Gramercy Property Trust 10-Q 1 May 18 2018 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 27, 2018
Document Information [Line Items]
Entity Registrant Name	Gramercy Property Trust
Entity Central Index Key	1,297,587
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	gpt
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		160,785,498
GPT Operating Partnership LP
Document Information [Line Items]
Entity Registrant Name	GPT Operating Partnership LP
Entity Central Index Key	1,708,204
Entity Filer Category	Non-accelerated Filer

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Real estate investments, at cost:
Land	$ 1,009,568	$ 1,023,908
Building and improvements	4,821,301	4,863,916
Less: accumulated depreciation	(368,815)	(333,151)
Total real estate investments, net	5,462,054	5,554,673
Cash and cash equivalents	41,964	30,231
Restricted cash	15,041	12,723
Investment in unconsolidated equity investments	99,113	70,214
Assets held for sale, net	402	402
Tenant and other receivables, net	92,525	88,750
Acquired lease assets, net of accumulated amortization of $241,939 and $220,473	563,213	598,559
Other assets	127,664	100,484
Total assets	6,401,976	6,456,036
Liabilities:
Senior unsecured revolving credit facility	292,543	357,162
Mortgage notes payable, net	559,473	563,521
Total long-term debt, net	2,797,144	2,865,620
Accounts payable and accrued expenses	60,151	59,619
Dividends payable	62,380	61,971
Below market lease liabilities, net of accumulated amortization of $31,201 and $28,978	159,544	166,491
Other liabilities	55,873	50,002
Total liabilities	3,135,092	3,203,703
Commitments and contingencies
Noncontrolling interest in the Operating Partnership	137,800	113,530
Equity:
Common shares, par value $0.01, 160,782,765 and 160,686,822 issued and outstanding at March 31, 2018 and December 31, 2017, respectively	1,608	1,607
Series A cumulative redeemable preferred shares, par value $0.01, liquidation preference $87,500, and 3,500,000 shares authorized, issued and outstanding at March 31, 2018 and December 31, 2017	84,394	84,394
Additional paid-in-capital	4,411,605	4,409,677
Accumulated other comprehensive income	35,667	12,776
Accumulated deficit	(1,404,416)	(1,369,872)
Total shareholders' equity	3,128,858	3,138,582
Noncontrolling interest in other entities	226	221
Total equity	3,129,084	3,138,803
Partners’ Capital:
Accumulated other comprehensive loss	35,667	12,776
Total liabilities and equity	6,401,976	6,456,036
Senior unsecured notes, net [Member]
Liabilities:
Unsecured debt	496,887	496,785
Senior unsecured term loans
Liabilities:
Unsecured debt	1,448,241	1,448,152
GPT Operating Partnership LP
Real estate investments, at cost:
Land	1,009,568	1,023,908
Building and improvements	4,821,301	4,863,916
Less: accumulated depreciation	(368,815)	(333,151)
Total real estate investments, net	5,462,054	5,554,673
Cash and cash equivalents	41,964	30,231
Restricted cash	15,041	12,723
Investment in unconsolidated equity investments	99,113	70,214
Assets held for sale, net	402	402
Tenant and other receivables, net	92,525	88,750
Acquired lease assets, net of accumulated amortization of $241,939 and $220,473	563,213	598,559
Other assets	127,664	100,484
Total assets	6,401,976	6,456,036
Liabilities:
Senior unsecured revolving credit facility	292,543	357,162
Mortgage notes payable, net	559,473	563,521
Total long-term debt, net	2,797,144	2,865,620
Accounts payable and accrued expenses	60,151	59,619
Dividends payable	62,380	61,971
Below market lease liabilities, net of accumulated amortization of $31,201 and $28,978	159,544	166,491
Other liabilities	55,873	50,002
Total liabilities	3,135,092	3,203,703
Commitments and contingencies
Noncontrolling interest in the Operating Partnership	137,800	113,530
Equity:
Accumulated other comprehensive income	35,667	12,776
Partners’ Capital:
Series A cumulative redeemable preferred units, liquidation preference $87,500, and 3,500,000 units issued and outstanding at March 31, 2018 and December 31, 2017	84,394	84,394
GPT partners’ capital (1,658,060 and 1,650,858 general partner common units and 159,124,705 and 159,035,964 limited partner common units outstanding at March 31, 2018 and December 31, 2017, respectively)	3,008,797	3,041,412
Accumulated other comprehensive loss	35,667	12,776
Total GPTOP partners' capital	3,128,858	3,138,582
Noncontrolling interest in other entities	226	221
Total partners’ capital	3,129,084	3,138,803
Total liabilities and equity	6,401,976	6,456,036
GPT Operating Partnership LP | Senior unsecured notes, net [Member]
Liabilities:
Unsecured debt	496,887	496,785
GPT Operating Partnership LP | Senior unsecured term loans
Liabilities:
Unsecured debt	$ 1,448,241	$ 1,448,152

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquired lease assets, accumulated amortization (in dollars)	$ 241,939	$ 220,473
Below market lease liabilities, accumulated amortization (in dollars)	$ 31,201	$ 28,978
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares issued	160,782,765	160,686,822
Common stock, shares outstanding	160,782,765	160,686,822
Cumulative redeemable preferred stock, shares authorized	10,000,000	10,000,000
Cumulative redeemable preferred stock, shares outstanding	3,500,000
Series A Preferred Stock
Cumulative redeemable preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Cumulative redeemable preferred stock, liquidation preference (in dollars)	$ 87,500	$ 87,500
Cumulative redeemable preferred stock, shares authorized	3,500,000	3,500,000
Cumulative redeemable preferred stock, shares issued	3,500,000	3,500,000
Cumulative redeemable preferred stock, shares outstanding	3,500,000	3,500,000
GPT Operating Partnership LP
Acquired lease assets, accumulated amortization (in dollars)	$ 241,939	$ 220,473
Below market lease liabilities, accumulated amortization (in dollars)	31,201	28,978
Series A cumulative redeemable preferred units, liquidation preference (in dollars)	$ 87,500	$ 87,500
Series A cumulative redeemable preferred units, units issued	3,500,000	3,500,000
Series A cumulative redeemable preferred units, units outstanding	3,500,000	3,500,000
General partners' capital, units issued	1,658,060	1,650,858
Limited partners' capital, units issued	159,124,705	159,035,964
General partners' capital, units outstanding	1,658,060	1,650,858
Limited partners' capital, units outstanding	159,124,705	159,035,964
Noncontrolling Interest | GPT Operating Partnership LP
Limited partners' capital, units outstanding	5,388,995	4,398,935

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Rental revenue	$ 122,245	$ 103,282
Operating expense reimbursements	23,310	20,368
Third-party management fees	2,790	4,592
Other income	1,135	1,752
Total revenues	149,480	129,994
Operating Expenses
Depreciation and amortization	71,516	62,217
Property operating expenses	27,088	23,186
General and administrative expenses	9,686	8,756
Property management expenses	2,542	3,084
Total operating expenses	110,832	97,243
Operating income	38,648	32,751
Other Expenses:
Interest expense	(25,492)	(23,056)
Other-than-temporary impairment	0	(4,081)
Portion of impairment recognized in other comprehensive loss	0	(809)
Net impairment recognized in earnings	0	(4,890)
Equity in net loss of unconsolidated equity investments	(926)	(94)
Loss on extinguishment of debt	0	(208)
Impairment of real estate investments	0	(12,771)
Income (loss) from continuing operations before provision for taxes	12,230	(8,268)
Provision for taxes	(621)	196
Income (loss) from continuing operations	11,609	(8,072)
Loss from discontinued operations	0	(24)
Net income (loss) before net gain on disposals	11,609	(8,096)
Net gain on disposals	16,255	17,377
Net income	27,864	9,281
Net income attributable to noncontrolling interest	(802)	(154)
Net income attributable to Gramercy Property Trust	27,062	9,127
Preferred share dividends	(1,559)	(1,559)
Net income available to common shareholders	$ 25,503	$ 7,568
Basic earnings per share:
Net income from continuing operations, after preferred dividends (in usd per share)	$ 0.16	$ 0.05
Net income (loss) from discontinued operations (in usd per share)	0	0
Net income available to common stockholders (in usd per share)	0.16	0.05
Diluted earnings per share:
Net income from continuing operations, after preferred dividends (in usd per share)	0.16	0.05
Net income (loss) from discontinued operations (in usd per share)	0	0
Net income available to common stockholders (in usd per share)	$ 0.16	$ 0.05
Basic weighted average common shares outstanding (in shares)	160,408,136	140,907,399
Diluted weighted average common shares and common share equivalents outstanding (in shares)	160,416,900	141,875,619
GPT Operating Partnership LP
Revenues
Rental revenue	$ 122,245	$ 103,282
Operating expense reimbursements	23,310	20,368
Third-party management fees	2,790	4,592
Other income	1,135	1,752
Total revenues	149,480	129,994
Operating Expenses
Depreciation and amortization	71,516	62,217
Property operating expenses	27,088	23,186
General and administrative expenses	9,686	8,756
Property management expenses	2,542	3,084
Total operating expenses	110,832	97,243
Operating income	38,648	32,751
Other Expenses:
Interest expense	(25,492)	(23,056)
Other-than-temporary impairment	0	(4,081)
Portion of impairment recognized in other comprehensive loss	0	(809)
Net impairment recognized in earnings	0	(4,890)
Equity in net loss of unconsolidated equity investments	(926)	(94)
Loss on extinguishment of debt	0	(208)
Impairment of real estate investments	0	(12,771)
Income (loss) from continuing operations before provision for taxes	12,230	(8,268)
Provision for taxes	(621)	196
Income (loss) from continuing operations	11,609	(8,072)
Loss from discontinued operations	0	(24)
Net income (loss) before net gain on disposals	11,609	(8,096)
Net gain on disposals	16,255	17,377
Net income	27,864	9,281
Net income attributable to noncontrolling interest in other partnerships	0	(120)
Net income attributable to Gramercy Property Trust	27,864	9,161
Preferred share dividends	(1,559)	(1,559)
Net income available to common unitholders	$ 26,305	$ 7,602
Basic earnings per unit:
Net income from continuing operations, after preferred unit distributions basic (in usd per unit)	$ 0.16	$ 0.05
Net income (loss) from discontinued operations, basic (in usd per unit)	0	0
Net income available to common unitholders, basic (in usd per unit)	0.16	0.05
Diluted earnings per unit:
Net income from continuing operations, after preferred unit distributions, diluted (in usd per unit)	0.16	0.05
Net income (loss) from discontinued operations, diluted (in usd per unit)	0	0
Net income available to common unitholders, diluted (in usd per unit)	$ 0.16	$ 0.05
Basic weighted average common units outstanding (in units)	165,448,866	141,527,985
Diluted weighted average common units outstanding (in units)	165,457,630	142,496,205

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net income	$ 27,864	$ 9,281
Other comprehensive income (loss):
Unrealized loss on available for sale debt securities	(48)	(2,820)
Cumulative effect of accounting change	103	0
Unrealized gain on derivative instruments	22,050	4,378
Reclassification of unrealized gain on terminated derivative instruments into earnings	268	268
Foreign currency translation adjustments	518	691
Other comprehensive income	22,891	2,517
Comprehensive income	50,755	11,798
Net income attributable to noncontrolling interest	(802)	(154)
Other comprehensive (income) loss attributable to noncontrolling interest	697	(11)
Comprehensive income attributable to Gramercy Property Trust	50,650	11,633
GPT Operating Partnership LP
Net income	27,864	9,281
Other comprehensive income (loss):
Unrealized loss on available for sale debt securities	(48)	(2,820)
Cumulative effect of accounting change	103	0
Unrealized gain on derivative instruments	22,050	4,378
Reclassification of unrealized gain on terminated derivative instruments into earnings	268	268
Foreign currency translation adjustments	518	691
Other comprehensive income	22,891	2,517
Comprehensive income	50,755	11,798
Net income attributable to noncontrolling interest in other partnerships	0	(120)
Comprehensive income attributable to Gramercy Property Trust	$ 50,755	$ 11,678

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Shareholders' Equity (Deficit) and Noncontrolling Interests - USD ($) $ in Thousands	Total	Total Gramercy Property Trust	Common Shares	Preferred Shares	Additional Paid-In-Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings / (Accumulated Deficit)	Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting changes	$ 663	$ 663				$ 103	$ 560
Balance (in shares) at Dec. 31, 2017	160,686,822		160,686,822
Balance at Dec. 31, 2017	$ 3,138,803	3,138,582	$ 1,607	$ 84,394	$ 4,409,677	12,776	(1,369,872)	$ 221
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,062	27,062					27,062	0
Change in net unrealized gain on derivative instruments	22,050	22,050				22,050
Change in net unrealized loss on debt securities	(48)	(48)				(48)
Reclassification of unrealized gain on terminated derivative instruments into earnings	268	268				268
Offering costs	(39)	(39)			(39)
Share based compensation - fair value (in shares)			88,094
Share based compensation - fair value	$ 2,024	2,024	$ 1		2,023
Dividend reinvestment program proceeds (in shares)	1,811		1,811
Dividend reinvestment program proceeds	$ 46	46			46
Conversion of OP Units to commons shares (in shares)			6,038
Conversion of OP Units to common shares	130	130	$ 0		130
Reallocation of noncontrolling interest in the Operating Partnership	(232)	(232)			(232)
Other Comprehensive Income (Loss), Foreign Currency Transaction And Translation Gain (Loss) Arising During Period, Including Portion Attributable To NCI, Net Of Tax	518	518				518		0
Contributions to noncontrolling interest in other partnerships	5							5
Dividends on preferred shares	(1,559)	(1,559)					(1,559)
Dividends on common shares	$ (60,607)	(60,607)					(60,607)
Balance (in shares) at Mar. 31, 2018	160,782,765		160,782,765
Balance at Mar. 31, 2018	$ 3,129,084	$ 3,128,858	$ 1,608	$ 84,394	$ 4,411,605	$ 35,667	$ (1,404,416)	$ 226

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Partners' Capital - USD ($) $ in Thousands	Total	GPT Operating Partnership LP	GPT Operating Partnership LPTotal GPTOP	GPT Operating Partnership LPPartners' Interest	GPT Operating Partnership LPSeries A Preferred Units	GPT Operating Partnership LPAccumulated Other Comprehensive Income (Loss)	GPT Operating Partnership LPNoncontrolling Interest
Increase (Decrease) in Partners' Capital [Roll Forward]
Cumulative effect of accounting changes	$ 663	$ 663	$ 663	$ 560		$ 103
Beginning balance (in units) at Dec. 31, 2017				160,686,822
Beginning balance at Dec. 31, 2017		3,138,803	3,138,582	$ 3,041,412	$ 84,394	12,776	$ 221
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	27,062	27,062	27,062	27,062			0
Change in net unrealized gain on derivative instruments	22,050	22,050	22,050			22,050
Change in net unrealized loss on debt securities	(48)	(48)	(48)			(48)
Reclassification of unrealized gain on terminated derivative instruments into earnings	268	268	268			268
Offering costs		(39)	(39)	$ (39)
Share based compensation - fair value (in units)				88,094
Share based compensation - fair value		2,024	2,024	$ 2,024
Distribution reinvestment program proceeds (in units)				1,811
Distribution reinvestment program proceeds		46	46	$ 46
Conversion of OP Units to common unit (in units)				6,038
Conversion of OP Units to common units		130	130	$ 130
Reallocation of noncontrolling interest in the Operating Partnership	(232)	(232)	(232)	(232)
Foreign currency translation adjustment		518	518			518	0
Contributions to noncontrolling interest in other partnerships	$ 5	5					$ 5
Distributions on preferred units		(1,559)	(1,559)	(1,559)
Distributions on common units		$ (60,607)	(60,607)	$ (60,607)
Ending balance (in units) at Mar. 31, 2018		160,782,765		160,782,765			5,388,995
Ending balance at Mar. 31, 2018		$ 3,129,084	$ 3,128,858	$ 3,008,797	$ 84,394	$ 35,667	$ 226

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating Activities:
Net income	$ 27,864	$ 9,281
Adjustments to net cash provided by operating activities:
Depreciation and amortization	71,516	62,217
Amortization of market lease intangibles	(392)	(547)
Amortization of deferred costs	825	615
Amortization of discounts and other fees	(632)	(409)
Straight-line rent adjustment	(7,025)	(7,260)
Other-than-temporary impairment on retained bonds	0	4,890
Impairment of real estate investments	0	12,771
Net gain on disposals	(16,255)	(17,377)
Distributions received from unconsolidated equity investments	0	352
Equity in net loss of unconsolidated equity investments	926	94
Loss on extinguishment of debt	0	208
Amortization of share-based compensation	1,856	2,054
Changes in operating assets and liabilities:
Payment of capitalized leasing costs	(4,526)	(3,790)
Tenant and other receivables	3,253	11,707
Other assets	(1,401)	(4,368)
Accounts payable and accrued expenses	(8,050)	(9,755)
Other liabilities	4,864	(2,204)
Net cash provided by operating activities	72,823	58,479
Investing Activities:
Capital expenditures	(17,825)	(18,429)
Proceeds from sales of real estate	108,032	33,053
Contributions to unconsolidated equity investments	(5,856)	(2,650)
Acquisition of real estate	(10,971)	(99,612)
Net cash provided by (used in) investing activities	73,380	(87,638)
Financing Activities:
Proceeds from unsecured term loan and credit facility	164,922	60,000
Repayment of unsecured term loans and credit facility	(230,000)	(5,000)
Proceeds from mortgage notes payable	0	2,582
Repayment of mortgage notes payable	(3,545)	(3,915)
Offering costs	0	(606)
Proceeds from sale of common shares	0	20,081
Payment of deferred financing costs	0	(252)
Preferred share dividends paid	(1,559)	(1,559)
Common share dividends paid	(60,568)	(53,025)
Distribution to noncontrolling interest in the Operating Partnership	(1,402)	(118)
Other financing activities	(138)	0
Net cash provided by (used in) financing activities	(132,290)	18,188
Net increase (decrease) in cash, cash equivalents, and restricted cash	13,913	(10,971)
Increase (decrease) in cash, cash equivalents, and restricted cash related to foreign currency translation	138	(105)
Cash, cash equivalents, and restricted cash at beginning of period	42,954	80,433
Cash, cash equivalents, and restricted cash at end of period	57,005	69,357
GPT Operating Partnership LP
Operating Activities:
Net income	27,864	9,281
Adjustments to net cash provided by operating activities:
Depreciation and amortization	71,516	62,217
Amortization of market lease intangibles	(392)	(547)
Amortization of deferred costs	825	615
Amortization of discounts and other fees	(632)	(409)
Straight-line rent adjustment	(7,025)	(7,260)
Other-than-temporary impairment on retained bonds	0	4,890
Impairment of real estate investments	0	12,771
Net gain on disposals	(16,255)	(17,377)
Distributions received from unconsolidated equity investments	0	352
Equity in net loss of unconsolidated equity investments	926	94
Loss on extinguishment of debt	0	208
Amortization of share-based compensation	1,856	2,054
Changes in operating assets and liabilities:
Payment of capitalized leasing costs	(4,526)	(3,790)
Tenant and other receivables	3,253	11,707
Other assets	(1,401)	(4,368)
Accounts payable and accrued expenses	(8,050)	(9,755)
Other liabilities	4,864	(2,204)
Net cash provided by operating activities	72,823	58,479
Investing Activities:
Capital expenditures	(17,825)	(18,429)
Proceeds from sales of real estate	108,032	33,053
Contributions to unconsolidated equity investments	(5,856)	(2,650)
Acquisition of real estate	(10,971)	(99,612)
Net cash provided by (used in) investing activities	73,380	(87,638)
Financing Activities:
Proceeds from unsecured term loan and credit facility	164,922	60,000
Repayment of unsecured term loans and credit facility	(230,000)	(5,000)
Proceeds from mortgage notes payable	0	2,582
Repayment of mortgage notes payable	(3,545)	(3,915)
Offering costs	0	(606)
Proceeds from sale of common shares	0	20,081
Payment of deferred financing costs	0	(252)
Preferred share dividends paid	(1,559)	(1,559)
Common share dividends paid	(60,568)	(53,025)
Distribution to noncontrolling interest in the Operating Partnership	(1,402)	(118)
Other financing activities	(138)	0
Net cash provided by (used in) financing activities	(132,290)	18,188
Net increase (decrease) in cash, cash equivalents, and restricted cash	13,913	(10,971)
Increase (decrease) in cash, cash equivalents, and restricted cash related to foreign currency translation	138	(105)
Cash, cash equivalents, and restricted cash at beginning of period	42,954	80,433
Cash, cash equivalents, and restricted cash at end of period	$ 57,005	$ 69,357

Business and Organization

Business and Organization	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization	Business and Organization Gramercy Property Trust, or the Company or Gramercy, a Maryland real estate investment trust, or REIT, together with its subsidiary, GPT Operating Partnership LP, or the Operating Partnership, is a leading global investor and asset manager of commercial real estate. Gramercy specializes in acquiring and managing high quality, income producing commercial real estate leased to high quality tenants in major markets in the United States and Europe. Gramercy earns revenues primarily through rental revenues on properties that it owns in the United States. The Company also owns unconsolidated equity investments in the United States, Europe, and Asia. The Company's operations are conducted primarily through the Operating Partnership. As of March 31, 2018 , third-party holders of limited partnership interests owned approximately 3.25% of the Operating Partnership. These interests are referred to as the noncontrolling interests in the Operating Partnership. See Note 11 for more information on the Company’s noncontrolling interests. As of March 31, 2018 , the Company’s wholly-owned portfolio consisted of 362 properties comprising 80,884,942 rentable square feet with 97.3% occupancy. As of March 31, 2018 , the Company had ownership interests in 20 properties held in unconsolidated equity investments in the United States and Europe and one property held through the investment in CBRE Strategic Partners Asia. As of March 31, 2018 , the Company managed approximately $1,960,000 of commercial real estate assets, including approximately $1,408,000 of assets in Europe. During the three months ended March 31, 2018 , the Company acquired one property with 162,056 square feet for a purchase price of approximately $10,550 and placed one development property into service with 126,722 square feet. During the three months ended March 31, 2018 , the Company sold five properties and one warehouse from another asset aggregating 1,546,091 square feet for total gross proceeds of approximately $111,012 . Unless the context requires otherwise, all references to “Company," "Gramercy,” “we,” “our” and “us” mean Gramercy Property Trust and its subsidiaries, including the Operating Partnership and its consolidated subsidiaries.

