Building and Improvements				7,108,801
Gross Amount Carried at End of Period	7,108,801			7,108,801
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,108,801
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1302 Wharton Weems Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,378,890
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				22,599,236
Land and Improvements				0
Building and Improvements				26,978,126
Gross Amount Carried at End of Period	26,978,126			26,978,126
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	26,978,126
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1901 Wharton Weems Blvd [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,634,375
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				435,322
Land and Improvements				0
Building and Improvements				3,069,697
Gross Amount Carried at End of Period	3,069,697			3,069,697
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,069,697
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 11230 Nw 122 St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,226,348
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,823,058
Land and Improvements				0
Building and Improvements				12,049,406
Gross Amount Carried at End of Period	12,049,406			12,049,406
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,049,406
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 11240 NW 122 St [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,226,348
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				10,261,112
Land and Improvements				0
Building and Improvements				15,487,460
Gross Amount Carried at End of Period	15,487,460			15,487,460
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,487,460
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 11430 NW 122 Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,790,968
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,257,013
Land and Improvements				0
Building and Improvements				7,047,981
Gross Amount Carried at End of Period	7,047,981			7,047,981
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	7,047,981
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | Liberty 196 Brackmills [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,272,742
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,991,279
Land and Improvements				0
Building and Improvements				20,264,021
Gross Amount Carried at End of Period	20,264,021			20,264,021
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	20,264,021
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 2300 Liberty Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				9,549,414
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,247,326
Land and Improvements				0
Building and Improvements				10,796,740
Gross Amount Carried at End of Period	10,796,740			10,796,740
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	10,796,740
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 2800 Liberty Drive [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,478,785
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				342,628
Land and Improvements				0
Building and Improvements				11,821,413
Gross Amount Carried at End of Period	11,821,413			11,821,413
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,821,413
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1383 S Cucamonga Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,773,327
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,249,141
Land and Improvements				0
Building and Improvements				8,022,468
Gross Amount Carried at End of Period	8,022,468			8,022,468
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	8,022,468
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 400 Rouse Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				10,514,720
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,088,179
Land and Improvements				0
Building and Improvements				12,602,899
Gross Amount Carried at End of Period	12,602,899			12,602,899
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	12,602,899
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 1250 S 71st Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,587,584
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				10,854,851
Land and Improvements				0
Building and Improvements				14,442,435
Gross Amount Carried at End of Period	14,442,435			14,442,435
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,442,435
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 2000 W Baseline Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				11,706,478
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				11,142,119
Land and Improvements				0
Building and Improvements				22,848,597
Gross Amount Carried at End of Period	22,848,597			22,848,597
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	22,848,597
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 855 W Valley Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				24,722,726
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,779,395
Land and Improvements				0
Building and Improvements				27,502,121
Gross Amount Carried at End of Period	27,502,121			27,502,121
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	27,502,121
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 520 East Orange Shadow Road [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				14,742,703
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				16,750,766
Land and Improvements				0
Building and Improvements				31,493,469
Gross Amount Carried at End of Period	31,493,469			31,493,469
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	31,493,469
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 42 Kings Hill Ave [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,237,847
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				8,358,786
Land and Improvements				0
Building and Improvements				9,596,633
Gross Amount Carried at End of Period	9,596,633			9,596,633
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	9,596,633
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | 6043 Southern Boulevard [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,741,040
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				3,382,226
Land and Improvements				0
Building and Improvements				6,123,266
Gross Amount Carried at End of Period	6,123,266			6,123,266
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,123,266
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Development in Progress [Member] | Worcester Plot 2A [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				646,426
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,860,444
Land and Improvements				0
Building and Improvements				2,506,870
Gross Amount Carried at End of Period	2,506,870			2,506,870
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,506,870
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				224,063,793
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				72,180,087
Land and Improvements				296,243,880
Building and Improvements				0
Gross Amount Carried at End of Period	296,243,880			296,243,880
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	296,243,880
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Camden Town Center Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,384,543
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(1,815,511)
Land and Improvements				1,569,032
Building and Improvements				0
Gross Amount Carried at End of Period	1,569,032			1,569,032
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,569,032
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Randolph Street Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				1,758,528
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				0
Land and Improvements				1,758,528
Building and Improvements				0
Gross Amount Carried at End of Period	1,758,528			1,758,528
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,758,528
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Mountain Creek Business Park L [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				7,984,928
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				6,952,870
Land and Improvements				14,937,798
Building and Improvements				0
Gross Amount Carried at End of Period	14,937,798			14,937,798
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	14,937,798
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | 4030 S State Road 7 Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				14,727,819
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				488,777
Land and Improvements				15,216,596
Building and Improvements				0
Gross Amount Carried at End of Period	15,216,596			15,216,596
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	15,216,596
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Holly Lane North Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				889,205
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				143,710
Land and Improvements				1,032,915
Building and Improvements				0
Gross Amount Carried at End of Period	1,032,915			1,032,915
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,032,915
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | French Lake Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				13,513,632
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				7,684,117
Land and Improvements				21,197,749
Building and Improvements				0