Real Estate Investments

Real Estate Investments	3 Months Ended
	Mar. 31, 2018
Real Estate [Abstract]
Real Estate Investments	Real Estate Investments Investments in real estate properties consisted of the following: March 31, 2018 December 31, 2017 Square feet 1 Number of properties Investment Square feet 1 Number of properties Investment Operating properties 2 80,884,942 360 $ 5,811,702 82,146,063 363 $ 5,857,906 Land parcels 2 7,075 2 7,075 Less accumulated depreciation (368,815 ) (333,151 ) Total operating properties and land parcels $ 5,449,962 $ 5,531,830 Development properties 1,503,300 5 12,092 1,630,022 6 22,843 Total 82,388,242 367 $ 5,462,054 83,776,085 371 $ 5,554,673 1. Represents rentable square feet for operating properties and projected rentable square feet upon completion for development properties. 2. Includes development properties that have been completed as of the end of the period. Acquisitions: Real estate acquisition activity for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Number of operating properties 1 7 Rentable square feet of operating properties 162,056 2,257,311 Total purchase price of all acquisitions $ 10,550 $ 124,672 The total value of the properties acquired during the three months ended March 31, 2018 was comprised of $10,197 of real estate assets and $635 of intangible assets, including acquisition costs capitalized for the asset acquisitions. In addition to the operating property acquisition noted above, during the three months ended March 31, 2018 the Company also placed into service one development property which comprised 126,722 rentable square feet. Dispositions: Real estate disposition activity for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Number of properties 1 5 7 Rentable square feet 1,546,091 487,872 Gross proceeds $ 111,012 $ 51,683 Impairment of real estate investments related to asset dispositions during the period 2 $ — $ — Net gain on disposals $ 16,255 $ 17,377 1. During the three months ended March 31, 2018, the Company sold five properties and one warehouse from another asset. 2. Although there were no impairments recognized related to assets disposed during the three months ended March 31, 2018 and 2017 , as presented in the table, the Company recognized impairments on real estate investments of $12,771 during the three months ended March 31, 2017 related to properties held as of March 31, 2017, for which the Company determined there were nonrecoverable declines in value. Intangibles: Intangible assets and liabilities consisted of the following: Weighted average amortization period (years) March 31, 2018 December 31, 2017 Intangible assets: In-place leases, net of accumulated amortization of $214,664 and $194,836 9.3 $ 513,423 $ 545,782 Above-market leases, net of accumulated amortization of $26,854 and $25,229 6.8 43,979 46,713 Below-market ground rent, net of accumulated amortization of $421 and $408 17.5 5,811 6,064 Total intangible assets $ 563,213 $ 598,559 Intangible liabilities: Below-market leases, net of accumulated amortization of $30,685 and $28,516 39.5 $ 152,758 $ 159,652 Above-market ground rent, net of accumulated amortization of $516 and $462 32.0 6,786 6,839 Total intangible liabilities $ 159,544 $ 166,491 The following table provides the projected amortization expense of the intangible assets and liabilities for the next five years: April 1 to December 31, 2018 2019 2020 2021 2022 Depreciation and amortization expense $ 70,211 $ 84,228 $ 70,822 $ 59,528 $ 46,652 Rental revenue increase $ (1,571 ) $ (2,520 ) $ (4,004 ) $ (4,168 ) $ (6,260 ) The Company recorded $26,159 and $24,172 of amortization of in-place lease intangible assets as part of depreciation and amortization expense for the three months ended March 31, 2018 and 2017 , respectively. The Company recorded $494 and $621 of amortization of market lease intangible assets and liabilities as an increase to rental revenue for the three months ended March 31, 2018 and 2017 , respectively. Assets Held for Sale In the normal course of business, the Company identifies non-strategic assets for sale. The Company separately classifies properties held for sale in its Consolidated Financial Statements. As of March 31, 2018 and December 31, 2017, the Company had one asset classified as held for sale, which had a net asset value of $402 , all of which represented the value contained in real estate investments. Real estate investments to be disposed of are reported at the lower of carrying amount or estimated fair value, less costs to sell. Once an asset is classified as held for sale, depreciation and amortization expense is no longer recorded. Discontinued Operations The Company did not have significant discontinued operations for the three months ended March 31, 2018 . The Company’s discontinued operations for the three months ended March 31, 2017 were related to the assets assumed in the Company’s merger transaction in 2015 and simultaneously designated as held for sale.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Quarterly Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP, for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In management’s opinion, all adjustments (consisting of normal recurring accruals) considered necessary for fair presentation have been included. The 2018 operating results for the period presented are not necessarily indicative of the results that may be expected for the year ending December 31, 2018 . These Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and accompanying notes included in the Annual Report on Form 10-K for the year ended December 31, 2017 of the Company and the Operating Partnership. The Consolidated Balance Sheets at December 31, 2017 were derived from the audited Consolidated Financial Statements at that date. Reclassifications Certain prior year balances have been reclassified to conform with the current year presentation. During the fourth quarter of 2017, the Company adopted Accounting Standards Update, or ASU, No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, which requires restricted cash and cash equivalents to be included with cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the Consolidated Statements of Cash Flows. As a result of the adoption, net cash provided by operating activities changed by $235 , net cash used in investing activities changed by $(947) , and net cash provided by financing activities changed by $909 , for the three months ended March 31, 2017 . Principles of Consolidation The Consolidated Financial Statements include the Company’s accounts and those of the Company’s subsidiaries which are wholly-owned or controlled by the Company, or entities which are variable interest entities, or VIEs, in which the Company is the primary beneficiary. The primary beneficiary is the party that absorbs a majority of the VIE’s anticipated losses and/or a majority of the expected returns. The Company has evaluated its investments for potential classification as variable interests by evaluating the sufficiency of each entity’s equity investment at risk to absorb losses. Entities which the Company does not control and are considered VIEs, but where the Company is not the primary beneficiary, are accounted for under the equity method. All significant intercompany balances and transactions have been eliminated. The equity interests of other limited partners in the Company’s Operating Partnership are reflected as noncontrolling interests. See Note 11 for more information on the Company’s noncontrolling interests. Real Estate Investments Real Estate Acquisitions The Company evaluates its acquisitions of real estate, including equity interests in entities that predominantly hold real estate assets, to determine if the acquired assets meet the definition of a business and need to be accounted for as a business combination, or alternatively, should be accounted for as an asset acquisition. An integrated set of assets and activities acquired does not meet the definition of a business if either (i) substantially all the fair value of the gross assets acquired is concentrated in either a single identifiable asset or a group of similar identifiable assets, or (ii) the asset and activities acquired do not contain at least an input and a substantive process that together significantly contribute to the ability to create outputs. The Company expects that its acquisitions of real estate will continue to not meet the definition of a business. Acquisitions of real estate that do not meet the definition of a business, including sale-leaseback transactions that have newly-originated leases and real estate investments under construction, or build-to-suit investments, are recorded as asset acquisitions. The accounting for asset acquisitions is similar to the accounting for business combinations, except that the acquisition consideration, including acquisition costs, is allocated to the individual assets acquired and liabilities assumed on a relative fair value basis. Based on this allocation methodology, asset acquisitions do not result in the recognition of goodwill or a bargain purchase. The Company incurs internal transaction costs, which are direct, incremental internal costs related to acquisitions, that are recorded within general and administrative expense. Additionally, for build-to-suit investments in which the Company may engage a developer to construct a property or provide funds to a tenant to develop a property, the Company capitalizes the funds provided to the developer/tenant and real estate taxes, if applicable, during the construction period. To determine the fair value of assets acquired and liabilities assumed in an acquisition, which generally include land, building, improvements, and intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases at the acquisition date, the Company utilizes various estimates, processes and information to determine the as-if-vacant property value. Estimates of value are made using customary methods, including data from appraisals, comparable sales, and discounted cash flow analyses. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. The Company assesses the fair value of leases assumed at acquisition based upon estimated cash flow projections that utilize appropriate discount rates and available market information. Refer to the policy section "Intangible Assets and Liabilities" for more information on the Company’s accounting for intangibles. Depreciation is computed using the straight-line method over the shorter of the estimated useful life at acquisition of the capitalized item or 40 years for buildings, five to ten years for building equipment and fixtures, and the lesser of the useful life or the remaining lease term for tenant improvements and leasehold interests. Maintenance and repair expenditures are charged to expense as incurred. For transactions that qualify as business combinations, the Company recognizes the assets acquired and liabilities assumed at fair value, including the value of intangible assets and liabilities, and any excess or deficit of the consideration transferred relative to the fair value of the net assets acquired is recorded as goodwill or a bargain purchase gain, as appropriate. Acquisition costs of business combinations are expensed as incurred. Capital Improvements In leasing space, the Company may provide funding to the lessee through a tenant allowance. Certain improvements are capitalized when they are determined to increase the useful life of the building. During construction of qualifying projects, the Company capitalizes project management fees as permitted to be charged under the lease, if incremental and identifiable. In accounting for tenant allowances, the Company determines whether the allowance represents funding for the construction of leasehold improvements and evaluates the ownership of such improvements. If the Company is considered the owner of the leasehold improvements, the Company capitalizes the amount of the tenant allowance and depreciates it over the shorter of the useful life of the leasehold improvements or the lease term. If the tenant allowance represents a payment for a purpose other than funding leasehold improvements, or in the event the Company is not considered the owner of the improvements for accounting purposes, the allowance is considered to be a lease incentive and is recognized over the lease term as a reduction of rental revenue. Impairments and Disposals The Company reviews the recoverability of a property’s carrying value when circumstances indicate a possible impairment of the value of a property, such as an adverse change in future expected occupancy or a significant decrease in the market price of an asset. The review of recoverability is based on an estimate of the future undiscounted cash flows, excluding interest charges, expected to result from the property’s use and eventual disposition. These estimates consider factors such as changes in strategy resulting in an increased or decreased holding period, expected future operating income, market and other applicable trends and residual value, as well as the effects of leasing demand, competition and other factors. If management determines impairment exists due to the inability to recover the carrying value of a property, for properties to be held and used, an impairment loss is recorded to the extent that the carrying value exceeds the estimated fair value of the property and for assets held for sale, an impairment loss is recorded to the extent that the carrying value exceeds the fair value less estimated cost of disposal. These assessments are recorded as an impairment loss in the Consolidated Statements of Operations in the period the determination is made. The estimated fair value of the asset becomes its new cost basis. For a depreciable long-lived asset to be held and used, the new cost basis will be depreciated or amortized over the remaining useful life of that asset. The Company recognizes sales of real estate properties upon closing, at which time the Company transfers control of the assets to the purchaser. Payments received from purchasers prior to closing are recorded as deposits. Profit on real estate sold is based on the transaction price and is recognized using the full accrual method upon closing. Cash, Cash Equivalents, and Restricted Cash The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The Company's restricted cash primarily consists of reserves for certain capital improvements, leasing, interest and real estate tax and insurance payments as required by certain mortgage note obligations, as well as proceeds from property sales held by qualified intermediaries to be used for tax-deferred, like-kind exchanges under section 1031 of the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Consolidated Balance Sheets that sums to the total of the same such amounts shown in the Consolidated Statements of Cash Flows. As of March 31, 2018 2017 Cash and cash equivalents $ 41,964 $ 56,256 Restricted cash 15,041 13,101 Total cash, cash equivalents, and restricted cash $ 57,005 $ 69,357 Variable Interest Entities The Company had five consolidated VIEs and two unconsolidated VIEs as of March 31, 2018 and December 31, 2017 , which were determined based on the structure and control provisions of each entity. The Company’s five consolidated VIEs as of March 31, 2018 and December 31, 2017 included the Operating Partnership and four land parcels in Fort Mill, South Carolina acquired by an investment entity formed in December 2017, on which it will fund the development of four industrial facilities, or the Lakemont Development Investment. The Company has a 95.0% interest in the Lakemont Development Investment and will acquire the seller’s retained 5.0% interest when the properties are developed and leased. As of March 31, 2018 and December 31, 2017 , the Company’s carrying value of the Lakemont Development Investment was $4,674 and $4,584 , respectively. Unconsolidated VIEs The Company’s two unconsolidated VIEs as of March 31, 2018 and December 31, 2017 included its retained non-investment grade subordinate bonds, preferred shares and ordinary shares of two collateralized debt obligations, or CDOs, which are collectively herein referred to as the Retained CDO Bonds. Refer to the “Other Assets” section of this Note 2 and also to Note 7 for more information on the accounting and valuation of the Retained CDO Bonds. As of March 31, 2018 and December 31, 2017 , the Company’s carrying value of the Retained CDO Bonds was $5,800 and $5,527 , respectively. Tenant and Other Receivables Tenant and other receivables are derived from rental revenue, tenant reimbursements, and management fees. Rental revenue is recorded on a straight-line basis over the initial term of the lease. Since many leases provide for rental increases at specified intervals, straight-line basis accounting requires the Company to record a receivable, and include in revenues, unbilled rent receivables that will only be received if the tenant makes all rent payments required through the expiration of the initial term of the lease. Tenant and other receivables also include receivables related to tenant reimbursements for common area maintenance expenses and certain other recoverable expenses that are recognized as revenue in the period in which the related expenses are incurred. Tenant and other receivables are recorded net of the allowances for doubtful accounts, which as of March 31, 2018 and December 31, 2017 were $670 and $638 , respectively. The Company continually reviews receivables related to rent, tenant reimbursements, and management fees, including incentive fees, and determines collectability by taking into consideration the tenant or asset management clients’ payment history, the financial condition of the tenant or asset management client, business conditions in the industry in which the tenant or asset management client operates and economic conditions in the area in which the property or asset management client is located. In the event that the collectability of a receivable is in doubt, the Company increases the allowance for doubtful accounts or records a direct write-off of the receivable, as appropriate. Intangible Assets and Liabilities As discussed above in policy section, "Real Estate Acquisitions," the Company follows the acquisition method of accounting for its asset acquisitions and business combinations and thus allocates the purchase price of acquired properties to tangible and identifiable intangible assets acquired based on their respective fair values. Identifiable intangible assets include amounts allocated to acquired leases for above- and below-market lease rates and the value of in-place leases. Management also considers information obtained about each property as a result of its pre-acquisition due diligence. Above-market and below-market lease values for properties acquired are recorded based on the present value of the difference between the contractual amount to be paid pursuant to each in-place lease and management’s estimate of the fair market lease rate for each such in-place lease, measured over a period equal to the remaining non-cancelable term of the lease. The present value calculation utilizes a discount rate that reflects the risks associated with the leases acquired. The above-market and below-market lease values are amortized as a reduction of and increase to rental revenue, respectively, over the remaining non-cancelable terms of the respective leases. If a tenant terminates its lease prior to its contractual expiration and no future rental payments will be received, any unamortized balance of the market lease intangibles will be written off to rental revenue. The aggregate value of in-place leases represents the costs of leasing costs, other tenant related costs, and lost revenue that the Company did not have to incur by acquiring a property that is already occupied. Factors considered by management in its analysis of the in-place lease intangibles include an estimate of carrying costs during the expected lease-up period for each property taking into account current market conditions and costs to execute similar leases. In estimating carrying costs, management includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the anticipated lease-up period. Management also estimates costs to execute similar leases including leasing commissions and other related expenses. The value of in-place leases is amortized to depreciation and amortization expense over the remaining non-cancelable term of the respective leases. In no event does the amortization period for intangible assets exceed the remaining depreciable life of the building. If a tenant terminates its lease prior to its contractual expiration and no future rental payments will be received, any unamortized balance of the in-place lease intangible will be written off to depreciation and amortization expense. Above-market and below-market ground rent intangibles are recorded for properties acquired in which the Company is the lessee pursuant to a ground lease assumed at acquisition. The above-market and below-market ground rent intangibles are valued similarly to above-market and below-market leases, except that, because the Company is the lessee as opposed to the lessor, the above-market and below-market ground lease values are amortized as a reduction of and increase to rent expense, respectively, over the remaining non-cancelable terms of the respective leases. Refer to Note 3 for further information on the Company’s intangible assets and liabilities. Revenue Adoption of ASC Topic 606, "Revenue from Contracts with Customers" The Company adopted ASC Topic 606, which is described below in the section “Recently Issued Accounting Pronouncements,” on January 1, 2018 using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under the new guidance, while prior period amounts are not adjusted and continue to be reported in accordance with the historic accounting guidance in ASC Topic 605. As a result of adoption, the Company recorded an increase to its opening retained earnings balance of $663 as of January 1, 2018, which represents the cumulative impact of the new guidance and is related to the Company’s sale of real estate to Strategic Office Partners in 2016. There was no impact to revenues recorded for the three months ended March 31, 2018 as a result of adoption of the new revenue guidance. Revenue Recognition The Company recognizes revenue when control of the promised goods or services is transferred to a customer, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company’s primary sources of revenue include rental revenue, third-party management fees, operating expense reimbursements, and other income, which are disaggregated on the Consolidated Statements of Operations and are described in detail below. Real Estate Investments Rental revenue from leases on real estate investments is recognized on a straight-line basis over the term of the lease, regardless of when payments are contractually due. For leases on properties that are under construction at the time of acquisition, the Company begins recognition of rental revenue upon completion of construction of the leased asset and delivery of the leased asset to the tenant. The Company’s lease agreements with tenants also generally contain provisions that require tenants to reimburse the Company for real estate taxes, insurance costs, common area maintenance costs, and other property-related expenses. Under lease arrangements in which the Company is the primary obligor for these expenses, the Company recognizes such amounts as both revenues and operating expenses. Under lease arrangements in which the tenant pays these expenses directly, such amounts are not included in revenues or expenses. These reimbursement amounts are recognized in the period in which the related expenses are incurred. Management Fees The Company’s asset and property management agreements may contain provisions for fees related to dispositions, administration of the assets including fees related to accounting, valuation and legal services, and management of capital improvements or projects on the underlying assets. The Company recognizes revenue for fees pursuant to its management agreements in the period in which they are earned. Deferred revenue from management fees received prior to the date earned are included in other liabilities on the Consolidated Balance Sheets. For management fee agreements that include multiple performance obligations, the Company allocates revenue to each performance obligation based on its relative standalone selling price, which is primarily determined based on the prices charged to customers. Certain of the Company’s asset management contracts and agreements with its unconsolidated equity investments include provisions that allow it to earn additional fees, generally described as incentive fees or promoted interests, based on the achievement of a targeted valuation or the achievement of a certain internal rate of return on the managed assets held by third parties or the equity investment. The Company’s incentive fees are accounted for as variable consideration and revenue is recognized for them based on the Company’s estimate of the expected amount to which it will be entitled in exchange for its services. The Company recognizes promoted interest in the period in which it is determined to be appropriately earned pursuant to the terms of the specific agreement. The values of incentive fees and promoted interest fees are periodically evaluated by management. Other Income Other income primarily consists of income accretion on the Company’s Retained CDO Bonds, realized foreign currency exchange gains (losses), and interest income. Foreign Currency The Company's European management platform performs asset and property management services in Europe. The Company has unconsolidated equity investments in Europe and Asia and previously had two wholly-owned properties in Canada until their dispositions in March 2017. The Company also has borrowings outstanding in euros and British pounds sterling under the multicurrency portion of its revolving credit facility. Refer to Note 4 for more information on the Company’s foreign unconsolidated equity investments. Other Assets The Company includes prepaid expenses, capitalized software costs, contract intangible assets, deferred costs, loan investments, goodwill, derivative assets, and Retained CDO Bonds in other assets. Loan Investments The Company may originate loans related to specific real estate development projects. In October 2017, the Company entered into an agreement to provide a mezzanine construction loan facility with a maximum commitment of $250,000 to an industrial developer as borrower. As of March 31, 2018 and December 31, 2017, the carrying value of the Company’s loan investments was $22,437 and $22,154 , respectively, which represents the cost, net of accumulated amortization of loan costs. A s of March 31, 2018 , the loan investments had a weighted average interest rate of 10.47% . The Company evaluates its loan investments for possible credit losses each period. There were no loan reserves recorded during the three months ended March 31, 2018 and all of the Company’s loan investments were performing in accordance with the terms of the relevant investments as of March 31, 2018 . Goodwill The Company recognized goodwill of $3,802 related to the acquisition of Gramercy Europe Limited, which it adjusts each reporting period for the effect of foreign currency translation adjustments and tests for impairment on an annual basis, or more frequently if events or changes in circumstances indicate that the asset might be impaired. The carrying value of goodwill at March 31, 2018 and December 31, 2017 was $3,394 and $3,272 , respectively. The Company did no t record any impairment on its goodwill during the three months ended March 31, 2018 . Retained CDO Bonds The Retained CDO Bonds are non-investment grade subordinate bonds, preferred shares and ordinary shares of two CDOs. Management estimated the timing and amount of cash flows expected to be collected and recognized an investment in the Retained CDO Bonds equal to the net present value of these discounted cash flows. There is no guarantee that the Company will realize any proceeds from this investment, or what the timing will be for the expected remaining life of the Retained CDO Bonds. The Company considers these investments to be not of high credit quality and does not expect a full recovery of interest and principal. Therefore, the Company has suspended interest income accruals on these investments. The Company classifies the Retained CDO Bonds as available for sale. On a quarterly basis, the Company evaluates the Retained CDO Bonds to determine whether significant changes in estimated cash flows or unrealized losses on these investments, if any, reflect a decline in value which is other-than-temporary. If there is a decrease in estimated cash flows and the investment is in an unrealized loss position, the Company will record an other-than-temporary impairment, or OTTI, in the Consolidated Statements of Operations. To determine the component of the OTTI related to expected credit losses, the Company compares the amortized cost basis of the Retained CDO Bonds to the present value of the revised expected cash flows, discounted using the pre-impairment effective yield. Conversely, if the security is in an unrealized gain position and there is a decrease or significant increase in expected cash flows, the Company will prospectively adjust the yield using the effective yield method. Refer to Note 7 for further discussion regarding the fair value measurement of the Retained CDO Bonds. For the three months ended March 31, 2018 and 2017, the Company recognized OTTI on its Retained CDO Bonds of $0 and $4,890 , respectively. A summary of the Company’s Retained CDO Bonds as of March 31, 2018 is as follows: Number of Securities Face Value Amortized Cost Gross Unrealized Gain Other-Than-Temporary Impairment Fair Value Weighted Average Expected Life (years) 6 $ 329,597 $ 5,431 $ 369 $ — $ 5,800 1.1 Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash investments, debt investments and accounts receivable. The Company places its cash investments in excess of insured amounts with high quality financial institutions. Concentrations of credit risk also arise when a number of the Company’s tenants or asset management clients are engaged in similar business activities or are subject to similar economic risks or conditions that could cause their inability to meet contractual obligations to the Company. The Company regularly monitors its portfolio to assess potential concentrations of credit risk. Management believes the current credit risk portfolio is reasonably well diversified. During the three months ended March 31, 2018 and 2017, there were no tenants that accounted for 10.0% or more of the Company's rental revenue. Additionally, for the three months ended March 31, 2018 , there were three states, Illinois , Texas , and Florida , that each accounted for 10.0% or more of the Company’s rental revenue. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Recently Issued Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09 (Topic 606), Revenue from Contracts with Customers, which is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to customers in an amount reflecting the consideration it expects to receive in exchange for those goods or services. In April 2016 and February 2017, the FASB issued ASU 2016-10 and ASU 2017-05, respectively, which further clarified the new revenue recognition guidance under ASC Topic 606. The Company adopted the guidance on January 1, 2018 using the modified retrospective method, which did not have a material impact on its Consolidated Financial Statements. Refer to the “Revenue” section above for further detail. In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. The guidance requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to record changes in instruments specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. The update is effective for fiscal years beginning after December 15, 2017, and for interim periods therein. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. Refer to Note 8 for more information. I n February 2016, the FASB issued ASU 2016-02, Leases, which 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 update will be effective beginning in the first quarter of 2019 and early adoption is permitted. The new standard requires a modified retrospective transition approach for all leases existing at, or entered into after, the date of initial application, with an option to use certain transition relief. The Company’s accounting for leases in which it is a lessor, which represents most of its leasing arrangements, will be largely unchanged under ASU 2016-02; however, the Company is a lessee in several operating and ground leases and the accounting for these arrangements is more significantly impacted by the new standard. Pursuant to the new guidance, lessees are required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. The Company is continuing to evaluate the impact of adopting the new leases standard on its Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows Classification of Certain Cash Receipts and Cash Payments, which serves to reduce the diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The update is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation: Scope of Modification Accounting. The amendment provides guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting. The guidance is effective for annual and interim periods beginning after December 15, 2017, with early adoption permitted under certain circumstances. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. The transition guidance provides companies with the option of early adopting the new standard using a modified retrospective transition method in any interim period after issuance of the update, or alternatively requires adoption for fiscal years beginning after December 15, 2018. In the first quarter of 2018, the Company early adopted this standard and the adoption did not have a material impact on its Consolidated Financial Statements.

Unconsolidated Equity Investmen

Unconsolidated Equity Investments	3 Months Ended
	Mar. 31, 2018
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Unconsolidated Equity Investments	Unconsolidated Equity Investments The Company has investments in a variety of ventures. The Company will co-invest in entities that own multiple properties with various investors or with one partner. The Company may manage the ventures and earn fees, such as asset and property management fees, incentive fees, and promoted interest for its services, or one of the other partners will manage the ventures for similar such fees. Depending on the structure of the venture, the Company’s voting interest may be different than its economic interest. The Company accounts for substantially all of its unconsolidated equity investments under the equity method of accounting because it exercises significant influence, but does not unilaterally control the entities, and is not considered to be the primary beneficiary. In unconsolidated equity investments, the rights of the other investors are protective and participating. Unless the Company is determined to be the primary beneficiary, these rights preclude it from consolidating the investments. The investments are recorded initially at cost as unconsolidated equity investments, as applicable, and subsequently are adjusted for equity interest in net income and contributions and distributions. The amount of the investments on the Consolidated Balance Sheets is evaluated for impairment at each reporting period. None of the unconsolidated equity investment debt is recourse to the Company. Transactions with unconsolidated equity method entities are eliminated to the extent of the Company’s ownership in each such entity. Accordingly, the Company’s share of net income of these equity method entities is included in consolidated net income. As of March 31, 2018 and December 31, 2017 , the Company owned properties through unconsolidated equity investments and had investment interests in these unconsolidated entities as follows: As of March 31, 2018 As of December 31, 2017 Investment Ownership % Voting Interest % Partner Investment in Unconsolidated Equity Investment 1 No. of Properties Investment in Unconsolidated Equity Investment 1 No. of Properties Strategic Office Partners 25.0 % 25.0 % TPG Real Estate $ 28,792 13 $ 28,243 13 E-Commerce JV 51.0 % 50.0 % Ample Glow Investments 43,502 2 17,798 — Goodman UK JV 80.0 % 50.0 % Goodman Group 15,980 1 15,768 1 Gramercy European Property Fund III 19.9 % 50.0 % Various 5,363 2 2,949 — Other 2 5.1% - 50.0% 5.1% - 50.0% Various 5,476 3 5,456 3 Total $ 99,113 21 $ 70,214 17 1. The amounts presented include a basis difference of $2,011 and $1,943 , net of accumulated amortization, for the Goodman UK JV as of March 31, 2018 and December 31, 2017 , respectively. The amounts presented include a basis difference of $(3,916) , net of accumulated amortization, for the E-Commerce JV as of March 31, 2018 . 2. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV. The following is a summary of the Company’s unconsolidated equity investments for the three months ended March 31, 2018 : Unconsolidated Equity Investments Balance at January 1, 2018 $ 70,214 Contributions to unconsolidated equity investments 28,731 Equity in net loss of unconsolidated equity investments, including adjustments for basis differences (926 ) Other comprehensive income of unconsolidated equity investments 431 Cumulative effect of accounting change 663 Balance at March 31, 2018 $ 99,113 Strategic Office Partners In August 2016, the Company partnered with TPG Real Estate, or TPG, to form Strategic Office Partners, an unconsolidated equity investment created for the purpose of acquiring, owning, operating, leasing and selling single-tenant office properties located in high-growth metropolitan areas in the United States. The Company provides asset and property management, accounting, construction, and leasing services to Strategic Office Partners, for which it earns management fees and is entitled to a promoted interest. TPG and the Company have committed an aggregate $400,000 to Strategic Office Partners, including $100,000 from the Company. During the three months ended March 31, 2018 , the Company did not make any contributions to or receive any distributions from Strategic Office Partners. E-Commerce JV In November 2017, the Company formed a joint venture with an investment partner, which will acquire, own and manage Class A distribution centers leased to leading e-commerce tenants on long-term leases across the United States, or the E-Commerce JV. The Company has joint control over the E-Commerce JV, which is shared equally with its investment partner. The Company provides asset and property management and accounting services to the E-Commerce JV, for which it earns management fees. The Company has committed capital to fund its initial acquisition of six properties, as well as the acquisition of additional properties in the future, subject to the partners' approval. The Company's pro rata funding commitment for the initial six properties is estimated at approximately $110,000 , of which approximately $80,000 will be funded in OP Units issued to the seller of the property and approximately $30,000 will be funded in cash. During the three months ended March 31, 2018 , the E-Commerce JV acquired two properties. During the three months ended March 31, 2018 , the Company contributed $1,130 in cash and OP Units valued at approximately $25,141 to the E-Commerce JV. Goodman UK JV The Goodman UK JV invests in industrial properties in the United Kingdom. During the three months ended March 31, 2018 and 2017, the Company received no distributions from the Goodman UK JV. European Investment Funds Gramercy European Property Fund III In October 2017, the Company formed a new European investment fund with several other equity investment partners, or the Gramercy European Property Fund III, which has total initial capital commitments of $323,359 ( €262,622 ) from all investors, of which the Company’s initial capital commitment is $64,257 ( €52,187 ), representing an interest of approximately 19.9% . The Company provides asset and property management and accounting services to the Gramercy European Property Fund III, for which it is entitled to management fees and a promoted interest. During the three months ended March 31, 2018 , the Gramercy European Property Fund III acquired two properties. During the three months ended March 31, 2018 , the Company contributed $2,460 ( €1,977 ) to the Gramercy European Property Fund III. Gramercy European Property Fund In July 2017, the Gramercy European Property Fund sold 100.0% of its assets to a third party, and, concurrently, the Company sold its 5.1% direct interest in the Goodman Europe JV to the same entity that acquired the Gramercy European Property Fund's assets. In connection with the sale transactions, the Company's management contract arrangement with the Gramercy European Property Fund was terminated; however, the Company continues to manage the assets for the new owner through June 2018. The following are the balance sheets for the Company’s unconsolidated equity investments at March 31, 2018 : Strategic Office Partners E-Commerce JV Goodman UK JV Gramercy European Property Fund III Other 1 Assets: Real estate assets, net 2 $ 264,099 $ 149,895 $ 19,150 $ 62,284 $ 108,993 Other assets 80,897 48,894 1,751 5,428 18,421 Total assets $ 344,996 $ 198,789 $ 20,901 $ 67,712 $ 127,414 Liabilities and members' equity: Mortgage notes payable $ 213,699 $ 108,473 $ — $ 35,873 $ 38,341 Other liabilities 16,698 5,018 732 4,850 19,043 Total liabilities 230,397 113,491 732 40,723 57,384 Company's equity 28,792 43,502 15,980 5,363 5,476 Other members' equity 85,807 41,796 4,189 21,626 64,554 Liabilities and members' equity $ 344,996 $ 198,789 $ 20,901 $ 67,712 $ 127,414 1. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV. 2. Includes basis adjustments recorded by the Company to adjust the unconsolidated equity investments to fair value. The following are the balance sheets for the Company’s unconsolidated equity investments at December 31, 2017 : Strategic Office Partners E-Commerce JV Goodman UK JV Other 1 Assets: Real estate assets, net 2 $ 265,014 $ — $ 18,633 $ 107,949 Other assets 78,243 35,727 1,473 34,022 Total assets $ 343,257 $ 35,727 $ 20,106 $ 141,971 Liabilities and members' equity: Mortgage notes payable $ 213,205 $ — $ — $ 38,662 Other liabilities 15,002 830 203 19,329 Total liabilities 228,207 830 203 57,991 Company's equity 28,243 17,798 15,768 8,405 Other members' equity 86,807 17,099 4,135 75,575 Liabilities and members' equity $ 343,257 $ 35,727 $ 20,106 $ 141,971 1. Includes CBRE Strategic Partners Asia, the Philips JV, the Morristown JV, and the Gramercy European Property Fund III. 2. Includes basis adjustments recorded by the Company to adjust the unconsolidated equity investments to fair value. Certain real estate assets in the Company’s unconsolidated equity investments are subject to mortgage notes. The following is a summary of the secured financing arrangements within the Company’s unconsolidated equity investments as of March 31, 2018 : Outstanding Balance 2 Property Unconsolidated Equity Investment Economic Ownership Interest Rate 1 Maturity Date March 31, 2018 December 31, 2017 Strategic Office Partners Facility 1 3 Strategic Office Partners 25.0% 4.70% 10/7/2019 $ 169,380 $ 169,380 Strategic Office Partners Facility 2 4 Strategic Office Partners 25.0% 9.21% 10/8/2020 39,540 39,540 E-Commerce JV Facility 4 E-Commerce JV 51.0% 3.38% 2/10/2023 109,846 — Gramercy European Property Fund III Facility 4 Gramercy European Property Fund III 19.9% 1.57% 3/12/2023 36,084 — Henderson, NV Strategic Office Partners 25.0% 4.75% 8/6/2025 8,593 8,636 Somerset, NJ Philips JV 25.0% 6.90% 9/11/2035 38,341 38,662 Total mortgage notes payable $ 401,784 $ 256,218 Net deferred financing costs and net debt discount (5,398 ) (4,351 ) Total mortgage notes payable, net $ 396,386 $ 251,867 1. Represents the current effective rate as of March 31, 2018 , including the swapped interest rate for mortgage notes that have interest rate swaps. The current interest rate is not adjusted to include the amortization of fair market value premiums or discounts. 2. Mortgage notes are presented at 100.0% of the amount held by the unconsolidated equity investment. 3. As of March 31, 2018 , there were ten properties under this mortgage note. 4. As of March 31, 2018 , there were two properties under each of these mortgage notes. The following are the statements of operations for the Company’s unconsolidated equity investments for the three months ended March 31, 2018 : Strategic Office Partners E-Commerce JV Goodman UK JV Gramercy European Property Fund III Other 1 Revenues $ 11,143 $ 2,165 $ — $ 482 $ 1,994 Operating expenses 4,151 583 260 682 106 Interest expense 3,113 669 — 97 666 Depreciation and amortization 4,823 862 206 209 333 Total expenses 12,087 2,114 466 988 1,105 Net income (loss) from operations (944 ) 51 (466 ) (506 ) 889 Gain on derivatives 492 — — — — Loss on extinguishment of debt — (1,200 ) — — Net income (loss) $ (452 ) $ (1,149 ) $ (466 ) $ (506 ) $ 889 Company's share in net income (loss) $ 26 $ (520 ) $ (373 ) $ (93 ) $ 20 Adjustments for REIT basis — 18 (4 ) — — Company's equity in net income (loss) within continuing operations $ 26 $ (502 ) $ (377 ) $ (93 ) $ 20 1. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV. The following are the statements of operations for the Company’s unconsolidated equity investments for the three months ended March 31, 2017 : Gramercy European Property Fund 1 Goodman Europe JV Gramercy European Property Fund 2 Total Strategic Office Partners Goodman UK JV Other 3 Revenues $ 4,955 $ 10,118 $ 15,073 $ 5,526 $ 295 $ (1,331 ) Operating expenses 922 2,951 3,873 1,474 302 576 Interest expense 672 1,474 2,146 1,510 — 641 Depreciation and amortization 2,021 4,473 6,494 2,503 375 333 Total expenses 3,615 8,898 12,513 5,487 677 1,550 Net income (loss) from operations 1,340 1,220 2,560 39 (382 ) (2,881 ) Gain (loss) on derivatives — 1,221 1,221 (349 ) — — Provision for taxes (17 ) 146 129 — (8 ) — Net income (loss) $ 1,323 $ 2,587 $ 3,910 $ (310 ) $ (390 ) $ (2,881 ) Company’s share in net income (loss) $ 67 $ 446 $ 513 $ (15 ) $ (312 ) $ (155 ) Adjustments for REIT basis (36 ) — (36 ) — (89 ) — Company’s equity in net income (loss) within continuing operations $ 31 $ 446 $ 477 $ (15 ) $ (401 ) $ (155 ) 1. As of and for the three months ended March 31, 2017 , the Company had a 5.1% direct interest in the Goodman Europe JV as well as an indirect interest in the remaining 94.9% interest that was held through the Company’s 14.2% interest in the Gramercy European Property Fund. For the three months ended March 31, 2017 , the Company’s equity in net income (loss) from the entities is based on these ownership interest percentages during the period. 2. Excludes the results of the Gramercy European Property Fund’s 94.9% interest in the Goodman Europe JV, as the Goodman Europe JV is separately presented. 3. Includes CBRE Strategic Partners Asia, the Philips JV, the Morristown JV, and European Fund Carry Co.

Debt Obligations

Debt Obligations	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Debt Obligations	Debt Obligations Secured Debt Mortgage Notes Certain real estate assets are subject to mortgage notes. During the three months ended March 31, 2018 , the Company did not assume or pay off any mortgages notes. During the year ended December 31, 2017 , the Company assumed $181,107 of non-recourse mortgages in connection with seven real estate acquisitions. During the three months ended March 31, 2017, the Company refinanced the debt on two properties encumbered by a mortgage note, subsequently transferred the mortgage on these two properties to the buyer of the properties, and, as a result, recorded a net loss on the early extinguishment of debt of $208 . The Company’s mortgage notes include a series of financial and other covenants with which the Company must comply in order to borrow under them. The Company was in compliance with the covenants under the mortgage note facilities as of March 31, 2018 . The following is a summary of the Company’s secured financing arrangements as of March 31, 2018 and December 31, 2017 : Property Interest Rate 1 Maturity Date Outstanding Balance March 31, 2018 December 31, 2017 Greenwood, IN 3.59% 6/15/2018 $ 7,211 $ 7,257 Greenfield, IN 3.63% 6/15/2018 5,828 5,865 Logistics Portfolio - Pool 3 2 3.96% 8/1/2018 43,302 43,302 Philadelphia, PA 4.99% 1/1/2019 11,842 11,943 Bridgeview, IL 3.90% 5/1/2019 5,792 5,838 Spartanburg, SC 3.20% 6/1/2019 530 632 Charleston, SC 3.11% 8/1/2019 320 457 Lawrence, IN 5.02% 1/1/2020 19,896 20,061 Charlotte, NC 3.28% 1/1/2020 1,363 1,538 Hawthorne, CA 3.52% 8/1/2020 17,042 17,207 Charleston, SC 3.32% 10/1/2020 696 758 Charleston, SC 2.97% 10/1/2020 684 746 Charleston, SC 3.37% 10/1/2020 684 746 Charlotte, NC 3.38% 10/1/2020 594 647 Des Plaines, IL 5.54% 10/31/2020 2,365 2,385 Waco, TX 4.75% 12/19/2020 14,815 14,890 Deerfield, IL 3.71% 1/1/2021 10,355 10,447 Winston-Salem, NC 3.41% 6/1/2021 3,135 3,354 Winston-Salem, NC 3.42% 7/1/2021 1,043 1,114 Logistics Portfolio - Pool 1 2 4.27% 1/1/2022 37,856 38,107 CCC Portfolio 2 4.24% 10/6/2022 22,691 22,814 Logistics Portfolio - Pool 4 2 4.36% 12/5/2022 79,500 79,500 Romeoville, IL 3.80% 4/6/2023 24,835 24,951 Romeoville, IL 3 9.37% 4/6/2023 6,613 6,623 KIK USA Portfolio 2 4.31% 7/6/2023 7,077 7,154 Yuma, AZ 5.27% 12/6/2023 11,804 11,858 Allentown, PA 5.16% 1/6/2024 22,586 22,690 Spartanburg, SC 3.72% 2/1/2024 5,447 5,635 Natick, MA 5.21% 3/1/2024 31,121 31,224 Natick, MA 3 10.38% 3/1/2024 3,458 3,469 Maple Grove, MN 3.88% 5/6/2024 16,291 16,380 Curtis Bay, MD 4.31% 7/1/2024 13,500 13,500 Rialto, CA 3.91% 8/1/2024 54,543 54,741 Houston, TX 3.68% 9/1/2024 26,000 26,000 Durham, NC 4.02% 9/6/2024 3,614 3,631 Charleston, SC 3.80% 2/1/2025 5,831 6,001 Hackettstown, NJ 5.49% 3/6/2026 9,420 9,455 Hutchins, TX 5.41% 6/1/2029 21,269 21,578 Total mortgage notes payable $ 550,953 $ 554,498 Net deferred financing costs and net debt premium 8,520 9,023 Total mortgage notes payable, net $ 559,473 $ 563,521 1. Represents the interest rate as of March 31, 2018 that was recorded for financial reporting purposes, which reflects the effect of interest rate swaps and amortization of financing costs and fair market value premiums or discounts. 2. As of March 31, 2018, there were two properties under the Logistics Portfolio - Pool 3 mortgage, three properties under the Logistics Portfolio - Pool 1 mortgage, five properties under the CCC Portfolio mortgage, six properties under the Logistics Portfolio - Pool 4 mortgage, and three properties under the KIK USA Portfolio mortgage. 3. Mortgage notes represent mezzanine financing at the properties. Unsecured Debt 2015 Credit Facility and Term Loans In December 2015, the Company entered into an agreement, or the Credit Agreement, for a new $1,900,000 credit facility, or the 2015 Credit Facility, consisting of an $850,000 senior unsecured revolving credit facility, or the 2015 Revolving Credit Facility, and $1,050,000 term loan facility with JPMorgan Securities LLC and Merrill Lynch, Pierce, Fenner and Smith Incorporated. The 2015 Revolving Credit Facility consists of a $750,000 U.S. dollar revolving credit facility and a $100,000 multicurrency revolving credit facility. The 2015 Revolving Credit Facility matures in January 2020, but may be extended for two additional six-month periods upon the payment of applicable fees and satisfaction of certain customary conditions. The term loan facility, or the 2015 Term Loan, consists of a $300,000 term loan facility that matures in January 2019 with one 12-month extension option, or the 3-Year Term Loan, and a $750,000 term loan facility that matures in January 2021, or the 5-Year Term Loan. In December 2015, the Company also entered into a new $175,000 7 -year unsecured term loan with Capital One, N.A, or the 7-Year Term Loan, which matures in January 2023 . In October 2017, the Company modified the 7-Year Term Loan by increasing the loan amount to $400,000 and reducing the interest rate to the terms described below. Outstanding borrowings under the 2015 Revolving Credit Facility incur interest at a floating rate based upon, at the Company's option, either (i) adjusted LIBOR plus an applicable margin ranging from 0.88% to 1.55% , depending on the Company's credit ratings, or (ii) the alternate base rate plus an applicable margin ranging from 0.00% to 0.55% , depending on the Company's credit ratings. The Company is also required to pay quarterly in arrears a 0.13% to 0.30% facility fee, depending on its credit ratings, on the total commitments under the 2015 Revolving Credit Facility. Outstanding borrowings under the 2015 Term Loan and the 7-Year Term Loan incur interest at a floating rate based upon, at the Company's option, either (i) adjusted LIBOR plus an applicable margin ranging from 0.90% to 1.75% , depending on the Company's credit ratings, or (ii) the alternate base rate plus an applicable margin ranging from 0.00% to 0.75% , depending on the Company's credit ratings. The alternate base rate for the 2015 Revolving Credit Facility and the 7-Year Term Loan is the greater of (x) the prime rate announced by JPMorgan Chase Bank, N.A. or Capital One, respectively, (y) 0.50% above the Federal Funds Effective Rate, and (z) the adjusted LIBOR for a one-month interest period plus 1.00% . The Company’s unsecured borrowing facilities include a series of financial and other covenants with which the Company must comply in order to borrow under the facilities. The Company was in compliance with the covenants under the facilities as of March 31, 2018 . Refer to the table at the end of this Note 5 for specific terms and the Company’s outstanding borrowings under the facilities. Senior Unsecured Notes During 2015 and 2016, the Company issued and sold an aggregate $500,000 principal amount of senior unsecured notes payable in private placements, which have maturities ranging from 2022 through 2026 and bear interest semiannually at rates ranging from 3.89% to 4.97% . Refer to the table later in Note 5 for specific terms of the Company's Senior Unsecured Notes. Exchangeable Senior Notes In September 2017, the Company's $115,000 of 3.75% Exchangeable Senior Notes were exchanged for 5,258,420 of the Company's common shares. The terms of the Company’s unsecured debt obligations and outstanding balances as of March 31, 2018 and December 31, 2017 are set forth in the table below: Stated Interest Rate Effective Interest Rate 1 Maturity Date Outstanding Balance March 31, 2018 December 31, 2017 2015 Revolving Credit Facility - USD tranche 2.89 % 2.89 % 1/8/2020 $ 275,000 $ 345,000 2015 Revolving Credit Facility - Multicurrency tranche 1.32 % 1.32 % 1/8/2020 17,543 12,162 3-Year Term Loan 2.91 % 2.33 % 1/8/2019 300,000 300,000 5-Year Term Loan 2.91 % 2.70 % 1/8/2021 750,000 750,000 7-Year Term Loan 2.76 % 3.00 % 1/9/2023 400,000 400,000 2015 Senior Unsecured Notes 4.97 % 5.07 % 12/17/2024 150,000 150,000 2016 Senior Unsecured Notes 3.89 % 4.00 % 12/15/2022 150,000 150,000 2016 Senior Unsecured Notes 4.26 % 4.38 % 12/15/2025 100,000 100,000 2016 Senior Unsecured Notes 4.32 % 4.43 % 12/15/2026 100,000 100,000 Total unsecured debt 2,242,543 2,307,162 Net deferred financing costs and net debt discount (4,872 ) (5,063 ) Total unsecured debt, net $ 2,237,671 $ 2,302,099 1. Represents the rate at which interest expense is recorded for financial reporting purposes as of March 31, 2018 , which reflects the effect of interest rate swaps and amortization of financing costs and fair market value premiums or discounts. Combined aggregate principal maturities of the Company’s unsecured debt obligations and non-recourse mortgages, in addition to associated interest payments, as of March 31, 2018 are as follows: April 1 to December 31, 2018 2019 2020 2021 2022 Thereafter Above market interest Total 2015 Revolving Credit Facility $ — $ — $ 292,543 $ — $ — $ — $ — $ 292,543 Term Loans — 300,000 — 750,000 — 400,000 — 1,450,000 Mortgage Notes Payable 1 66,599 30,450 62,834 19,256 141,929 229,885 — 550,953 Senior Unsecured Notes — — — — 150,000 350,000 — 500,000 Interest Payments 2 82,144 97,025 87,135 57,199 53,364 64,772 3,648 445,287 Total $ 148,743 $ 427,475 $ 442,512 $ 826,455 $ 345,293 $ 1,044,657 $ 3,648 $ 3,238,783 1. Mortgage note payments reflect accelerated repayment dates, when applicable, pursuant to the related agreement. 2. Interest payments do not reflect the effect of interest rate swaps.

Transactions with Trustee Relat

Transactions with Trustee Related Entities and Related Parties	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Transactions with Trustee Related Entities and Related Parties	Transactions with Trustee Related Entities and Related Parties The Company’s CEO, Gordon F. DuGan, was on the board of directors of the Gramercy European Property Fund prior to its sale in July 2017 and committed and fully funded approximately $1,388 ( €1,250 ) in capital to the Gramercy European Property Fund. The two Managing Directors of Gramercy Europe Limited collectively committed and fully funded approximately $1,388 ( €1,250 ) in capital to the Gramercy European Property Fund prior to the sale of its assets in July 2017.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements ASC 820-10, “Fair Value Measurements and Disclosures,” provides guidance on the fair value measurement of a financial asset or liability. Inputs used to develop fair value measurements are classified into one of three categories: Level I, defined as observable inputs such as quoted prices in active markets for identical assets or liabilities; Level II, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level III, defined as unobservable inputs for which there is little or no market or pricing data, thus requiring management to use its judgment and develop its own assumptions. The following table presents the carrying value in the financial statements and approximate fair value of assets and liabilities measured on a recurring and non-recurring basis at March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Financial assets: Interest rate swaps $ 41,888 $ 41,888 $ 19,668 $ 19,668 Retained CDO Bonds 5,800 5,800 5,527 5,527 Real estate investments 1 — — 87,996 87,996 Investment in CBRE Strategic Partners Asia 2,869 2,869 2,820 2,820 Loan investments 2 22,437 20,990 22,154 21,362 Financial liabilities: Interest rate swaps $ 13 $ 13 $ 173 $ 173 Long-term debt: 2015 Revolving Credit Facility 2 292,543 292,492 357,162 357,369 3-Year Term Loan 2 300,000 300,090 300,000 300,091 5-Year Term Loan 2 750,000 750,653 750,000 750,678 7-Year Term Loan 2 398,241 400,020 398,152 400,010 Mortgage notes payable 2 559,473 565,329 563,521 573,826 Senior Unsecured Notes 2 496,887 502,349 496,785 513,229 1. Amount represents seven real estate investments that were impaired by the Company and held as of December 31, 2017 . 2. Long-term debt instruments are classified as Level III due to the significance of unobservable inputs which are based upon management assumptions. The following methods and assumptions were used to estimate the fair value of each class of assets and liabilities for which it is practicable to estimate the value: Cash and cash equivalents, marketable securities, accrued interest, and accounts payable: These balances in the Consolidated Financial Statements reasonably approximate their fair values due to the items’ short maturities. Loan investments: Loan investments are presented in other assets on the Consolidated Financial Statements at amortized cost and not fair value. The fair value of each investment is estimated by a discounted cash flow model, using discount rates that best reflect current market rates for financings with similar characteristics and credit quality. Mortgage notes payable, unsecured term loans, unsecured revolving credit facilities and senior unsecured notes: These instruments are presented in the Consolidated Financial Statements at amortized cost and not at fair value. The fair value of each instrument is estimated by a discounted cash flows model, using discount rates that best reflect current market rates for financings with similar characteristics and credit quality. Retained CDO Bonds, investment in CBRE Strategic Partners Asia, real estate investments, and interest rate swaps: Refer to section below, “Valuation of Level III Instruments,” for valuation methods and assumptions used for these Level III assets and liabilities measured at fair value in the Consolidated Financial Statements. The following discussion of fair value was determined by the Company using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair value. Accordingly, fair values are not necessarily indicative of the amounts the Company could realize on disposition of the assets or liabilities. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. Assets and liabilities measured at fair value on a recurring and non-recurring basis are categorized as follows: At March 31, 2018 Total Level I Level II Level III Financial Assets: Retained CDO Bonds $ 5,800 $ — $ — $ 5,800 Investment in CBRE Strategic Partners Asia 2,869 — — 2,869 Interest rate swaps 41,888 — — 41,888 $ 50,557 $ — $ — $ 50,557 Financial Liabilities: Interest rate swaps $ (13 ) $ — $ — $ (13 ) $ (13 ) $ — $ — $ (13 ) At December 31, 2017 Total Level I Level II Level III Financial Assets: Retained CDO Bonds $ 5,527 $ — $ — $ 5,527 Real estate investments 87,996 — — 87,996 Investment in CBRE Strategic Partners Asia 2,820 — — 2,820 Interest rate swaps 19,668 — — 19,668 $ 116,011 $ — $ — $ 116,011 Financial Liabilities: Interest rate swaps $ (173 ) $ — $ — $ (173 ) $ (173 ) $ — $ — $ (173 ) Valuation of Level III Instruments Retained CDO Bonds: Retained CDO Bonds are valued on a recurring basis using an internally developed discounted cash flow models, which require significant assumptions and judgment. The models are most sensitive to the unobservable inputs such as the amount of the recoveries of the underlying securities. Investment in CBRE Strategic Partners Asia: The Company's investment in CBRE Strategic Partners Asia is based on the Level III valuation inputs applied by the investment manager of CBRE Strategic Partners Asia, utilizing a mix of different approaches for valuing the underlying real estate related investments within the investment company. The valuations are most sensitive to the unobservable inputs of discount rates, as well as capitalization rates an expected future cash flows. Real estate investments: Real estate investments impaired during a period are reported at estimated fair value and real estate investments impaired during a period that are classified as held for sale as of the end of the period are reported at estimated fair value less costs to sell. The fair value of real estate investments and their related lease intangibles is determined using third-party valuation support, including purchase-sale contracts and other available market information. Key assumptions in the valuations, to which the fair value determinations are most sensitive, include discount and capitalization rates as well as expected future cash flows. Interest rate swaps: The Company's derivative instruments as of March 31, 2018 and December 31, 2017 consist of interest rate swaps, which are valued with the assistance of a third-party derivative specialist using a discounted cash flow model, that requires a combination of observable market-based inputs, such as interest rate curves, and unobservable inputs which require significant judgment such as the credit valuation adjustments due to the risk of nonperformance by both the Company and its counterparties. The most significant unobservable input in the fair valuation of interest rate swaps is the credit valuation adjustment as it requires significant management judgment regarding changes in the credit risk of the Company or its counterparties, however the primary driver of the fair value of the interest rate swaps is the forward interest rate curve. Fair Value on a Recurring Basis Quantitative information regarding the valuation techniques and the range of significant unobservable Level III inputs used to determine fair value measurements on a recurring basis as of March 31, 2018 are as follows: Financial Asset (Liability) Fair Value Valuation Technique Unobservable Inputs Range Non-investment grade, subordinate CDO bonds $ 5,800 Discounted cash flows Discount rate 19.0% Investment in CBRE Strategic Partners Asia 2,869 Discounted cash flows Discount rate 20.0% Interest rate swaps 1 41,875 Hypothetical derivative method Credit borrowing spread 110 to 190 basis points 1. Fair value includes interest rate swap liabilities with an aggregate value of $(13) . The following rollforward table reconciles the beginning and ending balances of financial assets (liabilities) measured at fair value on a recurring basis using Level III inputs as of March 31, 2018 : Retained CDO Bonds Investment in CBRE Strategic Partners Asia Interest Rate Swaps Total Financial Assets (Liabilities) - Level III Balance at January 1, 2018 $ 5,527 $ 2,820 $ 19,495 $ 27,842 Amortization of discounts or premiums 321 — 330 651 Adjustments to fair value: Unrealized gain on derivatives — — 22,050 22,050 Unrealized loss in other comprehensive income from fair value adjustment (48 ) — — (48 ) Total gain on fair value adjustments — 49 — 49 Balance at March 31, 2018 $ 5,800 $ 2,869 $ 41,875 $ 50,544 Fair Value on a Non-Recurring Basis The Company measures its real estate investments impaired during a period, including both assets classified as held for sale and assets held for investment, on a non-recurring basis, and records impairment on these assets as a result of a change in intent to hold the real estate investments. Real estate investments impaired during a period are reported at estimated fair value and real estate investments impaired during a period that are classified as held for sale as of the end of the period are reported at estimated fair value less costs to sell. There were no assets measured on a non-recurring basis as of March 31, 2018 . There were seven assets measured on a non-recurring basis as of December 31, 2017 , which were all classified as held for investment and recorded at $87,996 as of December 31, 2017 .