Gross Amount Carried at End of Period	21,197,749			21,197,749
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,197,749
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Flying Cloud Drive Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,051,631
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,949,097
Land and Improvements				4,000,728
Building and Improvements				0
Gross Amount Carried at End of Period	4,000,728			4,000,728
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,000,728
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Camelback 303 Business Center Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				16,857,556
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,435,684
Land and Improvements				21,293,240
Building and Improvements				0
Gross Amount Carried at End of Period	21,293,240			21,293,240
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	21,293,240
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Pleasant Ridge Road Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				564,535
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,931,704
Land and Improvements				3,496,239
Building and Improvements				0
Gross Amount Carried at End of Period	3,496,239			3,496,239
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,496,239
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Ridge Road Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,371,183
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(583,887)
Land and Improvements				2,787,296
Building and Improvements				0
Gross Amount Carried at End of Period	2,787,296			2,787,296
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,787,296
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Interwood Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,160,668
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				32,647
Land and Improvements				5,193,315
Building and Improvements				0
Gross Amount Carried at End of Period	5,193,315			5,193,315
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,193,315
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Richey Road Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				12,630,951
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(11,522,400)
Land and Improvements				1,108,551
Building and Improvements				0
Gross Amount Carried at End of Period	1,108,551			1,108,551
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	1,108,551
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Cabin Branch Road Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				507,337
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,851,968
Land and Improvements				2,359,305
Building and Improvements				0
Gross Amount Carried at End of Period	2,359,305			2,359,305
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,359,305
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Kent County, UK [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				0
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				24,724,274
Land and Improvements				24,724,274
Building and Improvements				0
Gross Amount Carried at End of Period	24,724,274			24,724,274
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	24,724,274
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Port Crossing Commerce Center Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				5,073,341
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				316,899
Land and Improvements				5,390,240
Building and Improvements				0
Gross Amount Carried at End of Period	5,390,240			5,390,240
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,390,240
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Commodore Business Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				792,118
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,456,064
Land and Improvements				2,248,182
Building and Improvements				0
Gross Amount Carried at End of Period	2,248,182			2,248,182
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	2,248,182
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Paramount Boulevard Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				33,689,684
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				197,422
Land and Improvements				33,887,106
Building and Improvements				0
Gross Amount Carried at End of Period	33,887,106			33,887,106
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	33,887,106
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Spring Creek Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				36,615,601
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				12,137,495
Land and Improvements				48,753,096
Building and Improvements				0
Gross Amount Carried at End of Period	48,753,096			48,753,096
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	48,753,096
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Miami International Tradeport Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				8,359,177
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				9,001,589
Land and Improvements				17,360,766
Building and Improvements				0
Gross Amount Carried at End of Period	17,360,766			17,360,766
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	17,360,766
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | 557 Nazareth Pike Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,667,646
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				668,506
Land and Improvements				5,336,152
Building and Improvements				0
Gross Amount Carried at End of Period	5,336,152			5,336,152
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	5,336,152
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | 357 Wilson Avenue Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				12,882,076
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				145,473
Land and Improvements				13,027,549
Building and Improvements				0
Gross Amount Carried at End of Period	13,027,549			13,027,549
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	13,027,549
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Century Commerce Center Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				17,347,131
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				1,915,008
Land and Improvements				19,262,139
Building and Improvements				0
Gross Amount Carried at End of Period	19,262,139			19,262,139
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	19,262,139
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Southern Boulevard Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				6,628,239
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				4,838,777
Land and Improvements				11,467,016
Building and Improvements				0
Gross Amount Carried at End of Period	11,467,016			11,467,016
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	11,467,016
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Buckeye Logistics Center West Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,193,865
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				2,331,154
Land and Improvements				6,525,019
Building and Improvements				0
Gross Amount Carried at End of Period	6,525,019			6,525,019
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	6,525,019
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Walkins Street and 48th Avenue Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				4,078,812
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				247,597
Land and Improvements				4,326,409
Building and Improvements				0
Gross Amount Carried at End of Period	4,326,409			4,326,409
Accumulated Depreciation
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,326,409
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation
Land Held for Development | Woodlands Center Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				148,314
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				21,717
Land and Improvements				170,031
Building and Improvements				0
Gross Amount Carried at End of Period	170,031			170,031
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	170,031
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Suffolk Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				2,715,714
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				823,895
Land and Improvements				3,539,609
Building and Improvements				0
Gross Amount Carried at End of Period	3,539,609			3,539,609
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	3,539,609
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | 6119 W. Linebaugh Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				180,136
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				(105,136)
Land and Improvements				75,000
Building and Improvements				0
Gross Amount Carried at End of Period	75,000			75,000
Accumulated Depreciation	0			0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	75,000
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	0
Land Held for Development | Legacy Park Land [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				0
Initial Cost of Land				3,289,423
Initial Cost of Buildings				0
Costs Capitalized Subsequent to Acquisition				910,577
Land and Improvements				4,200,000
Building and Improvements				0
Gross Amount Carried at End of Period	4,200,000			4,200,000
Accumulated Depreciation	0			$ 0
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real Estate, Gross	4,200,000
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Real Estate Accumulated Depreciation	$ 0