Derivatives and Non-Derivative

Derivatives and Non-Derivative Hedging Instruments	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Non-Derivative Hedging Instruments	Derivatives and Non-Derivative Hedging Instruments In the normal course of business, the Company is exposed to the effect of interest rate changes and foreign exchange rate changes. The Company limits these risks by following established risk management policies and procedures including the use of derivatives and net investment hedges. The Company uses a variety of derivative instruments to manage, or hedge, interest rate risk. The Company enters into hedging and derivative instruments that will be maximally effective in reducing the interest rate risk and foreign currency exchange rate risk exposure that they are designated to hedge. This effectiveness is essential for qualifying for hedge accounting. Instruments that meet these hedging criteria are formally designated as hedges at the inception of the derivative contract. The Company uses a variety of commonly used derivative products that are considered “plain vanilla” derivatives. These derivatives typically include interest rate swaps, forward starting swaps, caps, collars and floors. The Company expressly prohibits the use of unconventional derivative instruments and the use of derivative instruments for trading or speculative purposes. Further, the Company has a policy of only entering into contracts with major financial institutions based upon their credit ratings and other factors. The Company recognizes all derivatives on the Consolidated Balance Sheets at fair value within other assets or other liabilities, depending on the balance at the end of the period. Derivatives that are not designated as hedges must be adjusted to fair value through income. If a derivative is designated and qualifies as a hedge, depending on the nature of the hedge, changes in the fair value of the derivative will be recognized in other comprehensive income until the hedged item is recognized in earnings. Prior to the Company’s adoption of ASU 2017-12 on January 1, 2018, described in Note 2 , the ineffective portion of the change in fair value of a derivative designated as a hedge was immediately recognized in earnings, however subsequent to adoption, the entire change in fair value is recognized in other comprehensive income until the hedged item is recognized in earnings. As a result of adoption, the Company recorded a decrease to its opening retained earnings balance and a corresponding increase to its opening accumulated other comprehensive income balance of $ 103 as of January 1, 2018, which represents the cumulative amount of hedge ineffectiveness recorded in the Consolidated Statements of Operations at the time of adoption. Derivative accounting may increase or decrease reported net income and shareholders’ equity prospectively, depending on future levels of the LIBOR swap spreads and other variables affecting the fair values of derivative instruments and hedged items, but will have no effect on cash flows, provided the contract is carried through to full term. Refer to Note 7 for additional information on the Company's derivative instruments, including the fair value measurement of these instruments. Borrowings on the Company’s multicurrency tranche of the 2015 Revolving Credit Facility, which are designated as non-derivative net investment hedges, are recognized at par value based on the exchange rate in effect on the date of the draw. Subsequent changes in the exchange rates of the Company’s non-derivative net investment hedges are recognized as part of the cumulative foreign currency translation adjustment within other comprehensive income. The Company’s derivatives and hedging instruments as of March 31, 2018 are as follows: Benchmark Rate Notional Value Strike Rate Effective Date Expiration Date Fair Value Interest Rate Swap - Waco 1 mo. USD-LIBOR-BBA 14,815 USD 4.55% 12/19/2013 12/19/2020 $ (13 ) Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.22% 12/19/2016 12/17/2018 615 Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.23% 12/19/2016 12/17/2018 612 Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.24% 12/19/2016 12/17/2018 604 Interest Rate Swap - 5-Year Term Loan 1 mo. USD-LIBOR-BBA 750,000 USD 1.60% 12/17/2015 12/17/2020 17,010 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 175,000 USD 1.82% 12/17/2015 1/9/2023 5,660 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 60,000 USD 1.95% 10/13/2017 1/9/2023 1,599 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 40,000 USD 2.01% 10/13/2017 1/9/2023 953 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 39,500 USD 1.96% 10/13/2017 1/9/2023 1,016 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 31,500 USD 1.96% 10/13/2017 1/9/2023 809 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 31,500 USD 2.00% 10/13/2017 1/9/2023 765 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 22,500 USD 1.95% 10/13/2017 1/9/2023 593 Forward Starting Swap 1 3 mo. USD-LIBOR-BBA 250,000 USD 2.23% 12/20/2017 12/20/2027 11,652 Net Investment Hedge in GBP-denominated investments USD-GBP exchange rate 9,000 GBP N/A 7/15/2016 N/A — Net Investment Hedge in EUR-denominated investments USD-EUR exchange rate 4,000 EUR N/A 3/8/2018 N/A — Total hedging instruments $ 41,875 1. The forward starting swap has a mandatory early termination date of June 20, 2018. As of March 31, 2018 , the Company’s derivative instruments consisted of interest rate swaps, which are cash flow hedges used to hedge exposure to variability in future interest payments on its debt facilities. The Company's interest rate swap derivative instruments were reported in other assets at fair value of $41,888 and in other liabilities at fair value of $(13) at March 31, 2018 . The table below details the location in the financial statements of the gain or loss recognized on the interest rate swaps designated as cash flow hedges for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Accumulated other comprehensive income: Gain recognized in accumulated other comprehensive income 1 $ 22,153 $ — Interest expense: Gain reclassified from accumulated other comprehensive income into interest expense 1 $ 268 $ 268 Gain recognized in interest expense (ineffective portion) 2 — 46 Total recognized in interest expense on statements of operations $ 268 $ 314 1. Periods prior to January 1, 2018, when the Company adopted ASU 2017-12, include only the effective portion and periods subsequent to January 1, 2018 include both the effective and ineffective portions as the two amounts are no longer separately measured and reported. The first quarter of 2018 includes $103 related to the adoption of ASU 2017-02. 2. Represents the ineffective portion and pertains only to periods prior to January 1, 2018, when the Company adopted ASU 2017-12. During the next 12 months, the Company expects that $(7,947) will be reclassified from other comprehensive income as an increase in interest expense for the Company’s interest rate swaps as of March 31, 2018 . Additionally, the Company will recognize $1,295 in interest expense on a straight-line basis over the remaining original term of terminated swaps through June 2019, representing amortization of the remaining accumulated other comprehensive income balance related to the swap, and of this amount $1,087 will be recognized in interest expense during the next 12 months. The Company hedges exposure to changes in the exchange rates underlying its investments based in foreign currencies using non-derivative net investment hedges in conjunction with borrowings under the multicurrency tranche of its 2015 Revolving Credit Facility. In March 2018, the Company entered into a non-derivative net investment hedge on its euro-denominated investment in the Gramercy European Property Fund III and in prior periods, from September 2015 until disposal of the underlying investments in July 2017, the Company had a non-derivative net investment hedge on its investments in the Gramercy European Property Fund and the Goodman Europe JV, all of which had euros as their functional currencies. The Company’s non-derivative net investment hedge on its British pound sterling-denominated investments, which was entered into in July 2016, is used to hedge exposure to changes in the British pound sterling U.S. dollar exchange rate underlying its unconsolidated equity investment in the Goodman UK JV, which has British pounds sterling as its functional currency. The Company’s non-derivative net investment hedge values are reported at carrying value and are included in the balance of the senior unsecured revolving credit facility on the Consolidated Balance Sheets. During the three months ended March 31, 2018 and 2017, the Company recorded a net loss of $459 and $923 , respectively, in other comprehensive income from the impact of exchange rates related to the non-derivative net investment hedges. When the non-derivative net investments being hedged are sold or substantially liquidated, the balance of the translation adjustment accumulated in other comprehensive income will be reclassified into earnings.

Shareholders' Equity (Deficit)

Shareholders' Equity (Deficit) of the Company	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Shareholders' Equity (Deficit) of the Company	Shareholders’ Equity (Deficit) of the Company As of March 31, 2018 and December 31, 2017 , the Company's authorized capital shares consisted of 500,000,000 shares of beneficial interest, $0.01 par value per share, of which the Company is authorized to issue up to 490,000,000 common shares of beneficial interest, $0.01 par value per share, or common shares, and 10,000,000 preferred shares of beneficial interest, $0.01 par value per share, or preferred shares. As of March 31, 2018 , 160,782,765 common shares and 3,500,000 preferred shares were issued and outstanding. In February 2018, the Company’s board of trustees authorized and the Company declared a dividend of $0.375 per common share for the first quarter of 2018, which was paid on April 16, 2018 to holders of record as of March 30, 2018 . Employee Share Purchase Plan In June 2017, the Company’s shareholders approved an Employee Share Purchase Plan, or ESPP, which enables the Company’s eligible employees to purchase the common shares through payroll deductions. The ESPP has a maximum of 250,000 common shares available for issuance and provides for eligible employees to purchase the common shares during defined offering periods at a purchase price determined at the discretion of the board of trustees, which has been initially established to be equal to 90.0% of the lower of either (i) the closing price of the Company’s common shares on the first day of the offering period and (ii) the closing price of the Company’s common shares on the last day of the offering period. As of March 31, 2018 , there were no shares issued under the ESPP. Dividend Reinvestment Plan In June 2016, the Company adopted a dividend reinvestment plan, or DRIP, under which shareholders may use their dividends and optional cash payments to purchase additional common shares of the Company. In August 2016, the Company registered 3,333,333 common shares related to the DRIP. During the three months ended March 31, 2018 , 1,811 shares were issued under the DRIP and as of March 31, 2018 there were 3,323,962 shares available for issuance under the DRIP. At-The-Market Equity Offering Program In July 2016, the Company’s board of trustees approved the establishment of an “at the market” equity issuance program, or ATM Program, pursuant to which the Company may offer and sell common shares with an aggregate gross sales price of up to $375,000 . During the three months ended March 31, 2018 , the Company did not sell any common shares through the ATM Program. Preferred Shares Holders of the Company's 7.125% Series A Preferred Shares, or Series A Preferred Shares, are entitled to receive annual dividends of $1.78125 per share on a quarterly basis and dividends are cumulative, subject to certain provisions. On or after August 15, 2019, the Company can, at its option, redeem the Series A Preferred Shares at par for cash. At March 31, 2018 , the Company had 3,500,000 of its Series A Preferred Shares outstanding with a mandatory liquidation preference of $25.00 per share. Equity Incentive Plans In June 2016, the Company instituted its 2016 Equity Incentive Plan, which was approved by the Company’s board of trustees and shareholders. As of March 31, 2018 , there were 2,634,080 shares available for grant under the 2016 Equity Incentive Plan. The Company accounts for share-based compensation awards using fair value recognition provisions and assumes an estimated forfeiture rate which impacts the amount of compensation cost recognized over the benefit period. Through March 31, 2018 , 1,129,130 restricted shares had been issued under the Company’s equity incentive plans, including the 2016 Equity Incentive Plan and the Company’s previous equity incentive plans, of which 67.2% have vested. As of March 31, 2018 and December 31, 2017 , the Company had 316,183 and 347,676 weighted average restricted shares outstanding, respectively. Compensation expense of $541 and $817 was recorded for the three months ended March 31, 2018 and 2017, respectively, related to the Company’s equity incentive plans. Compensation expense of $4,757 will be recorded over the course of the next 26 months representing the remaining weighted average vesting period of equity awards issued under the equity incentive plans as of March 31, 2018 . Compensation expense of $1,138 and $1,056 was recorded for the three months ended March 31, 2018 and 2017, respectively, for the Company's Outperformance Plans. Compensation expense of $10,188 will be recorded over the course of the next 35 months , representing the remaining weighted average vesting period of the awards issued under the Outperformance Plans as of March 31, 2018 . Earnings per Share The Company presents both basic and diluted earnings per share, or EPS. Basic EPS is computed by dividing net income available to common shareholders, as adjusted for unallocated earnings attributable to certain participating securities, if any, by the weighted average number of common shares outstanding during the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue common shares were exercised or converted into common shares, as long as their inclusion would not be anti-dilutive. The two-class method is an earnings allocation methodology that determines EPS for common shares and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The Company has certain share-based payment awards that contain nonforfeitable rights to dividends, which are considered participating securities for the purposes of computing EPS pursuant to the two-class method, and therefore the Company applies the two-class method in its computation of EPS. Earnings per share for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net income attributable to noncontrolling interest (802 ) (154 ) Less: Nonforfeitable dividends allocated to participating shareholders (203 ) (276 ) Less: Preferred share dividends (1,559 ) (1,559 ) Net income available to common shares outstanding $ 25,300 $ 7,292 Denominator – Weighted average shares: Basic weighted average shares outstanding 160,408,136 140,907,399 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average shares outstanding 160,416,900 141,875,619 The Company’s options and other share-based payment awards used in the computation of EPS were calculated using the treasury share method. As discussed in Note 5 , 100.0% of the Company’s Exchangeable Senior Notes were exchanged for 5,258,420 of the Company’s common shares in September 2017, however for the three months ended March 31, 2017, the Company had the intent and ability to settle the debt component of the Exchangeable Senior Notes in cash and the excess conversion premium in shares, thus for that period the Company only included the effect of the excess conversion premium in the calculation of Diluted EPS. For the three months ended March 31, 2018 and 2017, the net income attributable to the outside interests in the Operating Partnership has been excluded from the numerator and 5,040,730 and 620,586 , respectively, weighted average shares related to the outside interests in the Operating Partnership have been excluded from the denominator for the purpose of calculating Diluted EPS as there would have been no effect had such amounts been included. Refer to Note 11 for more information on the outside interests in the Operating Partnership. Accumulated other comprehensive income (loss) Accumulated other comprehensive income (loss) as of March 31, 2018 and December 31, 2017 is comprised of the following: March 31, 2018 December 31, 2017 Net unrealized gain on derivative securities $ 37,680 $ 15,630 Net unrealized gain on debt instruments 369 417 Foreign currency translation adjustments: Net gain on non-derivative net investment hedges 1 (162 ) 297 Other foreign currency translation adjustments (4,757 ) (5,734 ) Reclassification of swap gain into interest expense 2,434 2,166 Cumulative effect of accounting change 103 — Total accumulated other comprehensive income $ 35,667 $ 12,776 1. The foreign currency translation adjustment associated with the Company’s non-derivative net investment hedge related to its European investments is included in other comprehensive income (loss). The balance reflects write-offs of $1,851 on the Company’s non-derivative net investment hedge during the year ended December 31, 2017 .

Partners' Capital of the Operat

Partners' Capital of the Operating Partnership	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Partners' Capital of the Operating Partnership	Partners’ Capital of the Operating Partnership The Company is the sole general partner of the Operating Partnership. As of March 31, 2018 , the Company owned 160,782,765 of the outstanding general and limited partnership interests, or 96.75% , of the Operating Partnership. The number of common units in the Operating Partnership is equivalent to the number of outstanding common shares of the Company, and the entitlement of all the Operating Partnership’s common units to quarterly distributions and payments in liquidation are substantially the same as those of the Company's common shareholders. Similarly, in the case of each series of preferred units in the Operating Partnership held by the Company, there is a series of preferred shares that is equivalent in number and carries substantially the same terms as such series of the Operating Partnership’s preferred units. Limited Partner Units As of March 31, 2018 , limited partners other than the Company owned 5,388,995 common units, or 3.25% , of the Operating Partnership. Earnings per Unit The Operating Partnership's earnings per unit for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net gain attributable to noncontrolling interest in other partnerships — (120 ) Less: Nonforfeitable dividends allocated to participating unitholders (203 ) (276 ) Less: Preferred unit distributions (1,559 ) (1,559 ) Net income available to common units outstanding $ 26,102 $ 7,326 Denominator – Weighted average units: Basic weighted average units outstanding 165,448,866 141,527,985 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average units outstanding 165,457,630 142,496,205

Noncontrolling Interests

Noncontrolling Interests	3 Months Ended
	Mar. 31, 2018
Noncontrolling Interest [Abstract]
Noncontrolling Interests	Noncontrolling Interests Noncontrolling interests represent the outside equity interests in the Operating Partnership as well as third-party equity interests in the Company’s other consolidated subsidiaries. Outside equity interests in Operating Partnership The outside equity interests in the Operating Partnership include common units of limited partnership interest in the Operating Partnership, or OP Units, and the earned and vested portion of limited partnership interests in the Operating Partnership granted by the Company pursuant to its share-based compensation plans, or LTIP Units, which are convertible on a one-for-one basis into OP Units. The aggregate outstanding noncontrolling interest in the Operating Partnership as of March 31, 2018 represented an interest of approximately 3.25% in the Operating Partnership. A portion of the Operating Partnership’s net income (loss) during each reporting period is attributed to noncontrolling interests based on the weighted average percentage ownership of both OP Unit holders and earned and vested LTIP Unit holders relative to the sum of the Company’s total outstanding common shares, OP Units, and earned and vested LTIP Units. OP Units During the three months ended March 31, 2018 , the Company issued 996,098 OP Units as part of its contribution to fund its pro rata share of the E-Commerce JV’s acquisition of two properties. As of March 31, 2018 , 4,729,480 OP Units were outstanding, which can be redeemed for 4,729,480 of the Company's shares. During the three months ended March 31, 2018 and the year ended December 31, 2017 , 6,038 and 134,607 OP Units, respectively, were converted on a one-for-one basis into common shares of the Company. At March 31, 2018 , 4,729,480 common shares of the Company were reserved for issuance upon redemption of OP Units. OP Units are recorded at the greater of cost basis or fair market value based on the closing share price of the Company’s common shares at the end of the reporting period. As of March 31, 2018 , the value of the OP units was $137,800 . LTIP Units As of March 31, 2018 , noncontrolling interest owners held 659,515 earned and vested LTIP Units, which, upon conversion into OP Units, can be redeemed for 659,515 of the Company’s common shares. During the three months ended March 31, 2018 and year ended December 31, 2017 , there were no earned and vested LTIP Units converted into OP Units or redeemed for common shares of the Company. At March 31, 2018 , 659,515 common shares of the Company were reserved for issuance upon conversion of the earned and vested LTIP Units into OP Units and their subsequent redemption for common shares. Below is the rollforward of the activity relating to the noncontrolling interests in the Operating Partnership as of March 31, 2018 : Noncontrolling Interest Balance at January 1, 2018 $ 113,530 Issuance of noncontrolling interests in the Operating Partnership 25,142 Redemption of noncontrolling interests in the Operating Partnership (130 ) Net income attribution 802 Fair value adjustments 232 Dividends (1,776 ) Balance at March 31, 2018 $ 137,800 Interests in Other Entities There are entities that the Company consolidates into its Consolidated Financial Statements based on the structure of the entities and their control provisions. As of March 31, 2018 , the Company consolidated the Lakemont Development Investment and during the year ended December 31, 2017 until its dissolution in the fourth quarter of 2017, the Company consolidated European Fund Manager, which were both consolidated VIEs of the Company. The Company’s interest in these entities is presented in the equity section of its Consolidated Financial Statements. Refer to Note 2 for further discussion of these entities and consolidation considerations.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Funding Commitments As of March 31, 2018 , the Company is obligated to fund the development of one property and remaining improvements at three development properties, for which it has remaining cumulative future commitments of $59,104 . The Company has committed $64,257 ( €52,187 ) to the Gramercy European Property Fund III. The Company contributed $2,460 ( €1,977 ) to the Gramercy European Property Fund III as of March 31, 2018 . Foreign currency commitments have been converted into U.S. dollars based on (i) the foreign exchange rate at the closing date for completed transactions and (ii) the exchange rate that prevailed on March 31, 2018 , in the case of unfunded commitments. The Company has a 51.0% interest in the E-Commerce JV and has committed capital to fund its pro rata share of the E-Commerce JV’s initial acquisition of six properties, as well as the acquisition of additional properties in the future, subject to the partners' approval. The Company's pro rata funding commitment for the initial six properties is estimated at approximately $110,000 , which will be funded using a combination of OP Units and cash. As of March 31, 2018 , the Company contributed approximately $30,206 to the E-Commerce JV, of which $1,130 was contributed in cash. The Company has committed to fund $100,000 to Strategic Office Partners, of which $29,477 was funded as of March 31, 2018 and December 31, 2017. See Note 4 for further information on the Gramercy European Property Fund III, the E-Commerce JV, and Strategic Office Partners. Legal Proceedings The Company and/or one or more of its subsidiaries is party to various litigation matters that are considered routine litigation incidental to its or their business, none of which are considered material. Office Leases The Company has several office locations, which are each subject to operating lease agreements. These office locations include the Company’s corporate office at 90 Park Avenue, New York, New York, and the Company’s various regional offices located across the United States and Europe. Capital and Operating Ground Leases Certain properties acquired are subject to ground leases, which are accounted for as operating and capital leases, as applicable. The ground leases have varying ending dates, renewal options and rental rate escalations, with the latest lease extending to June 2053 . Future minimum rental payments to be made by the Company under these non-cancelable ground leases, excluding increases resulting from increases in the consumer price index, are as follows: April 1 to December 31, 2018 2019 2020 2021 2022 Thereafter Total Ground Leases - Operating $ 1,888 $ 2,593 $ 2,596 $ 2,567 $ 2,598 $ 73,175 $ 85,417 Ground Leases - Capital 1 — — — — 329 330 Total $ 1,889 $ 2,593 $ 2,596 $ 2,567 $ 2,598 $ 73,504 $ 85,747

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company has elected to be taxed as a REIT, under Sections 856 through 860 of the Internal Revenue Code beginning with its taxable year ended December 31, 2004. To qualify as a REIT, the Company must meet certain organizational and operational requirements, including a requirement to distribute annually at least 90.0% of its ordinary taxable income to its shareholders. As a REIT, the Company generally will not be subject to U.S. federal income tax on taxable income that it distributes to its shareholders. The Operating Partnership is a limited partnership and therefore is generally not liable for federal corporate income taxes as income is reported in the tax returns of its partners. The Operating Partnership may, however, be subject to certain state and local taxes. The Operating Partnership has in the past established taxable REIT subsidiaries, or TRSs, to effect various taxable transactions. Typical transactions that could cause these TRSs to be subject to federal, state and local taxes would include, but are not limited to, gains on property sales and management fee income. Tax expense from the Operating Partnership’s TRS for the three months ended March 31, 2018 and 2017 was immaterial. The Company’s policy for interest and penalties, if any, on material uncertain tax positions recognized in the financial statements is to classify these as interest expense and operating expense, respectively. As of March 31, 2018 and December 31, 2017 , the Company did not incur any material interest or penalties.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information The following table represents supplemental cash flow disclosures for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Supplemental cash flow disclosures: Interest paid $ 19,320 $ 17,447 Income taxes paid 60 71 Proceeds from 1031 exchanges from sale of real estate 5 23,219 Use of funds from 1031 exchanges for acquisitions of real estate (5 ) (23,218 ) Non-cash activity: Fair value adjustment to noncontrolling interest in the Operating Partnership $ 232 $ (296 ) Debt assumed in acquisition of real estate — 3,680 Debt transferred in disposition of real estate — (10,456 ) Non-cash acquisition of consolidated VIE — 24,930 Dividend reinvestment plan proceeds 46 81 Redemption of units of noncontrolling interest in the Operating Partnership for common shares (130 ) (2,164 ) Contributions to unconsolidated equity investments for units of noncontrolling interests in the operating partnership 25,141 —

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In April 2018, the Company declared a second quarter 2018 common dividend of $0.375 per share, payable on July 16, 2018 to shareholders of record as of June 29, 2018 . In April 2018, the Company also declared a second quarter 2018 dividend on its 7.125% Series A Preferred Shares in the amount of $0.44531 per share, payable on July 2, 2018 to preferred shareholders of record as of the close of business on June 19, 2018 . Subsequent to March 31, 2018, the Company closed on the disposition of a parcel of land for gross proceeds of approximately $975 . Subsequent to March 31, 2018, the Company issued 570,863 OP Units valued at approximately $16,663 in connection with its contribution to the E-Commerce JV for the acquisition of two properties.

Significant Accounting Polici24

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Quarterly Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP, for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In management’s opinion, all adjustments (consisting of normal recurring accruals) considered necessary for fair presentation have been included. The 2018 operating results for the period presented are not necessarily indicative of the results that may be expected for the year ending December 31, 2018 . These Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and accompanying notes included in the Annual Report on Form 10-K for the year ended December 31, 2017 of the Company and the Operating Partnership. The Consolidated Balance Sheets at December 31, 2017 were derived from the audited Consolidated Financial Statements at that date.
Reclassifications	Reclassifications Certain prior year balances have been reclassified to conform with the current year presentation. During the fourth quarter of 2017, the Company adopted Accounting Standards Update, or ASU, No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, which requires restricted cash and cash equivalents to be included with cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the Consolidated Statements of Cash Flows. As a result of the adoption, net cash provided by operating activities changed by $235 , net cash used in investing activities changed by $(947) , and net cash provided by financing activities changed by $909 , for the three months ended March 31, 2017 .
Principles of Consolidation	Principles of Consolidation The Consolidated Financial Statements include the Company’s accounts and those of the Company’s subsidiaries which are wholly-owned or controlled by the Company, or entities which are variable interest entities, or VIEs, in which the Company is the primary beneficiary. The primary beneficiary is the party that absorbs a majority of the VIE’s anticipated losses and/or a majority of the expected returns. The Company has evaluated its investments for potential classification as variable interests by evaluating the sufficiency of each entity’s equity investment at risk to absorb losses. Entities which the Company does not control and are considered VIEs, but where the Company is not the primary beneficiary, are accounted for under the equity method. All significant intercompany balances and transactions have been eliminated. The equity interests of other limited partners in the Company’s Operating Partnership are reflected as noncontrolling interests.
Real Estate Investments	Real Estate Investments Real Estate Acquisitions The Company evaluates its acquisitions of real estate, including equity interests in entities that predominantly hold real estate assets, to determine if the acquired assets meet the definition of a business and need to be accounted for as a business combination, or alternatively, should be accounted for as an asset acquisition. An integrated set of assets and activities acquired does not meet the definition of a business if either (i) substantially all the fair value of the gross assets acquired is concentrated in either a single identifiable asset or a group of similar identifiable assets, or (ii) the asset and activities acquired do not contain at least an input and a substantive process that together significantly contribute to the ability to create outputs. The Company expects that its acquisitions of real estate will continue to not meet the definition of a business. Acquisitions of real estate that do not meet the definition of a business, including sale-leaseback transactions that have newly-originated leases and real estate investments under construction, or build-to-suit investments, are recorded as asset acquisitions. The accounting for asset acquisitions is similar to the accounting for business combinations, except that the acquisition consideration, including acquisition costs, is allocated to the individual assets acquired and liabilities assumed on a relative fair value basis. Based on this allocation methodology, asset acquisitions do not result in the recognition of goodwill or a bargain purchase. The Company incurs internal transaction costs, which are direct, incremental internal costs related to acquisitions, that are recorded within general and administrative expense. Additionally, for build-to-suit investments in which the Company may engage a developer to construct a property or provide funds to a tenant to develop a property, the Company capitalizes the funds provided to the developer/tenant and real estate taxes, if applicable, during the construction period. To determine the fair value of assets acquired and liabilities assumed in an acquisition, which generally include land, building, improvements, and intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases at the acquisition date, the Company utilizes various estimates, processes and information to determine the as-if-vacant property value. Estimates of value are made using customary methods, including data from appraisals, comparable sales, and discounted cash flow analyses. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. The Company assesses the fair value of leases assumed at acquisition based upon estimated cash flow projections that utilize appropriate discount rates and available market information. Refer to the policy section "Intangible Assets and Liabilities" for more information on the Company’s accounting for intangibles. Depreciation is computed using the straight-line method over the shorter of the estimated useful life at acquisition of the capitalized item or 40 years for buildings, five to ten years for building equipment and fixtures, and the lesser of the useful life or the remaining lease term for tenant improvements and leasehold interests. Maintenance and repair expenditures are charged to expense as incurred. For transactions that qualify as business combinations, the Company recognizes the assets acquired and liabilities assumed at fair value, including the value of intangible assets and liabilities, and any excess or deficit of the consideration transferred relative to the fair value of the net assets acquired is recorded as goodwill or a bargain purchase gain, as appropriate. Acquisition costs of business combinations are expensed as incurred. Capital Improvements In leasing space, the Company may provide funding to the lessee through a tenant allowance. Certain improvements are capitalized when they are determined to increase the useful life of the building. During construction of qualifying projects, the Company capitalizes project management fees as permitted to be charged under the lease, if incremental and identifiable. In accounting for tenant allowances, the Company determines whether the allowance represents funding for the construction of leasehold improvements and evaluates the ownership of such improvements. If the Company is considered the owner of the leasehold improvements, the Company capitalizes the amount of the tenant allowance and depreciates it over the shorter of the useful life of the leasehold improvements or the lease term. If the tenant allowance represents a payment for a purpose other than funding leasehold improvements, or in the event the Company is not considered the owner of the improvements for accounting purposes, the allowance is considered to be a lease incentive and is recognized over the lease term as a reduction of rental revenue. Impairments and Disposals The Company reviews the recoverability of a property’s carrying value when circumstances indicate a possible impairment of the value of a property, such as an adverse change in future expected occupancy or a significant decrease in the market price of an asset. The review of recoverability is based on an estimate of the future undiscounted cash flows, excluding interest charges, expected to result from the property’s use and eventual disposition. These estimates consider factors such as changes in strategy resulting in an increased or decreased holding period, expected future operating income, market and other applicable trends and residual value, as well as the effects of leasing demand, competition and other factors. If management determines impairment exists due to the inability to recover the carrying value of a property, for properties to be held and used, an impairment loss is recorded to the extent that the carrying value exceeds the estimated fair value of the property and for assets held for sale, an impairment loss is recorded to the extent that the carrying value exceeds the fair value less estimated cost of disposal. These assessments are recorded as an impairment loss in the Consolidated Statements of Operations in the period the determination is made. The estimated fair value of the asset becomes its new cost basis. For a depreciable long-lived asset to be held and used, the new cost basis will be depreciated or amortized over the remaining useful life of that asset.
Cash and Cash Equivalents	Cash, Cash Equivalents, and Restricted Cash The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The Company's restricted cash primarily consists of reserves for certain capital improvements, leasing, interest and real estate tax and insurance payments as required by certain mortgage note obligations, as well as proceeds from property sales held by qualified intermediaries to be used for tax-deferred, like-kind exchanges under section 1031 of the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Consolidated Balance Sheets that sums to the total of the same such amounts shown in the Consolidated Statements of Cash Flows. As of March 31, 2018 2017 Cash and cash equivalents $ 41,964 $ 56,256 Restricted cash 15,041 13,101 Total cash, cash equivalents, and restricted cash $ 57,005 $ 69,357
Variable Interest Entities, Consolidated and Unconsolidated	The Company’s five consolidated VIEs as of March 31, 2018 and December 31, 2017 included the Operating Partnership and four land parcels in Fort Mill, South Carolina acquired by an investment entity formed in December 2017, on which it will fund the development of four industrial facilities, or the Lakemont Development Investment. The Company has a 95.0% interest in the Lakemont Development Investment and will acquire the seller’s retained 5.0% interest when the properties are developed and leased. As of March 31, 2018 and December 31, 2017 , the Company’s carrying value of the Lakemont Development Investment was $4,674 and $4,584 , respectively. Unconsolidated VIEs The Company’s two unconsolidated VIEs as of March 31, 2018 and December 31, 2017 included its retained non-investment grade subordinate bonds, preferred shares and ordinary shares of two collateralized debt obligations, or CDOs, which are collectively herein referred to as the Retained CDO Bonds. Refer to the “Other Assets” section of this Note 2 and also to Note 7 for more information on the accounting and valuation of the Retained CDO Bonds. As of March 31, 2018 and December 31, 2017 , the Company’s carrying value of the Retained CDO Bonds was $5,800 and $5,527 , respectively.
Tenant and Other Receivables	Tenant and Other Receivables Tenant and other receivables are derived from rental revenue, tenant reimbursements, and management fees. Rental revenue is recorded on a straight-line basis over the initial term of the lease. Since many leases provide for rental increases at specified intervals, straight-line basis accounting requires the Company to record a receivable, and include in revenues, unbilled rent receivables that will only be received if the tenant makes all rent payments required through the expiration of the initial term of the lease. Tenant and other receivables also include receivables related to tenant reimbursements for common area maintenance expenses and certain other recoverable expenses that are recognized as revenue in the period in which the related expenses are incurred. Tenant and other receivables are recorded net of the allowances for doubtful accounts, which as of March 31, 2018 and December 31, 2017 were $670 and $638 , respectively. The Company continually reviews receivables related to rent, tenant reimbursements, and management fees, including incentive fees, and determines collectability by taking into consideration the tenant or asset management clients’ payment history, the financial condition of the tenant or asset management client, business conditions in the industry in which the tenant or asset management client operates and economic conditions in the area in which the property or asset management client is located. In the event that the collectability of a receivable is in doubt, the Company increases the allowance for doubtful accounts or records a direct write-off of the receivable, as appropriate.
Intangible Assets and Liabilities	Intangible Assets and Liabilities As discussed above in policy section, "Real Estate Acquisitions," the Company follows the acquisition method of accounting for its asset acquisitions and business combinations and thus allocates the purchase price of acquired properties to tangible and identifiable intangible assets acquired based on their respective fair values. Identifiable intangible assets include amounts allocated to acquired leases for above- and below-market lease rates and the value of in-place leases. Management also considers information obtained about each property as a result of its pre-acquisition due diligence. Above-market and below-market lease values for properties acquired are recorded based on the present value of the difference between the contractual amount to be paid pursuant to each in-place lease and management’s estimate of the fair market lease rate for each such in-place lease, measured over a period equal to the remaining non-cancelable term of the lease. The present value calculation utilizes a discount rate that reflects the risks associated with the leases acquired. The above-market and below-market lease values are amortized as a reduction of and increase to rental revenue, respectively, over the remaining non-cancelable terms of the respective leases. If a tenant terminates its lease prior to its contractual expiration and no future rental payments will be received, any unamortized balance of the market lease intangibles will be written off to rental revenue. The aggregate value of in-place leases represents the costs of leasing costs, other tenant related costs, and lost revenue that the Company did not have to incur by acquiring a property that is already occupied. Factors considered by management in its analysis of the in-place lease intangibles include an estimate of carrying costs during the expected lease-up period for each property taking into account current market conditions and costs to execute similar leases. In estimating carrying costs, management includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the anticipated lease-up period. Management also estimates costs to execute similar leases including leasing commissions and other related expenses. The value of in-place leases is amortized to depreciation and amortization expense over the remaining non-cancelable term of the respective leases. In no event does the amortization period for intangible assets exceed the remaining depreciable life of the building. If a tenant terminates its lease prior to its contractual expiration and no future rental payments will be received, any unamortized balance of the in-place lease intangible will be written off to depreciation and amortization expense. Above-market and below-market ground rent intangibles are recorded for properties acquired in which the Company is the lessee pursuant to a ground lease assumed at acquisition. The above-market and below-market ground rent intangibles are valued similarly to above-market and below-market leases, except that, because the Company is the lessee as opposed to the lessor, the above-market and below-market ground lease values are amortized as a reduction of and increase to rent expense, respectively, over the remaining non-cancelable terms of the respective leases.
Revenue Recognition	Revenue Adoption of ASC Topic 606, "Revenue from Contracts with Customers" The Company adopted ASC Topic 606, which is described below in the section “Recently Issued Accounting Pronouncements,” on January 1, 2018 using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under the new guidance, while prior period amounts are not adjusted and continue to be reported in accordance with the historic accounting guidance in ASC Topic 605. As a result of adoption, the Company recorded an increase to its opening retained earnings balance of $663 as of January 1, 2018, which represents the cumulative impact of the new guidance and is related to the Company’s sale of real estate to Strategic Office Partners in 2016. There was no impact to revenues recorded for the three months ended March 31, 2018 as a result of adoption of the new revenue guidance. Revenue Recognition The Company recognizes revenue when control of the promised goods or services is transferred to a customer, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company’s primary sources of revenue include rental revenue, third-party management fees, operating expense reimbursements, and other income, which are disaggregated on the Consolidated Statements of Operations and are described in detail below. Real Estate Investments Rental revenue from leases on real estate investments is recognized on a straight-line basis over the term of the lease, regardless of when payments are contractually due. For leases on properties that are under construction at the time of acquisition, the Company begins recognition of rental revenue upon completion of construction of the leased asset and delivery of the leased asset to the tenant. The Company’s lease agreements with tenants also generally contain provisions that require tenants to reimburse the Company for real estate taxes, insurance costs, common area maintenance costs, and other property-related expenses. Under lease arrangements in which the Company is the primary obligor for these expenses, the Company recognizes such amounts as both revenues and operating expenses. Under lease arrangements in which the tenant pays these expenses directly, such amounts are not included in revenues or expenses. These reimbursement amounts are recognized in the period in which the related expenses are incurred. Management Fees The Company’s asset and property management agreements may contain provisions for fees related to dispositions, administration of the assets including fees related to accounting, valuation and legal services, and management of capital improvements or projects on the underlying assets. The Company recognizes revenue for fees pursuant to its management agreements in the period in which they are earned. Deferred revenue from management fees received prior to the date earned are included in other liabilities on the Consolidated Balance Sheets. For management fee agreements that include multiple performance obligations, the Company allocates revenue to each performance obligation based on its relative standalone selling price, which is primarily determined based on the prices charged to customers. Certain of the Company’s asset management contracts and agreements with its unconsolidated equity investments include provisions that allow it to earn additional fees, generally described as incentive fees or promoted interests, based on the achievement of a targeted valuation or the achievement of a certain internal rate of return on the managed assets held by third parties or the equity investment. The Company’s incentive fees are accounted for as variable consideration and revenue is recognized for them based on the Company’s estimate of the expected amount to which it will be entitled in exchange for its services. The Company recognizes promoted interest in the period in which it is determined to be appropriately earned pursuant to the terms of the specific agreement. The values of incentive fees and promoted interest fees are periodically evaluated by management. Other Income Other income primarily consists of income accretion on the Company’s Retained CDO Bonds, realized foreign currency exchange gains (losses), and interest income.
Foreign Currency	Foreign Currency The Company's European management platform performs asset and property management services in Europe. The Company has unconsolidated equity investments in Europe and Asia and previously had two wholly-owned properties in Canada until their dispositions in March 2017. The Company also has borrowings outstanding in euros and British pounds sterling under the multicurrency portion of its revolving credit facility. Refer to Note 4 for more information on the Company’s foreign unconsolidated equity investments.
Other Assets	Other Assets The Company includes prepaid expenses, capitalized software costs, contract intangible assets, deferred costs, loan investments, goodwill, derivative assets, and Retained CDO Bonds in other assets. Loan Investments The Company may originate loans related to specific real estate development projects. In October 2017, the Company entered into an agreement to provide a mezzanine construction loan facility with a maximum commitment of $250,000 to an industrial developer as borrower. As of March 31, 2018 and December 31, 2017, the carrying value of the Company’s loan investments was $22,437 and $22,154 , respectively, which represents the cost, net of accumulated amortization of loan costs. A s of March 31, 2018 , the loan investments had a weighted average interest rate of 10.47% . The Company evaluates its loan investments for possible credit losses each period. There were no loan reserves recorded during the three months ended March 31, 2018 and all of the Company’s loan investments were performing in accordance with the terms of the relevant investments as of March 31, 2018 .
Goodwill	Goodwill The Company recognized goodwill of $3,802 related to the acquisition of Gramercy Europe Limited, which it adjusts each reporting period for the effect of foreign currency translation adjustments and tests for impairment on an annual basis, or more frequently if events or changes in circumstances indicate that the asset might be impaired. The carrying value of goodwill at March 31, 2018 and December 31, 2017 was $3,394 and $3,272 , respectively. The Company did no t record any impairment on its goodwill during the three months ended March 31, 2018 .
Retained CDO Bonds	Retained CDO Bonds The Retained CDO Bonds are non-investment grade subordinate bonds, preferred shares and ordinary shares of two CDOs. Management estimated the timing and amount of cash flows expected to be collected and recognized an investment in the Retained CDO Bonds equal to the net present value of these discounted cash flows. There is no guarantee that the Company will realize any proceeds from this investment, or what the timing will be for the expected remaining life of the Retained CDO Bonds. The Company considers these investments to be not of high credit quality and does not expect a full recovery of interest and principal. Therefore, the Company has suspended interest income accruals on these investments. The Company classifies the Retained CDO Bonds as available for sale. On a quarterly basis, the Company evaluates the Retained CDO Bonds to determine whether significant changes in estimated cash flows or unrealized losses on these investments, if any, reflect a decline in value which is other-than-temporary. If there is a decrease in estimated cash flows and the investment is in an unrealized loss position, the Company will record an other-than-temporary impairment, or OTTI, in the Consolidated Statements of Operations. To determine the component of the OTTI related to expected credit losses, the Company compares the amortized cost basis of the Retained CDO Bonds to the present value of the revised expected cash flows, discounted using the pre-impairment effective yield. Conversely, if the security is in an unrealized gain position and there is a decrease or significant increase in expected cash flows, the Company will prospectively adjust the yield using the effective yield method. Refer to Note 7 for further discussion regarding the fair value measurement of the Retained CDO Bonds.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash investments, debt investments and accounts receivable. The Company places its cash investments in excess of insured amounts with high quality financial institutions. Concentrations of credit risk also arise when a number of the Company’s tenants or asset management clients are engaged in similar business activities or are subject to similar economic risks or conditions that could cause their inability to meet contractual obligations to the Company. The Company regularly monitors its portfolio to assess potential concentrations of credit risk. Management believes the current credit risk portfolio is reasonably well diversified. During the three months ended March 31, 2018 and 2017, there were no tenants that accounted for 10.0% or more of the Company's rental revenue. Additionally, for the three months ended March 31, 2018 , there were three states, Illinois , Texas , and Florida , that each accounted for 10.0% or more of the Company’s rental revenue.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09 (Topic 606), Revenue from Contracts with Customers, which is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to customers in an amount reflecting the consideration it expects to receive in exchange for those goods or services. In April 2016 and February 2017, the FASB issued ASU 2016-10 and ASU 2017-05, respectively, which further clarified the new revenue recognition guidance under ASC Topic 606. The Company adopted the guidance on January 1, 2018 using the modified retrospective method, which did not have a material impact on its Consolidated Financial Statements. Refer to the “Revenue” section above for further detail. In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. The guidance requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to record changes in instruments specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. The update is effective for fiscal years beginning after December 15, 2017, and for interim periods therein. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. Refer to Note 8 for more information. I n February 2016, the FASB issued ASU 2016-02, Leases, which 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 update will be effective beginning in the first quarter of 2019 and early adoption is permitted. The new standard requires a modified retrospective transition approach for all leases existing at, or entered into after, the date of initial application, with an option to use certain transition relief. The Company’s accounting for leases in which it is a lessor, which represents most of its leasing arrangements, will be largely unchanged under ASU 2016-02; however, the Company is a lessee in several operating and ground leases and the accounting for these arrangements is more significantly impacted by the new standard. Pursuant to the new guidance, lessees are required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. The Company is continuing to evaluate the impact of adopting the new leases standard on its Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows Classification of Certain Cash Receipts and Cash Payments, which serves to reduce the diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The update is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation: Scope of Modification Accounting. The amendment provides guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting. The guidance is effective for annual and interim periods beginning after December 15, 2017, with early adoption permitted under certain circumstances. The Company adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on its Consolidated Financial Statements. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. The transition guidance provides companies with the option of early adopting the new standard using a modified retrospective transition method in any interim period after issuance of the update, or alternatively requires adoption for fiscal years beginning after December 15, 2018. In the first quarter of 2018, the Company early adopted this standard and the adoption did not have a material impact on its Consolidated Financial Statements.

Real Estate Investments Real Es

Real Estate Investments Real Estate Investments (Tables)	3 Months Ended
	Mar. 31, 2018
Real Estate [Abstract]
Schedule of Real Estate Investments	Investments in real estate properties consisted of the following: March 31, 2018 December 31, 2017 Square feet 1 Number of properties Investment Square feet 1 Number of properties Investment Operating properties 2 80,884,942 360 $ 5,811,702 82,146,063 363 $ 5,857,906 Land parcels 2 7,075 2 7,075 Less accumulated depreciation (368,815 ) (333,151 ) Total operating properties and land parcels $ 5,449,962 $ 5,531,830 Development properties 1,503,300 5 12,092 1,630,022 6 22,843 Total 82,388,242 367 $ 5,462,054 83,776,085 371 $ 5,554,673 1. Represents rentable square feet for operating properties and projected rentable square feet upon completion for development properties. 2. Includes development properties that have been completed as of the end of the period.
Summary of Acquisitions	Real estate acquisition activity for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Number of operating properties 1 7 Rentable square feet of operating properties 162,056 2,257,311 Total purchase price of all acquisitions $ 10,550 $ 124,672
Summary of Dispositions	Real estate disposition activity for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Number of properties 1 5 7 Rentable square feet 1,546,091 487,872 Gross proceeds $ 111,012 $ 51,683 Impairment of real estate investments related to asset dispositions during the period 2 $ — $ — Net gain on disposals $ 16,255 $ 17,377 1. During the three months ended March 31, 2018, the Company sold five properties and one warehouse from another asset. 2. Although there were no impairments recognized related to assets disposed during the three months ended March 31, 2018 and 2017 , as presented in the table, the Company recognized impairments on real estate investments of $12,771 during the three months ended March 31, 2017 related to properties held as of March 31, 2017, for which the Company determined there were nonrecoverable declines in value.
Summary of Intangibles	Intangible assets and liabilities consisted of the following: Weighted average amortization period (years) March 31, 2018 December 31, 2017 Intangible assets: In-place leases, net of accumulated amortization of $214,664 and $194,836 9.3 $ 513,423 $ 545,782 Above-market leases, net of accumulated amortization of $26,854 and $25,229 6.8 43,979 46,713 Below-market ground rent, net of accumulated amortization of $421 and $408 17.5 5,811 6,064 Total intangible assets $ 563,213 $ 598,559 Intangible liabilities: Below-market leases, net of accumulated amortization of $30,685 and $28,516 39.5 $ 152,758 $ 159,652 Above-market ground rent, net of accumulated amortization of $516 and $462 32.0 6,786 6,839 Total intangible liabilities $ 159,544 $ 166,491
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table provides the projected amortization expense of the intangible assets and liabilities for the next five years: April 1 to December 31, 2018 2019 2020 2021 2022 Depreciation and amortization expense $ 70,211 $ 84,228 $ 70,822 $ 59,528 $ 46,652 Rental revenue increase $ (1,571 ) $ (2,520 ) $ (4,004 ) $ (4,168 ) $ (6,260 )

Significant Accounting Polici26

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Schedule of Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Consolidated Balance Sheets that sums to the total of the same such amounts shown in the Consolidated Statements of Cash Flows. As of March 31, 2018 2017 Cash and cash equivalents $ 41,964 $ 56,256 Restricted cash 15,041 13,101 Total cash, cash equivalents, and restricted cash $ 57,005 $ 69,357
Schedule of Retained Collateralized Debt Obligation Bonds	A summary of the Company’s Retained CDO Bonds as of March 31, 2018 is as follows: Number of Securities Face Value Amortized Cost Gross Unrealized Gain Other-Than-Temporary Impairment Fair Value Weighted Average Expected Life (years) 6 $ 329,597 $ 5,431 $ 369 $ — $ 5,800 1.1

Unconsolidated Equity Investm27

Unconsolidated Equity Investments (Tables)	3 Months Ended
	Mar. 31, 2018
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Equity Method Investments	As of March 31, 2018 and December 31, 2017 , the Company owned properties through unconsolidated equity investments and had investment interests in these unconsolidated entities as follows: As of March 31, 2018 As of December 31, 2017 Investment Ownership % Voting Interest % Partner Investment in Unconsolidated Equity Investment 1 No. of Properties Investment in Unconsolidated Equity Investment 1 No. of Properties Strategic Office Partners 25.0 % 25.0 % TPG Real Estate $ 28,792 13 $ 28,243 13 E-Commerce JV 51.0 % 50.0 % Ample Glow Investments 43,502 2 17,798 — Goodman UK JV 80.0 % 50.0 % Goodman Group 15,980 1 15,768 1 Gramercy European Property Fund III 19.9 % 50.0 % Various 5,363 2 2,949 — Other 2 5.1% - 50.0% 5.1% - 50.0% Various 5,476 3 5,456 3 Total $ 99,113 21 $ 70,214 17 1. The amounts presented include a basis difference of $2,011 and $1,943 , net of accumulated amortization, for the Goodman UK JV as of March 31, 2018 and December 31, 2017 , respectively. The amounts presented include a basis difference of $(3,916) , net of accumulated amortization, for the E-Commerce JV as of March 31, 2018 . 2. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV.
Summary Investment Holdings	The following is a summary of the Company’s unconsolidated equity investments for the three months ended March 31, 2018 : Unconsolidated Equity Investments Balance at January 1, 2018 $ 70,214 Contributions to unconsolidated equity investments 28,731 Equity in net loss of unconsolidated equity investments, including adjustments for basis differences (926 ) Other comprehensive income of unconsolidated equity investments 431 Cumulative effect of accounting change 663 Balance at March 31, 2018 $ 99,113
Schedule of Combined Balance Sheet for the Company's Joint Venture	The following are the balance sheets for the Company’s unconsolidated equity investments at March 31, 2018 : Strategic Office Partners E-Commerce JV Goodman UK JV Gramercy European Property Fund III Other 1 Assets: Real estate assets, net 2 $ 264,099 $ 149,895 $ 19,150 $ 62,284 $ 108,993 Other assets 80,897 48,894 1,751 5,428 18,421 Total assets $ 344,996 $ 198,789 $ 20,901 $ 67,712 $ 127,414 Liabilities and members' equity: Mortgage notes payable $ 213,699 $ 108,473 $ — $ 35,873 $ 38,341 Other liabilities 16,698 5,018 732 4,850 19,043 Total liabilities 230,397 113,491 732 40,723 57,384 Company's equity 28,792 43,502 15,980 5,363 5,476 Other members' equity 85,807 41,796 4,189 21,626 64,554 Liabilities and members' equity $ 344,996 $ 198,789 $ 20,901 $ 67,712 $ 127,414 1. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV. 2. Includes basis adjustments recorded by the Company to adjust the unconsolidated equity investments to fair value. The following are the balance sheets for the Company’s unconsolidated equity investments at December 31, 2017 : Strategic Office Partners E-Commerce JV Goodman UK JV Other 1 Assets: Real estate assets, net 2 $ 265,014 $ — $ 18,633 $ 107,949 Other assets 78,243 35,727 1,473 34,022 Total assets $ 343,257 $ 35,727 $ 20,106 $ 141,971 Liabilities and members' equity: Mortgage notes payable $ 213,205 $ — $ — $ 38,662 Other liabilities 15,002 830 203 19,329 Total liabilities 228,207 830 203 57,991 Company's equity 28,243 17,798 15,768 8,405 Other members' equity 86,807 17,099 4,135 75,575 Liabilities and members' equity $ 343,257 $ 35,727 $ 20,106 $ 141,971 1. Includes CBRE Strategic Partners Asia, the Philips JV, the Morristown JV, and the Gramercy European Property Fund III. 2. Includes basis adjustments recorded by the Company to adjust the unconsolidated equity investments to fair value.
Schedule of Long-term Debt	The following is a summary of the secured financing arrangements within the Company’s unconsolidated equity investments as of March 31, 2018 : Outstanding Balance 2 Property Unconsolidated Equity Investment Economic Ownership Interest Rate 1 Maturity Date March 31, 2018 December 31, 2017 Strategic Office Partners Facility 1 3 Strategic Office Partners 25.0% 4.70% 10/7/2019 $ 169,380 $ 169,380 Strategic Office Partners Facility 2 4 Strategic Office Partners 25.0% 9.21% 10/8/2020 39,540 39,540 E-Commerce JV Facility 4 E-Commerce JV 51.0% 3.38% 2/10/2023 109,846 — Gramercy European Property Fund III Facility 4 Gramercy European Property Fund III 19.9% 1.57% 3/12/2023 36,084 — Henderson, NV Strategic Office Partners 25.0% 4.75% 8/6/2025 8,593 8,636 Somerset, NJ Philips JV 25.0% 6.90% 9/11/2035 38,341 38,662 Total mortgage notes payable $ 401,784 $ 256,218 Net deferred financing costs and net debt discount (5,398 ) (4,351 ) Total mortgage notes payable, net $ 396,386 $ 251,867 1. Represents the current effective rate as of March 31, 2018 , including the swapped interest rate for mortgage notes that have interest rate swaps. The current interest rate is not adjusted to include the amortization of fair market value premiums or discounts. 2. Mortgage notes are presented at 100.0% of the amount held by the unconsolidated equity investment. 3. As of March 31, 2018 , there were ten properties under this mortgage note. 4. As of March 31, 2018 , there were two properties under each of these mortgage notes.
Schedule of Combined Income Statement for the Company's Joint Venture	The following are the statements of operations for the Company’s unconsolidated equity investments for the three months ended March 31, 2018 : Strategic Office Partners E-Commerce JV Goodman UK JV Gramercy European Property Fund III Other 1 Revenues $ 11,143 $ 2,165 $ — $ 482 $ 1,994 Operating expenses 4,151 583 260 682 106 Interest expense 3,113 669 — 97 666 Depreciation and amortization 4,823 862 206 209 333 Total expenses 12,087 2,114 466 988 1,105 Net income (loss) from operations (944 ) 51 (466 ) (506 ) 889 Gain on derivatives 492 — — — — Loss on extinguishment of debt — (1,200 ) — — Net income (loss) $ (452 ) $ (1,149 ) $ (466 ) $ (506 ) $ 889 Company's share in net income (loss) $ 26 $ (520 ) $ (373 ) $ (93 ) $ 20 Adjustments for REIT basis — 18 (4 ) — — Company's equity in net income (loss) within continuing operations $ 26 $ (502 ) $ (377 ) $ (93 ) $ 20 1. Includes CBRE Strategic Partners Asia, the Philips JV, and the Morristown JV. The following are the statements of operations for the Company’s unconsolidated equity investments for the three months ended March 31, 2017 : Gramercy European Property Fund 1 Goodman Europe JV Gramercy European Property Fund 2 Total Strategic Office Partners Goodman UK JV Other 3 Revenues $ 4,955 $ 10,118 $ 15,073 $ 5,526 $ 295 $ (1,331 ) Operating expenses 922 2,951 3,873 1,474 302 576 Interest expense 672 1,474 2,146 1,510 — 641 Depreciation and amortization 2,021 4,473 6,494 2,503 375 333 Total expenses 3,615 8,898 12,513 5,487 677 1,550 Net income (loss) from operations 1,340 1,220 2,560 39 (382 ) (2,881 ) Gain (loss) on derivatives — 1,221 1,221 (349 ) — — Provision for taxes (17 ) 146 129 — (8 ) — Net income (loss) $ 1,323 $ 2,587 $ 3,910 $ (310 ) $ (390 ) $ (2,881 ) Company’s share in net income (loss) $ 67 $ 446 $ 513 $ (15 ) $ (312 ) $ (155 ) Adjustments for REIT basis (36 ) — (36 ) — (89 ) — Company’s equity in net income (loss) within continuing operations $ 31 $ 446 $ 477 $ (15 ) $ (401 ) $ (155 ) 1. As of and for the three months ended March 31, 2017 , the Company had a 5.1% direct interest in the Goodman Europe JV as well as an indirect interest in the remaining 94.9% interest that was held through the Company’s 14.2% interest in the Gramercy European Property Fund. For the three months ended March 31, 2017 , the Company’s equity in net income (loss) from the entities is based on these ownership interest percentages during the period. 2. Excludes the results of the Gramercy European Property Fund’s 94.9% interest in the Goodman Europe JV, as the Goodman Europe JV is separately presented. 3. Includes CBRE Strategic Partners Asia, the Philips JV, the Morristown JV, and European Fund Carry Co.

Debt Obligations (Tables)

Debt Obligations (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Schedule of Mortgage Notes Payable	The following is a summary of the Company’s secured financing arrangements as of March 31, 2018 and December 31, 2017 : Property Interest Rate 1 Maturity Date Outstanding Balance March 31, 2018 December 31, 2017 Greenwood, IN 3.59% 6/15/2018 $ 7,211 $ 7,257 Greenfield, IN 3.63% 6/15/2018 5,828 5,865 Logistics Portfolio - Pool 3 2 3.96% 8/1/2018 43,302 43,302 Philadelphia, PA 4.99% 1/1/2019 11,842 11,943 Bridgeview, IL 3.90% 5/1/2019 5,792 5,838 Spartanburg, SC 3.20% 6/1/2019 530 632 Charleston, SC 3.11% 8/1/2019 320 457 Lawrence, IN 5.02% 1/1/2020 19,896 20,061 Charlotte, NC 3.28% 1/1/2020 1,363 1,538 Hawthorne, CA 3.52% 8/1/2020 17,042 17,207 Charleston, SC 3.32% 10/1/2020 696 758 Charleston, SC 2.97% 10/1/2020 684 746 Charleston, SC 3.37% 10/1/2020 684 746 Charlotte, NC 3.38% 10/1/2020 594 647 Des Plaines, IL 5.54% 10/31/2020 2,365 2,385 Waco, TX 4.75% 12/19/2020 14,815 14,890 Deerfield, IL 3.71% 1/1/2021 10,355 10,447 Winston-Salem, NC 3.41% 6/1/2021 3,135 3,354 Winston-Salem, NC 3.42% 7/1/2021 1,043 1,114 Logistics Portfolio - Pool 1 2 4.27% 1/1/2022 37,856 38,107 CCC Portfolio 2 4.24% 10/6/2022 22,691 22,814 Logistics Portfolio - Pool 4 2 4.36% 12/5/2022 79,500 79,500 Romeoville, IL 3.80% 4/6/2023 24,835 24,951 Romeoville, IL 3 9.37% 4/6/2023 6,613 6,623 KIK USA Portfolio 2 4.31% 7/6/2023 7,077 7,154 Yuma, AZ 5.27% 12/6/2023 11,804 11,858 Allentown, PA 5.16% 1/6/2024 22,586 22,690 Spartanburg, SC 3.72% 2/1/2024 5,447 5,635 Natick, MA 5.21% 3/1/2024 31,121 31,224 Natick, MA 3 10.38% 3/1/2024 3,458 3,469 Maple Grove, MN 3.88% 5/6/2024 16,291 16,380 Curtis Bay, MD 4.31% 7/1/2024 13,500 13,500 Rialto, CA 3.91% 8/1/2024 54,543 54,741 Houston, TX 3.68% 9/1/2024 26,000 26,000 Durham, NC 4.02% 9/6/2024 3,614 3,631 Charleston, SC 3.80% 2/1/2025 5,831 6,001 Hackettstown, NJ 5.49% 3/6/2026 9,420 9,455 Hutchins, TX 5.41% 6/1/2029 21,269 21,578 Total mortgage notes payable $ 550,953 $ 554,498 Net deferred financing costs and net debt premium 8,520 9,023 Total mortgage notes payable, net $ 559,473 $ 563,521 1. Represents the interest rate as of March 31, 2018 that was recorded for financial reporting purposes, which reflects the effect of interest rate swaps and amortization of financing costs and fair market value premiums or discounts. 2. As of March 31, 2018, there were two properties under the Logistics Portfolio - Pool 3 mortgage, three properties under the Logistics Portfolio - Pool 1 mortgage, five properties under the CCC Portfolio mortgage, six properties under the Logistics Portfolio - Pool 4 mortgage, and three properties under the KIK USA Portfolio mortgage.
Schedule of Line of Credit Facilities	The terms of the Company’s unsecured debt obligations and outstanding balances as of March 31, 2018 and December 31, 2017 are set forth in the table below: Stated Interest Rate Effective Interest Rate 1 Maturity Date Outstanding Balance March 31, 2018 December 31, 2017 2015 Revolving Credit Facility - USD tranche 2.89 % 2.89 % 1/8/2020 $ 275,000 $ 345,000 2015 Revolving Credit Facility - Multicurrency tranche 1.32 % 1.32 % 1/8/2020 17,543 12,162 3-Year Term Loan 2.91 % 2.33 % 1/8/2019 300,000 300,000 5-Year Term Loan 2.91 % 2.70 % 1/8/2021 750,000 750,000 7-Year Term Loan 2.76 % 3.00 % 1/9/2023 400,000 400,000 2015 Senior Unsecured Notes 4.97 % 5.07 % 12/17/2024 150,000 150,000 2016 Senior Unsecured Notes 3.89 % 4.00 % 12/15/2022 150,000 150,000 2016 Senior Unsecured Notes 4.26 % 4.38 % 12/15/2025 100,000 100,000 2016 Senior Unsecured Notes 4.32 % 4.43 % 12/15/2026 100,000 100,000 Total unsecured debt 2,242,543 2,307,162 Net deferred financing costs and net debt discount (4,872 ) (5,063 ) Total unsecured debt, net $ 2,237,671 $ 2,302,099 1. Represents the rate at which interest expense is recorded for financial reporting purposes as of March 31, 2018 , which reflects the effect of interest rate swaps and amortization of financing costs and fair market value premiums or discounts.
Schedule of Maturities of Long-term Debt	Combined aggregate principal maturities of the Company’s unsecured debt obligations and non-recourse mortgages, in addition to associated interest payments, as of March 31, 2018 are as follows: April 1 to December 31, 2018 2019 2020 2021 2022 Thereafter Above market interest Total 2015 Revolving Credit Facility $ — $ — $ 292,543 $ — $ — $ — $ — $ 292,543 Term Loans — 300,000 — 750,000 — 400,000 — 1,450,000 Mortgage Notes Payable 1 66,599 30,450 62,834 19,256 141,929 229,885 — 550,953 Senior Unsecured Notes — — — — 150,000 350,000 — 500,000 Interest Payments 2 82,144 97,025 87,135 57,199 53,364 64,772 3,648 445,287 Total $ 148,743 $ 427,475 $ 442,512 $ 826,455 $ 345,293 $ 1,044,657 $ 3,648 $ 3,238,783 1. Mortgage note payments reflect accelerated repayment dates, when applicable, pursuant to the related agreement. 2. Interest payments do not reflect the effect of interest rate swaps.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Carrying Value and Fair Value of Financial Instruments	The following table presents the carrying value in the financial statements and approximate fair value of assets and liabilities measured on a recurring and non-recurring basis at March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Financial assets: Interest rate swaps $ 41,888 $ 41,888 $ 19,668 $ 19,668 Retained CDO Bonds 5,800 5,800 5,527 5,527 Real estate investments 1 — — 87,996 87,996 Investment in CBRE Strategic Partners Asia 2,869 2,869 2,820 2,820 Loan investments 2 22,437 20,990 22,154 21,362 Financial liabilities: Interest rate swaps $ 13 $ 13 $ 173 $ 173 Long-term debt: 2015 Revolving Credit Facility 2 292,543 292,492 357,162 357,369 3-Year Term Loan 2 300,000 300,090 300,000 300,091 5-Year Term Loan 2 750,000 750,653 750,000 750,678 7-Year Term Loan 2 398,241 400,020 398,152 400,010 Mortgage notes payable 2 559,473 565,329 563,521 573,826 Senior Unsecured Notes 2 496,887 502,349 496,785 513,229 1. Amount represents seven real estate investments that were impaired by the Company and held as of December 31, 2017 . 2. Long-term debt instruments are classified as Level III due to the significance of unobservable inputs which are based upon management assumptions.
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Assets and liabilities measured at fair value on a recurring and non-recurring basis are categorized as follows: At March 31, 2018 Total Level I Level II Level III Financial Assets: Retained CDO Bonds $ 5,800 $ — $ — $ 5,800 Investment in CBRE Strategic Partners Asia 2,869 — — 2,869 Interest rate swaps 41,888 — — 41,888 $ 50,557 $ — $ — $ 50,557 Financial Liabilities: Interest rate swaps $ (13 ) $ — $ — $ (13 ) $ (13 ) $ — $ — $ (13 ) At December 31, 2017 Total Level I Level II Level III Financial Assets: Retained CDO Bonds $ 5,527 $ — $ — $ 5,527 Real estate investments 87,996 — — 87,996 Investment in CBRE Strategic Partners Asia 2,820 — — 2,820 Interest rate swaps 19,668 — — 19,668 $ 116,011 $ — $ — $ 116,011 Financial Liabilities: Interest rate swaps $ (173 ) $ — $ — $ (173 ) $ (173 ) $ — $ — $ (173 )
Fair Value, Assets and Liabilities Measured on Recurring Basis, Valuation Techniques	Quantitative information regarding the valuation techniques and the range of significant unobservable Level III inputs used to determine fair value measurements on a recurring basis as of March 31, 2018 are as follows: Financial Asset (Liability) Fair Value Valuation Technique Unobservable Inputs Range Non-investment grade, subordinate CDO bonds $ 5,800 Discounted cash flows Discount rate 19.0% Investment in CBRE Strategic Partners Asia 2,869 Discounted cash flows Discount rate 20.0% Interest rate swaps 1 41,875 Hypothetical derivative method Credit borrowing spread 110 to 190 basis points 1. Fair value includes interest rate swap liabilities with an aggregate value of $(13) .
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following rollforward table reconciles the beginning and ending balances of financial assets (liabilities) measured at fair value on a recurring basis using Level III inputs as of March 31, 2018 : Retained CDO Bonds Investment in CBRE Strategic Partners Asia Interest Rate Swaps Total Financial Assets (Liabilities) - Level III Balance at January 1, 2018 $ 5,527 $ 2,820 $ 19,495 $ 27,842 Amortization of discounts or premiums 321 — 330 651 Adjustments to fair value: Unrealized gain on derivatives — — 22,050 22,050 Unrealized loss in other comprehensive income from fair value adjustment (48 ) — — (48 ) Total gain on fair value adjustments — 49 — 49 Balance at March 31, 2018 $ 5,800 $ 2,869 $ 41,875 $ 50,544
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following rollforward table reconciles the beginning and ending balances of financial assets (liabilities) measured at fair value on a recurring basis using Level III inputs as of March 31, 2018 : Retained CDO Bonds Investment in CBRE Strategic Partners Asia Interest Rate Swaps Total Financial Assets (Liabilities) - Level III Balance at January 1, 2018 $ 5,527 $ 2,820 $ 19,495 $ 27,842 Amortization of discounts or premiums 321 — 330 651 Adjustments to fair value: Unrealized gain on derivatives — — 22,050 22,050 Unrealized loss in other comprehensive income from fair value adjustment (48 ) — — (48 ) Total gain on fair value adjustments — 49 — 49 Balance at March 31, 2018 $ 5,800 $ 2,869 $ 41,875 $ 50,544

Derivatives and Non-Derivativ30

Derivatives and Non-Derivative Hedging Instruments (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The Company’s derivatives and hedging instruments as of March 31, 2018 are as follows: Benchmark Rate Notional Value Strike Rate Effective Date Expiration Date Fair Value Interest Rate Swap - Waco 1 mo. USD-LIBOR-BBA 14,815 USD 4.55% 12/19/2013 12/19/2020 $ (13 ) Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.22% 12/19/2016 12/17/2018 615 Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.23% 12/19/2016 12/17/2018 612 Interest Rate Swap - 3-Year Term Loan 1 mo. USD-LIBOR-BBA 100,000 USD 1.24% 12/19/2016 12/17/2018 604 Interest Rate Swap - 5-Year Term Loan 1 mo. USD-LIBOR-BBA 750,000 USD 1.60% 12/17/2015 12/17/2020 17,010 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 175,000 USD 1.82% 12/17/2015 1/9/2023 5,660 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 60,000 USD 1.95% 10/13/2017 1/9/2023 1,599 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 40,000 USD 2.01% 10/13/2017 1/9/2023 953 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 39,500 USD 1.96% 10/13/2017 1/9/2023 1,016 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 31,500 USD 1.96% 10/13/2017 1/9/2023 809 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 31,500 USD 2.00% 10/13/2017 1/9/2023 765 Interest Rate Swap - 7-Year Term Loan 1 mo. USD-LIBOR-BBA 22,500 USD 1.95% 10/13/2017 1/9/2023 593 Forward Starting Swap 1 3 mo. USD-LIBOR-BBA 250,000 USD 2.23% 12/20/2017 12/20/2027 11,652 Net Investment Hedge in GBP-denominated investments USD-GBP exchange rate 9,000 GBP N/A 7/15/2016 N/A — Net Investment Hedge in EUR-denominated investments USD-EUR exchange rate 4,000 EUR N/A 3/8/2018 N/A — Total hedging instruments $ 41,875 1. The forward starting swap has a mandatory early termination date of June 20, 2018.
Gain (Loss) Recognized On Interest Rate Swaps	The table below details the location in the financial statements of the gain or loss recognized on the interest rate swaps designated as cash flow hedges for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Accumulated other comprehensive income: Gain recognized in accumulated other comprehensive income 1 $ 22,153 $ — Interest expense: Gain reclassified from accumulated other comprehensive income into interest expense 1 $ 268 $ 268 Gain recognized in interest expense (ineffective portion) 2 — 46 Total recognized in interest expense on statements of operations $ 268 $ 314 1. Periods prior to January 1, 2018, when the Company adopted ASU 2017-12, include only the effective portion and periods subsequent to January 1, 2018 include both the effective and ineffective portions as the two amounts are no longer separately measured and reported. The first quarter of 2018 includes $103 related to the adoption of ASU 2017-02. 2. Represents the ineffective portion and pertains only to periods prior to January 1, 2018, when the Company adopted ASU 2017-12.

Shareholders' Equity (Deficit31

Shareholders' Equity (Deficit) of the Company (Tables)	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	Earnings per share for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net income attributable to noncontrolling interest (802 ) (154 ) Less: Nonforfeitable dividends allocated to participating shareholders (203 ) (276 ) Less: Preferred share dividends (1,559 ) (1,559 ) Net income available to common shares outstanding $ 25,300 $ 7,292 Denominator – Weighted average shares: Basic weighted average shares outstanding 160,408,136 140,907,399 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average shares outstanding 160,416,900 141,875,619 The Operating Partnership's earnings per unit for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net gain attributable to noncontrolling interest in other partnerships — (120 ) Less: Nonforfeitable dividends allocated to participating unitholders (203 ) (276 ) Less: Preferred unit distributions (1,559 ) (1,559 ) Net income available to common units outstanding $ 26,102 $ 7,326 Denominator – Weighted average units: Basic weighted average units outstanding 165,448,866 141,527,985 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average units outstanding 165,457,630 142,496,205
Schedule of Accumulated Other Comprehensive Income (Loss)	Accumulated other comprehensive income (loss) as of March 31, 2018 and December 31, 2017 is comprised of the following: March 31, 2018 December 31, 2017 Net unrealized gain on derivative securities $ 37,680 $ 15,630 Net unrealized gain on debt instruments 369 417 Foreign currency translation adjustments: Net gain on non-derivative net investment hedges 1 (162 ) 297 Other foreign currency translation adjustments (4,757 ) (5,734 ) Reclassification of swap gain into interest expense 2,434 2,166 Cumulative effect of accounting change 103 — Total accumulated other comprehensive income $ 35,667 $ 12,776 1. The foreign currency translation adjustment associated with the Company’s non-derivative net investment hedge related to its European investments is included in other comprehensive income (loss). The balance reflects write-offs of $1,851 on the Company’s non-derivative net investment hedge during the year ended December 31, 2017 .

Partners' Capital of the Oper32

Partners' Capital of the Operating Partnership (Tables)	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	Earnings per share for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net income attributable to noncontrolling interest (802 ) (154 ) Less: Nonforfeitable dividends allocated to participating shareholders (203 ) (276 ) Less: Preferred share dividends (1,559 ) (1,559 ) Net income available to common shares outstanding $ 25,300 $ 7,292 Denominator – Weighted average shares: Basic weighted average shares outstanding 160,408,136 140,907,399 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average shares outstanding 160,416,900 141,875,619 The Operating Partnership's earnings per unit for the three months ended March 31, 2018 and 2017 are computed as follows: Three Months Ended March 31, 2018 2017 Numerator – Income (loss): Net income (loss) from continuing operations $ 11,609 $ (8,072 ) Net loss from discontinued operations — (24 ) Net income (loss) before net gain on disposals 11,609 (8,096 ) Net gain on disposals 16,255 17,377 Net income 27,864 9,281 Less: Net gain attributable to noncontrolling interest in other partnerships — (120 ) Less: Nonforfeitable dividends allocated to participating unitholders (203 ) (276 ) Less: Preferred unit distributions (1,559 ) (1,559 ) Net income available to common units outstanding $ 26,102 $ 7,326 Denominator – Weighted average units: Basic weighted average units outstanding 165,448,866 141,527,985 Effect of dilutive securities: Unvested non-participating share based payment awards — 71,848 Options 8,764 15,576 Exchangeable Senior Notes — 880,796 Diluted weighted average units outstanding 165,457,630 142,496,205

Noncontrolling Interests (Table

Noncontrolling Interests (Tables)	3 Months Ended
	Mar. 31, 2018
Noncontrolling Interest [Abstract]
Noncontrolling Interest in the Operating Partnership	Below is the rollforward of the activity relating to the noncontrolling interests in the Operating Partnership as of March 31, 2018 : Noncontrolling Interest Balance at January 1, 2018 $ 113,530 Issuance of noncontrolling interests in the Operating Partnership 25,142 Redemption of noncontrolling interests in the Operating Partnership (130 ) Net income attribution 802 Fair value adjustments 232 Dividends (1,776 ) Balance at March 31, 2018 $ 137,800

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments	Future minimum rental payments to be made by the Company under these non-cancelable ground leases, excluding increases resulting from increases in the consumer price index, are as follows: April 1 to December 31, 2018 2019 2020 2021 2022 Thereafter Total Ground Leases - Operating $ 1,888 $ 2,593 $ 2,596 $ 2,567 $ 2,598 $ 73,175 $ 85,417 Ground Leases - Capital 1 — — — — 329 330 Total $ 1,889 $ 2,593 $ 2,596 $ 2,567 $ 2,598 $ 73,504 $ 85,747

Supplemental Cash Flow Inform35

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Schedule of Supplemental Cash Flow Activities	The following table represents supplemental cash flow disclosures for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Supplemental cash flow disclosures: Interest paid $ 19,320 $ 17,447 Income taxes paid 60 71 Proceeds from 1031 exchanges from sale of real estate 5 23,219 Use of funds from 1031 exchanges for acquisitions of real estate (5 ) (23,218 ) Non-cash activity: Fair value adjustment to noncontrolling interest in the Operating Partnership $ 232 $ (296 ) Debt assumed in acquisition of real estate — 3,680 Debt transferred in disposition of real estate — (10,456 ) Non-cash acquisition of consolidated VIE — 24,930 Dividend reinvestment plan proceeds 46 81 Redemption of units of noncontrolling interest in the Operating Partnership for common shares (130 ) (2,164 ) Contributions to unconsolidated equity investments for units of noncontrolling interests in the operating partnership 25,141 —

Business and Organization (Narr

Business and Organization (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)ft²buildingProperty	Mar. 31, 2017ft²Property	Dec. 31, 2017Property
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties	367		371
Number of Acquisitions	1
Purchase Price | $	$ 10,550
Number of properties	5	7
Rentable square feet | ft²	1,546,091	487,872
Proceeds from sale of property held-for-sale | $	$ 111,012
Wholly Owned Properties
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties | building	362
Area of real estate property | ft²	80,884,942
Occupancy rate	97.30%
Unconsolidated Properties
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties | building	20
GPT Operating Partnership LP
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Ownership percentage by noncontrolling owners	3.25%
Gramercy Asset Management | Commercial Lease Properties
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Commercial real estate assets | $	$ 1,960,000
Europe | Gramercy Asset Management | Commercial Lease Properties
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Commercial real estate assets | $	$ 1,408,000
CBRE Strategic Partners Asia
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties	1
Development Property
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of Acquisitions	1
Rentable square feet of operating properties | ft²	126,722
Disposed by Sale
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties	5
Rentable square feet | ft²	1,546,091
Disposed by Sale | Offices
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of properties	1

Real Estate Investments (Schedu

Real Estate Investments (Schedule of Real Estate Investments) (Details) $ in Thousands	Mar. 31, 2018USD ($)ft²Property	Dec. 31, 2017USD ($)ft²Property
Real Estate [Line Items]
Rentable area (in sqft) | ft²	82,388,242	83,776,085
Number of properties | Property	367	371
Operating properties	$ 5,811,702	$ 5,857,906
Land parcels	7,075	7,075
Less: accumulated depreciation	(368,815)	(333,151)
Total operating properties and land parcels	5,449,962	5,531,830
Development properties	12,092	22,843
Total real estate investments, net	$ 5,462,054	$ 5,554,673
Operating parcels
Real Estate [Line Items]
Rentable area (in sqft) | ft²	80,884,942	82,146,063
Number of properties | Property	360	363
Land parcels
Real Estate [Line Items]
Number of properties | Property	2	2
Development properties
Real Estate [Line Items]
Rentable area (in sqft) | ft²	1,503,300	1,630,022
Number of properties | Property	5	6

Real Estate Investments (Summar

Real Estate Investments (Summary of Asset Acquisitions) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)ft²Property	Mar. 31, 2017USD ($)ft²Property
Real Estate [Line Items]
Number of Acquisitions	1
Total purchase price of all acquisitions | $	$ 10,550	$ 124,672
Operating Properties
Real Estate [Line Items]
Number of operating properties	1	7
Rentable square feet of operating properties | ft²	162,056	2,257,311
Development Property
Real Estate [Line Items]
Number of Acquisitions	1
Rentable square feet of operating properties | ft²	126,722

Significant Accounting Polici39

Significant Accounting Policies (Narrative) (Details)	1 Months Ended	3 Months Ended
	Dec. 31, 2017USD ($)Propertyentity	Mar. 31, 2018USD ($)Propertyentitycollateralized_debt_obligations	Mar. 31, 2017USD ($)Property	Dec. 31, 2016USD ($)
Accounting Policies [Line Items]
Retained Earnings (Accumulated Deficit)	$ (1,369,872,000)	$ (1,404,416,000)
Net Cash Provided by (Used in) Operating Activities		$ 72,823,000	$ 58,479,000
Number of consolidated VIEs | entity	5	5
Number of Acquisitions | Property		1
Number of unconsolidated variable interest entities | entity	2	2
Number Of Investments Held | collateralized_debt_obligations		2
Contributions to unconsolidated equity investments		$ 28,731,000
Allowance for doubtful accounts receivable	$ 638,000	$ 670,000
Number of properties | Property	371	367
Impairment of goodwill		$ 0
Net Cash Provided by (Used in) Investing Activities		73,380,000	(87,638,000)
Net Cash Provided by (Used in) Financing Activities		(132,290,000)	18,188,000
Available-for-sale Securities
Accounting Policies [Line Items]
Retained collateralized debt obligations (CDOs) bonds, other-than-temporary impairment		$ 0	$ 4,890,000
Lakemont Development Investment
Accounting Policies [Line Items]
Number of Acquisitions | Property	4
Economic Ownership		95.00%
Ownership percentage by noncontrolling owners		5.00%
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net	$ 4,584,000	$ 4,674,000
Gramercy Europe Asset | Canada
Accounting Policies [Line Items]
Number of properties | Property			2
Retained CDO Bonds
Accounting Policies [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net	5,527,000	5,800,000
Gramercy Europe Limited
Accounting Policies [Line Items]
Goodwill	3,272,000	$ 3,394,000		$ 3,802,000
Building
Accounting Policies [Line Items]
Property, plant and equipment, useful life		40 years
Building Equipment and Fixtures | Minimum
Accounting Policies [Line Items]
Property, plant and equipment, useful life		5 years
Building Equipment and Fixtures | Maximum
Accounting Policies [Line Items]
Property, plant and equipment, useful life		10 years
ASU 2016-18
Accounting Policies [Line Items]
Net Cash Provided by (Used in) Operating Activities			$ 235,000
Net Cash Provided by (Used in) Investing Activities			(947,000)
Net Cash Provided by (Used in) Financing Activities			$ 909,000
ASU 2014-09
Accounting Policies [Line Items]
Retained Earnings (Accumulated Deficit)	663,000
Construction Loans
Accounting Policies [Line Items]
Loans and Leases Receivable, Maximum Borrowing Capacity		$ 250,000,000
Loans and Leases Receivable, Net Amount	$ 22,154,000	$ 22,437,000
Loans Receivable, Basis Spread on Variable Rate, During Period		10.47%

Real Estate Investments (Summ40

Real Estate Investments (Summary of Dispositions) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)ft²Property	Mar. 31, 2017USD ($)ft²Property
Real Estate [Abstract]
Number of properties | Property	5	7
Rentable square feet | ft²	1,546,091	487,872
Gross proceeds	$ 111,012	$ 51,683
Impairment of real estate investments related to asset dispositions during the period	0	0
Net gain on disposals	16,255	17,377
Impairment of real estate investments	$ 0	$ (12,771)

Significant Accounting Polici41

Significant Accounting Policies (Components of Cash, Cash Equivalents and Restricted Cash) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Cash and cash equivalents	$ 41,964	$ 30,231	$ 56,256
Restricted cash	15,041	12,723	13,101
Total cash, cash equivalents, and restricted cash	$ 57,005	$ 42,954	$ 69,357	$ 80,433

Real Estate Investments (Narrat

Real Estate Investments (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)ft²Property	Mar. 31, 2017USD ($)ft²Property
Real Estate [Line Items]
Amortization of Intangible Assets	$ 26,159	$ 24,172
Real estate acquisitions	10,197
Intangible assets acquisitions	$ 635
Number of properties | Property	5	7
Rentable square feet | ft²	1,546,091	487,872
Net gain on disposals	$ 16,255	$ 17,377
Impairment of real estate investments	$ 0	(12,771)
Number of Acquisitions | Property	1
Amortization of market lease intangible assets and liabilities	$ 494	$ 621
Assets Held-for-sale
Real Estate [Line Items]
Number of properties held-for-sale | Property	1
Net asset value	$ 402

Significant Accounting Polici43

Significant Accounting Policies (Schedule of Retained Collateralized Debt Obligation Bonds) (Details) - Available-for-sale Securities $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)security	Mar. 31, 2017USD ($)
Schedule of Available-for-sale Securities [Line Items]
Number of Securities | security	6
Face Value	$ 329,597
Amortized Cost	5,431
Gross Unrealized Gain	369
Other-than-temporary impairment	0	$ (4,890)
Fair Value	$ 5,800
Weighted Average Expected Life	1 year 1 month 6 days

Real Estate Investments (Summ44

Real Estate Investments (Summary of Intangibles) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Intangible assets:
Total intangible assets	$ 563,213	$ 598,559
Finite-lived intangible assets, accumulated amortization	241,939	220,473
Intangible liabilities:
Total intangible liabilities	$ 159,544	166,491
In-place leases
Real Estate [Line Items]
Weighted average amortization period (years)	9 years 3 months 19 days
Intangible assets:
Total intangible assets	$ 513,423	545,782
Finite-lived intangible assets, accumulated amortization	$ 214,664	194,836
Above-market leases
Real Estate [Line Items]
Weighted average amortization period (years)	6 years 9 months 18 days
Intangible assets:
Total intangible assets	$ 43,979	46,713
Finite-lived intangible assets, accumulated amortization	$ 26,854	25,229
Below-market ground rent
Real Estate [Line Items]
Weighted average amortization period (years)	17 years 6 months
Intangible assets:
Total intangible assets	$ 5,811	6,064
Finite-lived intangible assets, accumulated amortization	$ 421	408
Below-market leases
Real Estate [Line Items]
Weighted average amortization period (years)	39 years 6 months
Intangible liabilities:
Total intangible liabilities	$ 152,758	159,652
Finite-lived intangible liabilities, accumulated amortization	$ 30,685	28,516
Above-market ground rent
Real Estate [Line Items]
Weighted average amortization period (years)	32 years
Intangible liabilities:
Total intangible liabilities	$ 6,786	6,839
Finite-lived intangible liabilities, accumulated amortization	516	462
Assets Held-for-sale
Intangible assets:
Finite-lived intangible assets, accumulated amortization	0	0
Intangible liabilities:
Finite-lived intangible liabilities, accumulated amortization	$ 0	$ 0

Real Estate Investments (Sche45

Real Estate Investments (Schedule of Finite-Lived Intangible Assets, Future Amortization Expense) (Details) $ in Thousands	Mar. 31, 2018USD ($)
Depreciation and amortization expense
April 1 to December 31, 2018	$ 70,211
2,019	84,228
2,020	70,822
2,021	59,528
2,022	46,652
Rental revenue increase
April 1 to December 31, 2018	(1,571)
2,019	(2,520)
2,020	(4,004)
2,021	(4,168)
2,022	$ (6,260)

Unconsolidated Equity Investm46

Unconsolidated Equity Investments (Narrative) (Details) € in Thousands, $ in Thousands	Jun. 30, 2016	Nov. 30, 2017USD ($)Property	Mar. 31, 2018USD ($)Property	Mar. 31, 2018EUR (€)Property	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)Property	Mar. 31, 2018EUR (€)Property	Oct. 31, 2017USD ($)	Oct. 31, 2017EUR (€)	Jul. 31, 2017
Investments in and Advances to Affiliates [Line Items]
Number of properties | Property			367			371	367
Investment in unconsolidated equity investment			$ 99,113			$ 70,214
Contributions to unconsolidated equity investments			28,731
Distributions received from unconsolidated equity investments			$ 0		$ 352
Number of Acquisitions | Property			1	1
Gramercy European Property Fund
Investments in and Advances to Affiliates [Line Items]
Ownership %						14.20%
Goodman Europe JV
Investments in and Advances to Affiliates [Line Items]
Ownership %						5.10%				5.10%
Strategic Office Partners
Investments in and Advances to Affiliates [Line Items]
Distributions received from unconsolidated equity investments			$ 2,710
Commitment amount			400,000
Strategic Office Partners | Parent Company
Investments in and Advances to Affiliates [Line Items]
Commitment amount			100,000
E-Commerce JV
Investments in and Advances to Affiliates [Line Items]
Contributions to unconsolidated equity investments			30,206
Commitment amount			110,000
Number of Acquisitions | Property		6				6
Partnership unit contributions to investment		$ 80,000	25,141
Cash contributions to equity method investment		$ 30,000	1,130
Duke JV
Investments in and Advances to Affiliates [Line Items]
Ownership interest transferred	100.00%
Gramercy European Property Fund III
Investments in and Advances to Affiliates [Line Items]
Aggregate cost								$ 323,359	€ 262,622
Payments to investments			2,460	€ 1,977
Gramercy European Property Fund III | Parent Company
Investments in and Advances to Affiliates [Line Items]
Aggregate cost			$ 64,257				€ 52,187
Gramercy European Property Fund | Goodman Europe JV
Investments in and Advances to Affiliates [Line Items]
Ownership %						94.90%

Unconsolidated Equity Investm47

Unconsolidated Equity Investments (Summary of Unconsolidated Equity Investments) (Details) $ in Thousands	Mar. 31, 2018USD ($)Property	Dec. 31, 2017USD ($)Property	Jul. 31, 2017
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated equity investment	$ 99,113	$ 70,214
Number of properties | Property	367	371
E-Commerce JV
Schedule of Equity Method Investments [Line Items]
Basis difference	$ (3,916)
Gramercy European Property Fund
Schedule of Equity Method Investments [Line Items]
Ownership %		14.20%
Goodman Europe JV
Schedule of Equity Method Investments [Line Items]
Ownership %		5.10%	5.10%
Goodman Europe JV | Gramercy European Property Fund
Schedule of Equity Method Investments [Line Items]
Ownership %		94.90%
Goodman UK JV
Schedule of Equity Method Investments [Line Items]
Basis difference	2,011	$ 1,943
Unconsolidated Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated equity investment	$ 99,113	$ 70,214
Number of properties | Property	21	17
Unconsolidated Equity Method Investments | E-Commerce JV
Schedule of Equity Method Investments [Line Items]
Ownership %	51.00%
Voting Interest %	50.00%
Investment in unconsolidated equity investment	$ 43,502	$ 17,798
Number of properties | Property	2	0
Unconsolidated Equity Method Investments | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Ownership %	25.00%
Voting Interest %	25.00%
Investment in unconsolidated equity investment	$ 28,792	$ 28,243
Number of properties | Property	13	13
Unconsolidated Equity Method Investments | Goodman UK JV
Schedule of Equity Method Investments [Line Items]
Ownership %	80.00%
Voting Interest %	50.00%
Investment in unconsolidated equity investment	$ 15,980	$ 15,768
Number of properties | Property	1	1
Unconsolidated Equity Method Investments | Gramercy European Property Fund III
Schedule of Equity Method Investments [Line Items]
Ownership %	19.90%
Voting Interest %	50.00%
Investment in unconsolidated equity investment	$ 5,363	$ 2,949
Number of properties | Property	2	0
Unconsolidated Equity Method Investments | Other
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated equity investment	$ 5,476	$ 5,456
Number of properties | Property	3	3
Minimum | Unconsolidated Equity Method Investments | Other
Schedule of Equity Method Investments [Line Items]
Ownership %	5.10%
Voting Interest %	5.10%
Maximum | Unconsolidated Equity Method Investments | Other
Schedule of Equity Method Investments [Line Items]
Ownership %	50.00%
Voting Interest %	50.00%

Unconsolidated Equity Investm48

Unconsolidated Equity Investments (Rollforward of Unconsolidated Equity Investments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Beginning balance	$ 70,214
Contributions to unconsolidated equity investments	28,731
Equity in net loss of unconsolidated equity investments, including adjustments for basis differences	(926)	$ (94)
Other comprehensive income of unconsolidated equity investments	431
Cumulative effect of accounting change	663
Ending Balance	$ 99,113

Unconsolidated Equity Investm49

Unconsolidated Equity Investments (Combined Balance Sheets for the Company's Joint Ventures) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Jul. 31, 2017
Gramercy European Property Fund
Liabilities and members' equity:
Ownership %		14.20%
Goodman Europe JV
Liabilities and members' equity:
Ownership %		5.10%	5.10%
Goodman Europe JV | Gramercy European Property Fund
Liabilities and members' equity:
Ownership %		94.90%
Corporate Joint Venture | E-Commerce JV
Assets:
Real estate assets, net	$ 149,895	$ 0
Other assets	48,894	35,727
Total assets	198,789	35,727
Liabilities and members' equity:
Mortgage notes payable	108,473	0
Other liabilities	5,018	830
Total liabilities	113,491	830
Company's equity	43,502	17,798
Other members' equity	41,796	17,099
Liabilities and members' equity	198,789	35,727
Corporate Joint Venture | Gramercy European Property Fund
Assets:
Real estate assets, net	62,284
Other assets	5,428
Total assets	67,712
Liabilities and members' equity:
Mortgage notes payable	35,873
Other liabilities	4,850
Total liabilities	40,723
Company's equity	5,363
Other members' equity	21,626
Liabilities and members' equity	67,712
Corporate Joint Venture | Strategic Office Partners
Assets:
Real estate assets, net	264,099	265,014
Other assets	80,897	78,243
Total assets	344,996	343,257
Liabilities and members' equity:
Mortgage notes payable	213,699	213,205
Other liabilities	16,698	15,002
Total liabilities	230,397	228,207
Company's equity	28,792	28,243
Other members' equity	85,807	86,807
Liabilities and members' equity	344,996	343,257
Corporate Joint Venture | Goodman UK JV
Assets:
Real estate assets, net	19,150	18,633
Other assets	1,751	1,473
Total assets	20,901	20,106
Liabilities and members' equity:
Mortgage notes payable	0	0
Other liabilities	732	203
Total liabilities	732	203
Company's equity	15,980	15,768
Other members' equity	4,189	4,135
Liabilities and members' equity	20,901	20,106
Corporate Joint Venture | Other
Assets:
Real estate assets, net	108,993	107,949
Other assets	18,421	34,022
Total assets	127,414	141,971
Liabilities and members' equity:
Mortgage notes payable	38,341	38,662
Other liabilities	19,043	19,329
Total liabilities	57,384	57,991
Company's equity	5,476	8,405
Other members' equity	64,554	75,575
Liabilities and members' equity	$ 127,414	$ 141,971

Unconsolidated Equity Investm50

Unconsolidated Equity Investments (Real Estate Assets Subject to Mortgages) (Details) $ in Thousands	Mar. 31, 2018USD ($)Property	Dec. 31, 2017USD ($)
Schedule of Equity Method Investments [Line Items]
Percentage of face amount of debt presented	100.00%
Wholly Owned Properties | Strategic Office Partners Portfolio Facility One | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Economic Ownership	25.00%
Number of real estate properties pledged under debt | Property	10
Wholly Owned Properties | Strategic Office Partners Portfolio Facility Two | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Economic Ownership	25.00%
Wholly Owned Properties | E-Commerce JV Portfolio Facility | E-Commerce JV
Schedule of Equity Method Investments [Line Items]
Economic Ownership	51.00%
Wholly Owned Properties | Gramercy European Property Fund III Facility | Gramercy European Property Fund III
Schedule of Equity Method Investments [Line Items]
Economic Ownership	19.90%
Number of real estate properties pledged under debt | Property	2
Wholly Owned Properties | Henderson, NV | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Economic Ownership	25.00%
Wholly Owned Properties | Somerset, NJ | Philips JV
Schedule of Equity Method Investments [Line Items]
Economic Ownership	25.00%
Mortgages
Schedule of Equity Method Investments [Line Items]
Total mortgage notes payable, net	$ 550,953
Mortgages | Wholly Owned Properties
Schedule of Equity Method Investments [Line Items]
Outstanding Balance	401,784	$ 256,218
Net deferred financing costs and net debt discount	(5,398)	(4,351)
Total mortgage notes payable, net	$ 396,386	251,867
Mortgages | Wholly Owned Properties | Strategic Office Partners Portfolio Facility One | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Interest Rate	4.70%
Outstanding Balance	$ 169,380	169,380
Mortgages | Wholly Owned Properties | Strategic Office Partners Portfolio Facility Two | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Interest Rate	9.21%
Outstanding Balance	$ 39,540	39,540
Mortgages | Wholly Owned Properties | E-Commerce JV Portfolio Facility | E-Commerce JV
Schedule of Equity Method Investments [Line Items]
Interest Rate	3.38%
Outstanding Balance	$ 109,846	0
Mortgages | Wholly Owned Properties | Gramercy European Property Fund III Facility | Gramercy European Property Fund III
Schedule of Equity Method Investments [Line Items]
Interest Rate	1.57%
Outstanding Balance	$ 36,084	0
Mortgages | Wholly Owned Properties | Henderson, NV | Strategic Office Partners
Schedule of Equity Method Investments [Line Items]
Interest Rate	4.75%
Outstanding Balance	$ 8,593	8,636
Mortgages | Wholly Owned Properties | Somerset, NJ | Philips JV
Schedule of Equity Method Investments [Line Items]
Interest Rate	6.90%
Outstanding Balance	$ 38,341	$ 38,662

Unconsolidated Equity Investm51

Unconsolidated Equity Investments (Combined Income Statement for the Company's Joint Ventures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	$ (926)	$ (94)
Distributions received from unconsolidated equity investments	0	352
Gramercy European Property Fund
Investments in and Advances to Affiliates [Line Items]
Ownership %			14.20%
Strategic Office Partners
Investments in and Advances to Affiliates [Line Items]
Distributions received from unconsolidated equity investments	2,710
Corporate Joint Venture | Gramercy European Property Fund
Investments in and Advances to Affiliates [Line Items]
Revenues	482	15,073
Operating expenses	682	3,873
Interest expense	97	2,146
Depreciation and amortization	209	6,494
Total expenses	988	12,513
Net income (loss) from operations	(506)	2,560
Gain (loss) on derivatives	0	1,221
Provision for taxes		129
Net income (loss)	(506)	3,910
Company's share in net income (loss)	(93)	513
Adjustments for REIT basis	0	(36)
Corporate Joint Venture | Gramercy European Property Fund | Continuing Operations
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	(93)	477
Corporate Joint Venture | Strategic Office Partners
Investments in and Advances to Affiliates [Line Items]
Revenues	11,143	5,526
Operating expenses	4,151	1,474
Interest expense	3,113	1,510
Depreciation and amortization	4,823	2,503
Total expenses	12,087	5,487
Net income (loss) from operations	(944)	39
Gain (loss) on derivatives	492	(349)
Provision for taxes		0
Net income (loss)	(452)	(310)
Company's share in net income (loss)	26	(15)
Adjustments for REIT basis	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Extinguishment of Debt	0
Corporate Joint Venture | Strategic Office Partners | Continuing Operations
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	26	(15)
Corporate Joint Venture | Goodman UK JV
Investments in and Advances to Affiliates [Line Items]
Revenues	0	295
Operating expenses	260	302
Interest expense	0	0
Depreciation and amortization	206	375
Total expenses	466	677
Net income (loss) from operations	(466)	(382)
Gain (loss) on derivatives	0	0
Provision for taxes		(8)
Net income (loss)	(466)	(390)
Company's share in net income (loss)	(373)	(312)
Adjustments for REIT basis	(4)	(89)
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Extinguishment of Debt	0
Corporate Joint Venture | Goodman UK JV | Continuing Operations
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	(377)	(401)
Corporate Joint Venture | Other
Investments in and Advances to Affiliates [Line Items]
Revenues	1,994	(1,331)
Operating expenses	106	576
Interest expense	666	641
Depreciation and amortization	333	333
Total expenses	1,105	1,550
Net income (loss) from operations	889	(2,881)
Gain (loss) on derivatives	0	0
Provision for taxes		0
Net income (loss)	889	(2,881)
Company's share in net income (loss)	20	(155)
Adjustments for REIT basis	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Extinguishment of Debt	0
Corporate Joint Venture | Other | Continuing Operations
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	20	$ (155)
Corporate Joint Venture | E-Commerce JV
Investments in and Advances to Affiliates [Line Items]
Revenues	2,165
Operating expenses	583
Interest expense	669
Depreciation and amortization	862
Total expenses	2,114
Net income (loss) from operations	51
Gain (loss) on derivatives	0
Net income (loss)	(1,149)
Company's share in net income (loss)	(520)
Adjustments for REIT basis	18
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Extinguishment of Debt	(1,200)
Corporate Joint Venture | E-Commerce JV | Continuing Operations
Investments in and Advances to Affiliates [Line Items]
Company’s equity in net income (loss) within continuing operations	$ (502)

Debt Obligations (Secured Debt)

Debt Obligations (Secured Debt) (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)Property	Mar. 31, 2017USD ($)Property	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Number of Acquisitions	1
Number of real estate properties in which secured debt repaid		2
Loss on extinguishment of debt | $	$ 0	$ (208)
Mortgages
Debt Instrument [Line Items]
Mortgages transferred		2
Real estate acquisitions | Mortgages
Debt Instrument [Line Items]
Non-recourse debt | $			$ 181,107
Number of Acquisitions		7

Debt Obligations (Schedule of M

Debt Obligations (Schedule of Mortgage Notes Payable) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017Property	Mar. 31, 2018USD ($)Property	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Number of real estate properties in which secured debt repaid | Property	2
Mortgage Notes Payable
Debt Instrument [Line Items]
Outstanding Balance		$ 550,953	$ 554,498
Net deferred financing costs and net debt discount		8,520	9,023
Total mortgage notes payable, net		$ 559,473	563,521
Mortgage Notes Payable | Greenwood, IN
Debt Instrument [Line Items]
Interest Rate		3.59%
Outstanding Balance		$ 7,211	7,257
Mortgage Notes Payable | Greenfield, IN
Debt Instrument [Line Items]
Interest Rate		3.63%
Outstanding Balance		$ 5,828	5,865
Mortgage Notes Payable | Logistics Portfolio - Pool 3
Debt Instrument [Line Items]
Interest Rate		3.96%
Outstanding Balance		$ 43,302	43,302
Number of real estate properties pledged under debt | Property		2
Mortgage Notes Payable | Philadelphia, PA
Debt Instrument [Line Items]
Interest Rate		4.99%
Outstanding Balance		$ 11,842	11,943
Mortgage Notes Payable | Bridgeview, IL
Debt Instrument [Line Items]
Interest Rate		3.90%
Outstanding Balance		$ 5,792	5,838
Mortgage Notes Payable | Spartanburg, SC
Debt Instrument [Line Items]
Interest Rate		3.20%
Outstanding Balance		$ 530	632
Mortgage Notes Payable | Charleston, SC
Debt Instrument [Line Items]
Interest Rate		3.11%
Outstanding Balance		$ 320	457
Mortgage Notes Payable | Lawrence, IN
Debt Instrument [Line Items]
Interest Rate		5.02%
Outstanding Balance		$ 19,896	20,061
Mortgage Notes Payable | Charlotte, NC
Debt Instrument [Line Items]
Interest Rate		3.28%
Outstanding Balance		$ 1,363	1,538
Mortgage Notes Payable | Hawthorne, CA
Debt Instrument [Line Items]
Interest Rate		3.52%
Outstanding Balance		$ 17,042	17,207
Mortgage Notes Payable | Charleston, SC
Debt Instrument [Line Items]
Interest Rate		3.32%
Outstanding Balance		$ 696	758
Mortgage Notes Payable | Charleston, SC
Debt Instrument [Line Items]
Interest Rate		2.97%
Outstanding Balance		$ 684	746
Mortgage Notes Payable | Charleston, SC
Debt Instrument [Line Items]
Interest Rate		3.37%
Outstanding Balance		$ 684	746
Mortgage Notes Payable | Charlotte, NC
Debt Instrument [Line Items]
Interest Rate		3.38%
Outstanding Balance		$ 594	647
Mortgage Notes Payable | Des Plaines, IL
Debt Instrument [Line Items]
Interest Rate		5.54%
Outstanding Balance		$ 2,365	2,385
Mortgage Notes Payable | Waco, TX
Debt Instrument [Line Items]
Interest Rate		4.75%
Outstanding Balance		$ 14,815	14,890
Mortgage Notes Payable | Deerfield, IL
Debt Instrument [Line Items]
Interest Rate		3.71%
Outstanding Balance		$ 10,355	10,447
Mortgage Notes Payable | Winston-Salem, NC
Debt Instrument [Line Items]
Interest Rate		3.41%
Outstanding Balance		$ 3,135	3,354
Mortgage Notes Payable | Winston-Salem, NC
Debt Instrument [Line Items]
Interest Rate		3.42%
Outstanding Balance		$ 1,043	1,114
Mortgage Notes Payable | Logistics Portfolio - Pool 1
Debt Instrument [Line Items]
Interest Rate		4.27%
Outstanding Balance		$ 37,856	38,107
Number of real estate properties pledged under debt | Property		3
Mortgage Notes Payable | CCC Portfolio
Debt Instrument [Line Items]
Interest Rate		4.24%
Outstanding Balance		$ 22,691	22,814
Number of real estate properties pledged under debt | Property		5
Mortgage Notes Payable | Logistics Portfolio - Pool 4
Debt Instrument [Line Items]
Interest Rate		4.36%
Outstanding Balance		$ 79,500	79,500
Number of real estate properties pledged under debt | Property		6
Mortgage Notes Payable | Romeoville, IL
Debt Instrument [Line Items]
Interest Rate		3.80%
Outstanding Balance		$ 24,835	24,951
Mortgage Notes Payable | Romeoville, IL3
Debt Instrument [Line Items]
Interest Rate		9.37%
Outstanding Balance		$ 6,613	6,623
Mortgage Notes Payable | KIK USA Portfolio
Debt Instrument [Line Items]
Interest Rate		4.31%
Outstanding Balance		$ 7,077	7,154
Number of real estate properties pledged under debt | Property		3
Mortgage Notes Payable | Yuma, AZ
Debt Instrument [Line Items]
Interest Rate		5.27%
Outstanding Balance		$ 11,804	11,858
Mortgage Notes Payable | Allentown, PA
Debt Instrument [Line Items]
Interest Rate		5.16%
Outstanding Balance		$ 22,586	22,690
Mortgage Notes Payable | Spartanburg, SC
Debt Instrument [Line Items]
Interest Rate		3.72%
Outstanding Balance		$ 5,447	5,635
Mortgage Notes Payable | Natick, MA
Debt Instrument [Line Items]
Interest Rate		5.21%
Outstanding Balance		$ 31,121	31,224
Mortgage Notes Payable | Natick, MA3
Debt Instrument [Line Items]
Interest Rate		10.38%
Outstanding Balance		$ 3,458	3,469
Mortgage Notes Payable | Maple Grove, MN
Debt Instrument [Line Items]
Interest Rate		3.88%
Outstanding Balance		$ 16,291	16,380
Mortgage Notes Payable | Curtis Bay, MD
Debt Instrument [Line Items]
Interest Rate		4.31%
Outstanding Balance		$ 13,500	13,500
Mortgage Notes Payable | Rialto, CA
Debt Instrument [Line Items]
Interest Rate		3.91%
Outstanding Balance		$ 54,543	54,741
Mortgage Notes Payable | Houston, TX
Debt Instrument [Line Items]
Interest Rate		3.68%
Outstanding Balance		$ 26,000	26,000
Mortgage Notes Payable | Durham, NC
Debt Instrument [Line Items]
Interest Rate		4.02%
Outstanding Balance		$ 3,614	3,631
Mortgage Notes Payable | Charleston, SC
Debt Instrument [Line Items]
Interest Rate		3.80%
Outstanding Balance		$ 5,831	6,001
Mortgage Notes Payable | Hackettstown, NJ
Debt Instrument [Line Items]
Interest Rate		5.49%
Outstanding Balance		$ 9,420	9,455
Mortgage Notes Payable | Hutchins, TX
Debt Instrument [Line Items]
Interest Rate		5.41%
Outstanding Balance		$ 21,269	$ 21,578

Debt Obligations (Unsecured Deb

Debt Obligations (Unsecured Debt) (Narrative) (Details)	3 Months Ended
	Mar. 31, 2018extension	Dec. 31, 2017USD ($)	Oct. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Unsecured Debt | 2015 Revolving Credit Facility - U.S. Dollar Tranche
Debt Instrument [Line Items]
Interest Rate	2.89%
Unsecured Debt | 2015 Revolving Credit Facility - Multicurrency Tranche
Debt Instrument [Line Items]
Interest Rate	1.32%
Unsecured Debt | 3-Year Term Loan
Debt Instrument [Line Items]
Interest Rate	2.91%
Unsecured Debt | 7-Year Term Loan
Debt Instrument [Line Items]
Interest Rate	2.76%
Unsecured Debt | Senior Unsecured Notes
Debt Instrument [Line Items]
Face amount		$ 500,000,000
JPMorgan Chase Bank | 2015 Revolving Credit Facility - U.S. Dollar Tranche
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 1,900,000,000
Line of credit facility, number of extensions | extension	2
JPMorgan Chase Bank | Term Loans | 3-Year Term Loan
Debt Instrument [Line Items]
Face amount				300,000,000
JPMorgan Chase Bank | Term Loans | JPM Term Loan | Federal Funds Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
JPMorgan Chase Bank | Term Loans | JPM Term Loan | LIBOR 30-Day
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
JPMorgan Chase Bank | Revolving Credit Facility | Line of Credit | Unsecured Credit Facility
Debt Instrument [Line Items]
Face amount				850,000,000
JPMorgan Chase Bank | Revolving Credit Facility | Line of Credit | 2015 Revolving Credit Facility - US Dollars Tranche
Debt Instrument [Line Items]
Face amount				750,000,000
JPMorgan Chase Bank | Revolving Credit Facility | Line of Credit | 2015 Revolving Credit Facility - Multicurrency Tranche
Debt Instrument [Line Items]
Face amount				100,000,000
JPMorgan Chase Bank | Revolving Credit Facility | Term Loans | Unsecured Credit Facility
Debt Instrument [Line Items]
Face amount				1,050,000,000
Capital One | Term Loans | 7-Year Term Loan
Debt Instrument [Line Items]
Face amount			$ 400,000	$ 175,000,000
Minimum | Unsecured Debt | Senior Unsecured Notes
Debt Instrument [Line Items]
Interest Rate		3.89%
Minimum | JPMorgan Chase Bank | Term Loans | JPM Term Loan | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.90%
Minimum | JPMorgan Chase Bank | Term Loans | JPM Term Loan | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Minimum | JPMorgan Chase Bank | Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.125%
Minimum | JPMorgan Chase Bank | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.875%
Minimum | JPMorgan Chase Bank | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Maximum | Unsecured Debt | Senior Unsecured Notes
Debt Instrument [Line Items]
Interest Rate		4.97%
Maximum | JPMorgan Chase Bank | Term Loans | JPM Term Loan | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.75%
Maximum | JPMorgan Chase Bank | Term Loans | JPM Term Loan | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.75%
Maximum | JPMorgan Chase Bank | Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.30%
Maximum | JPMorgan Chase Bank | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.55%
Maximum | JPMorgan Chase Bank | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.55%

Debt Obligations (Exchangeable

Debt Obligations (Exchangeable Senior Notes) (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Sep. 30, 2017	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 0	$ 208
Convertible Debt | Exchangeable Senior Notes 3.75%
Debt Instrument [Line Items]
Face amount	$ 115,000
Interest Rate	3.75%
Percent of instrument converted	100.00%
Shares issued in conversion (in shares)	5,258,420
Adjustment to APIC related to extinguishment of exchangeable notes		$ (42,065)

Debt Obligations (Schedule of C

Debt Obligations (Schedule of Credit Facilities and Term Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
2015 Revolving Credit Facility - U.S. Dollar Tranche
Line of Credit Facility [Line Items]
Long-term Debt	$ 292,543
Unsecured Debt
Line of Credit Facility [Line Items]
Outstanding Balance	2,242,543	$ 2,307,162
Unamortized discount and deferred financing costs	(4,872)	(5,063)
Long-term Debt	$ 2,237,671	2,302,099
Unsecured Debt | 2015 Revolving Credit Facility - U.S. Dollar Tranche
Line of Credit Facility [Line Items]
Stated Interest Rate	2.89%
Effective Interest Rate	2.89%
Outstanding Balance	$ 275,000	345,000
Unsecured Debt | 2015 Revolving Credit Facility - Multicurrency Tranche
Line of Credit Facility [Line Items]
Stated Interest Rate	1.32%
Effective Interest Rate	1.32%
Outstanding Balance	$ 17,543	12,162
Unsecured Debt | 3-Year Term Loan
Line of Credit Facility [Line Items]
Stated Interest Rate	2.91%
Effective Interest Rate	2.33%
Outstanding Balance	$ 300,000	300,000
Unsecured Debt | 5-Year Term Loan
Line of Credit Facility [Line Items]
Stated Interest Rate	2.91%
Effective Interest Rate	2.70%
Outstanding Balance	$ 750,000	750,000
Unsecured Debt | 7-Year Term Loan
Line of Credit Facility [Line Items]
Stated Interest Rate	2.76%
Effective Interest Rate	3.00%
Outstanding Balance	$ 400,000	400,000
Unsecured Debt | 2015 Senior Notes Due 2024
Line of Credit Facility [Line Items]
Stated Interest Rate	4.97%
Effective Interest Rate	5.07%
Outstanding Balance	$ 150,000	150,000
Unsecured Debt | 2016 Senior Notes Due 2022
Line of Credit Facility [Line Items]
Stated Interest Rate	3.89%
Effective Interest Rate	4.00%
Outstanding Balance	$ 150,000	150,000
Unsecured Debt | 2016 Senior Notes Due 2025
Line of Credit Facility [Line Items]
Stated Interest Rate	4.26%
Effective Interest Rate	4.38%
Outstanding Balance	$ 100,000	100,000
Unsecured Debt | 2016 Senior Notes Due 2026
Line of Credit Facility [Line Items]
Stated Interest Rate	4.32%
Effective Interest Rate	4.43%
Outstanding Balance	$ 100,000	$ 100,000

Debt Obligations (Schedule of57

Debt Obligations (Schedule of Maturities of Long-term Debt) (Details) $ in Thousands	Mar. 31, 2018USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
Above market interest	$ 3,648
Long-term Debt, Interest Payments, Fiscal Year Maturity [Abstract]
April1 to December 31, 2018, interest	82,144
2019, interest	97,025
2020, interest	87,135
2021, interest	57,199
2022, interest	53,364
Thereafter, interest	64,772
Interest payments, total	445,287
Long-term Debt and Interest, Fiscal Year Maturity [Abstract]
April 1 to December 31, 2018, total	148,743
2019, total	427,475
2020, total	442,512
2021, total	826,455
2022, total	345,293
Thereafter, total	1,044,657
Net premium, total	3,238,783
2015 Revolving Credit Facility
Long-term Debt, Fiscal Year Maturity [Abstract]
April 1 to December 31, 2018	0
2,019	0
2,020	292,543
2,021	0
2,022	0
Thereafter	0
Above market interest	0
Long-term Debt	292,543
Senior Unsecured Notes
Long-term Debt, Fiscal Year Maturity [Abstract]
April 1 to December 31, 2018	0
2,019	0
2,020	0
2,021	0
2,022	150,000
Thereafter	350,000
Above market interest	0
Long-term Debt	500,000
Term Loans
Long-term Debt, Fiscal Year Maturity [Abstract]
April 1 to December 31, 2018	0
2,019	300,000
2,020	0
2,021	750,000
2,022	0
Thereafter	400,000
Above market interest	0
Long-term Debt	1,450,000
Mortgage Notes Payable
Long-term Debt, Fiscal Year Maturity [Abstract]
April 1 to December 31, 2018	66,599
2,019	30,450
2,020	62,834
2,021	19,256
2,022	141,929
Thereafter	229,885
Above market interest	0
Long-term Debt	$ 550,953

Transactions with Trustee Rel58

Transactions with Trustee Related Entities and Related Parties (Narrative) (Details) € in Thousands, $ in Thousands	Mar. 31, 2018USD ($)director	Mar. 31, 2018EUR (€)director	Dec. 31, 2017USD ($)
Related Party Transaction [Line Items]
Investments in joint ventures | $	$ 99,113		$ 70,214
Chief Executive Officer | Gramercy Europe
Related Party Transaction [Line Items]
Investments in joint ventures	1,388	€ 1,250
Managing Directors | Gramercy Europe
Related Party Transaction [Line Items]
Investments in joint ventures	$ 1,388	€ 1,250
Gramercy Europe Asset
Related Party Transaction [Line Items]
Number of managing directors | director	2	2

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) $ in Thousands	Mar. 31, 2018USD ($)Property	Dec. 31, 2017USD ($)Property
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Properties impaired | Property	0	7
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset value	$ 50,557	$ 116,011
Real estate investments | Fair Value | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset value		$ 87,996

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Carrying Value and Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Retained CDO Bonds
Financial assets:
Investments	$ 5,800
Carrying Value
Financial assets:
Loan investments	22,437	$ 22,154
Long-term debt:
2015 Revolving Credit Facility	292,543	357,162
Mortgage notes payable	559,473	563,521
Carrying Value | 3-Year Term Loan
Long-term debt:
Term loans	300,000	300,000
Carrying Value | 5-Year Term Loan
Long-term debt:
Term loans	750,000	750,000
Carrying Value | 7-Year Term Loan
Long-term debt:
Term loans	398,241	398,152
Carrying Value | Senior Unsecured Notes
Long-term debt:
Senior notes	496,887	496,785
Carrying Value | Interest rate swaps
Financial assets:
Interest rate swaps	41,888	19,668
Financial liabilities:
Interest rate swaps	13	173
Carrying Value | Retained CDO Bonds
Financial assets:
Investments	5,800	5,527
Carrying Value | Investment in CBRE Strategic Partners Asia
Financial assets:
Investments	2,869	2,820
Carrying Value | Real estate investments
Financial assets:
Investments	0	87,996
Fair Value
Financial assets:
Loan investments	20,990	21,362
Long-term debt:
2015 Revolving Credit Facility	292,492	357,369
Mortgage notes payable	565,329	573,826
Fair Value | 3-Year Term Loan
Long-term debt:
Term loans	300,090	300,091
Fair Value | 5-Year Term Loan
Long-term debt:
Term loans	750,653	750,678
Fair Value | 7-Year Term Loan
Long-term debt:
Term loans	400,020	400,010
Fair Value | Senior Unsecured Notes
Long-term debt:
Senior notes	502,349	513,229
Fair Value | Interest rate swaps
Financial assets:
Interest rate swaps	41,888	19,668
Financial liabilities:
Interest rate swaps	13	173
Fair Value | Retained CDO Bonds
Financial assets:
Investments	5,800	5,527
Fair Value | Investment in CBRE Strategic Partners Asia
Financial assets:
Investments	2,869	2,820
Fair Value | Real estate investments
Financial assets:
Investments	$ 0	$ 87,996

Fair Value Measurements (Sche61

Fair Value Measurements (Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis) (Details) - Fair Value - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	$ 50,557	$ 116,011
Financial Liabilities:	(13)	(173)
Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Liabilities:	(13)	(173)
Retained CDO Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	5,800	5,527
Marketable securities | Real estate investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:		87,996
Marketable securities | Investment in CBRE Strategic Partners Asia
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	2,869	2,820
Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	41,888	19,668
Level I
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Financial Liabilities:	0	0
Level I | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Liabilities:	0	0
Level I | Retained CDO Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level I | Marketable securities | Real estate investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:		0
Level I | Marketable securities | Investment in CBRE Strategic Partners Asia
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level I | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level II
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Financial Liabilities:	0	0
Level II | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Liabilities:	0	0
Level II | Retained CDO Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level II | Marketable securities | Real estate investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:		0
Level II | Marketable securities | Investment in CBRE Strategic Partners Asia
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level II | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	0	0
Level III
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	50,557	116,011
Financial Liabilities:	(13)	(173)
Level III | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Liabilities:	(13)	(173)
Level III | Retained CDO Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	5,800	5,527
Level III | Marketable securities | Real estate investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:		87,996
Level III | Marketable securities | Investment in CBRE Strategic Partners Asia
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	2,869	2,820
Level III | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets:	$ 41,888	$ 19,668

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value, Assets and Liabilities Measured on Recurring Basis, Valuation Techniques) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap liabilities fair value	$ 13	$ 173
CBRE Strategic Partners Asia
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value	$ 2,869
Discount rate	20.00%
Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Fair Value	$ 41,875
Interest rate swaps | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap liabilities fair value	$ 13	173
Minimum | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	1.10%
Maximum | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	1.90%
Non-investment grade, subordinate CDO bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value	$ 5,800
Discount rate	19.00%
Non-investment grade, subordinate CDO bonds | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value	$ 5,800	$ 5,527

Fair Value Measurements (Fair63

Fair Value Measurements (Fair Value, Assets (Liabilities) Measured on Recurring Basis, Unobservable Input Reconciliation) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 27,842
Amortization of discounts or premiums	651
Adjustments to fair value:
Unrealized loss in other comprehensive income from fair value adjustment	(48)
Total gain on fair value adjustments	49
Ending balance	50,544
Adjustments To Fair Value, Assets (Liabilities) [Abstract]
Unrealized gain on derivatives	22,050
Interest rate swaps
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Amortization of discounts or premiums	330
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	19,495
Adjustments To Fair Value, Assets (Liabilities) [Abstract]
Unrealized gain on derivatives	22,050
Ending balance	41,875
Investment in CBRE Strategic Partners Asia
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	2,820
Adjustments to fair value:
Total gain on fair value adjustments	49
Ending balance	2,869
Retained CDO Bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	5,527
Amortization of discounts or premiums	321
Adjustments to fair value:
Unrealized loss in other comprehensive income from fair value adjustment	(48)
Ending balance	$ 5,800

Derivatives and Non-Derivativ64

Derivatives and Non-Derivative Hedging Instruments (Schedule of Derivative Instruments) (Details) - Not Designated as Hedging Instrument £ in Thousands, $ in Thousands	Mar. 31, 2018USD ($)	Mar. 31, 2018GBP (£)
Derivative [Line Items]
Fair Value	$ 41,875
Interest Rate Swap Strike Rate 4.55%
Derivative [Line Items]
Notional Value	$ 14,815
Strike Rate	4.55%	4.55%
Fair Value	$ (13)
Interest Rate Swap Strike Rate 1.22%
Derivative [Line Items]
Notional Value	$ 100,000
Strike Rate	1.22%	1.22%
Fair Value	$ 615
Interest Rate Swap Strike Rate 1.23%
Derivative [Line Items]
Notional Value	$ 100,000
Strike Rate	1.23%	1.23%
Fair Value	$ 612
Interest Rate Swap Strike Rate 1.24%
Derivative [Line Items]
Notional Value	$ 100,000
Strike Rate	1.24%	1.24%
Fair Value	$ 604
Interest Rate Swap Strike Rate 1.60%
Derivative [Line Items]
Notional Value	$ 750,000
Strike Rate	1.60%	1.60%
Fair Value	$ 17,010
Interest Rate Swap Strike Rate 1.82%
Derivative [Line Items]
Notional Value	$ 175,000
Strike Rate	1.82%	1.82%
Fair Value	$ 5,660
Interest Rate Swap Strike Rate 1.95%
Derivative [Line Items]
Notional Value	$ 60,000
Strike Rate	1.95%	1.95%
Fair Value	$ 1,599
Interest Rate Swap Strike Rate 2.01%
Derivative [Line Items]
Notional Value	$ 40,000
Strike Rate	2.01%	2.01%
Fair Value	$ 953
Interest Rate Swap Strike Rate 1.96%
Derivative [Line Items]
Notional Value	$ 39,500
Strike Rate	1.96%	1.96%
Fair Value	$ 1,016
Interest Rate Swap Strike Rate 1.96%
Derivative [Line Items]
Notional Value	$ 31,500
Strike Rate	1.96%	1.96%
Fair Value	$ 809
Interest Rate Swap Strike Rate 2.00%
Derivative [Line Items]
Notional Value	$ 31,500
Strike Rate	2.00%	2.00%
Fair Value	$ 765
Interest Rate Swap Strike Rate 1.95%
Derivative [Line Items]
Notional Value	$ 22,500
Strike Rate	1.95%	1.95%
Fair Value	$ 593
Forward Starting Swap
Derivative [Line Items]
Notional Value	$ 250,000
Strike Rate	2.23%	2.23%
Fair Value	$ 11,652
Net Investment Hedge in GBP-denominated investments
Derivative [Line Items]
Notional Value | £		£ 9,000
Fair Value	0
Net Investment Hedge in EUR-denominated investments
Derivative [Line Items]
Notional Value | £		£ 4,000
Fair Value	$ 0

Derivatives and Non-Derivativ65

Derivatives and Non-Derivative Hedging Instruments (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivative [Line Items]
Cumulative effect of accounting changes			$ 663
Interest expense	$ 25,492	$ 23,056
Interest rate swaps
Derivative [Line Items]
Derivative asset, fair value	41,888
Net liability of derivative	(13)
Amounts reclassified from OCI	(7,947)
Interest expense to be recognized	1,295
Remaining AOCI balance related to swap to be reclassified in the next twelve months	1,087
Net Investment Hedge in GBP-denominated Investments
Derivative [Line Items]
Net loss on hedge ineffectiveness	$ (459)	$ (923)
Accumulated Other Comprehensive Income (Loss)
Derivative [Line Items]
Cumulative effect of accounting changes			$ 103

Derivatives and Non-Derivativ66

Derivatives and Non-Derivative Hedging Instruments (Gain Recognized On Interest Rate Swaps) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivative [Line Items]
Gain reclassified from accumulated other comprehensive income (loss) into interest expense	$ 268	$ 268
Cumulative effect of accounting changes			$ 663
Interest Expense
Derivative [Line Items]
Gain recognized in accumulated other comprehensive income (loss)		0
Interest Expense | Interest rate swaps
Derivative [Line Items]
Gain recognized in accumulated other comprehensive income (loss)	22,153
Gain reclassified from accumulated other comprehensive income (loss) into interest expense	268	268
Gain recognized in interest expense (ineffective portion)	0	46
Total recognized in interest expense on statements of operations	$ 268	$ 314
Accounting Standards Update 2017-02
Derivative [Line Items]
Cumulative effect of accounting changes			$ 103

Shareholders' Equity (Deficit67

Shareholders' Equity (Deficit) of the Company (ESPP, DRIP, Share Repurchase and ATM Equity Offering Program Narrative) (Details)	1 Months Ended				3 Months Ended
	Sep. 30, 2017shares	Dec. 31, 2016	Jul. 31, 2016USD ($)	Jun. 30, 2016shares	Mar. 31, 2018$ / sharesshares	Mar. 31, 2017$ / shares	Dec. 31, 2017$ / sharesshares
Class of Stock [Line Items]
Capital units, authorized (in shares)					500,000,000		500,000,000
Common stock, par value (in usd per share) | $ / shares					$ 0.01		$ 0.01
Capital stock, par value (in usd per share) | $ / shares							$ 0.01
Common stock, shares authorized (in shares)					490,000,000		490,000,000
Preferred stock, shares authorized (in shares)					10,000,000		10,000,000
Preferred stock, shares outstanding (in shares)					3,500,000
Dividends declared (in usd per share) | $ / shares						$ 0.375
Stock split conversion ratio		0.3333
ESPP shares authorized (in shares)					250,000
ESPP purchase discount percent					90.00%
ESPP shares held (in shares)					0
Shares registered for DRIP (in shares)				3,333,333
Dividend reinvestment program proceeds (in shares)					1,811
Shares available for issuance under DRIP (in shares)					3,323,962
At-the-market offering | $			$ 375,000,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)					3,500,000		3,500,000
Preferred stock, shares outstanding (in shares)					3,500,000		3,500,000
Preferred stock, shares issued (in shares)					3,500,000		3,500,000
Exchangeable Senior Notes 3.75% | Convertible Debt
Class of Stock [Line Items]
Shares issued in conversion (in shares)	5,258,420
Percent of instrument converted	100.00%
GPT Operating Partnership LP
Class of Stock [Line Items]
Partnership units (in units)					160,782,765

Shareholders' Equity (Deficit68

Shareholders' Equity (Deficit) of the Company (Dividends Paid) (Details)	3 Months Ended
	Mar. 31, 2017$ / shares
Equity [Abstract]
Dividends declared (in usd per share)	$ 0.375

Shareholders' Equity (Deficit69

Shareholders' Equity (Deficit) of the Company (Preferred Stock) (Narrative) (Details) - $ / shares	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)	3,500,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)	3,500,000	3,500,000
Preferred stock, redemption price per share (in usd per share)	$ 25
7.125% Series A Preferred Stock
Class of Stock [Line Items]
Dividend rate on preferred stock	7.125%
Preferred stock, dividend rate (in usd per share)	$ 1.78125

Shareholders' Equity (Deficit70

Shareholders' Equity (Deficit) of the Company (Equity Plan Summaries and Earnings Per Share) (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Sep. 30, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Outside Interests in Operating Partnership
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities (in shares)		5,040,730	620,586
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted shares outstanding (in shares)		316,183		347,676
2016 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)		2,634,080
Grants in period (in shares)		1,129,130
Shares vesting percentage		67.20%
2016 Equity Incentive Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 541	$ 817
Share based compensation expense, not yet recognized		$ 4,757
Share based compensation expense, not yet recognized, period of recognition		26 months
Outperformance Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 1,138	$ 1,056
Share based compensation expense, not yet recognized		$ 10,188
Share based compensation expense, not yet recognized, period of recognition		35 months
Exchangeable Senior Notes 3.75% | Convertible Debt
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of instrument converted	100.00%

Shareholders' Equity (Deficit71

Shareholders' Equity (Deficit) of the Company (Schedule of Calculation of Numerator and Denominator in Earnings Per Share) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator - Income (loss)
Net income (loss) from continuing operations	$ 11,609	$ (8,072)
Net loss from discontinued operations	0	(24)
Net income (loss) before net gain on disposals	11,609	(8,096)
Net gain on disposals	16,255	17,377
Net income	27,864	9,281
Net income attributable to noncontrolling interest	(802)	(154)
Less: Nonforfeitable dividends allocated to participating shareholders	(203)	(276)
Less: Preferred share dividends	(1,559)	(1,559)
Net income available to common shares outstanding	$ 25,300	$ 7,292
Denominator – Weighted average shares
Weighted average basic shares outstanding (in shares)	160,408,136	140,907,399
Effect of dilutive securities
Unvested non-participating share based payment awards (in shares)	0	71,848
Option (in shares)	8,764	15,576
Exchangeable Senior Notes (in shares)	0	880,796
Diluted shares (in shares)	160,416,900	141,875,619

Shareholders' Equity (Deficit72

Shareholders' Equity (Deficit) of the Company (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Net unrealized gain on derivative securities	$ 37,680	$ 15,630
Net unrealized gain on debt instruments	369	417
Foreign currency translation adjustments:
Net gain on non-derivative net investment hedges	(162)	297
Other foreign currency translation adjustments	(4,757)	(5,734)
Reclassification of swap gain into interest expense	2,434	2,166
Cumulative effect of accounting change	103	0
Total accumulated other comprehensive income	35,667	$ 12,776
Write-off on non-derivative net investment hedge	$ 1,851

Partners' Capital of the Oper73

Partners' Capital of the Operating Partnership (Narrative) (Details) - GPT Operating Partnership LP	Mar. 31, 2018shares
Limited Partners' Capital Account [Line Items]
Partnership units (in units)	160,782,765
Ownership interest in Operating Partnership	96.75%
Ownership percentage by noncontrolling owners	3.25%
Noncontrolling Interest
Limited Partners' Capital Account [Line Items]
Partnership units (in units)	5,388,995

Partners' Capital of the Oper74

Partners' Capital of the Operating Partnership (Calculation of Earnings Per Share) (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Dec. 31, 2016	Mar. 31, 2018USD ($)shares	Mar. 31, 2017USD ($)shares
Numerator - Income (loss)
Net income (loss) from continuing operations		$ 11,609	$ (8,072)
Net loss from discontinued operations		0	(24)
Net income (loss) before net gain on disposals		11,609	(8,096)
Net gain on disposals		16,255	17,377
Net income		27,864	9,281
Less: Nonforfeitable dividends allocated to participating unitholders		(203)	(276)
Less: Preferred unit distributions		$ (1,559)	$ (1,559)
Effect of dilutive securities
Unvested non-participating unit based payment awards (in units) | shares		0	71,848
Option (in units) | shares		8,764	15,576
Exchangeable Senior Notes (in units) | shares		0	880,796
Stock split conversion ratio	0.3333
GPT Operating Partnership LP
Numerator - Income (loss)
Net income (loss) from continuing operations		$ 11,609	$ (8,072)
Net loss from discontinued operations		0	(24)
Net income (loss) before net gain on disposals		11,609	(8,096)
Net gain on disposals		16,255	17,377
Net income		27,864	9,281
Less: Net gain attributable to noncontrolling interest in other partnerships		0	(120)
Less: Nonforfeitable dividends allocated to participating unitholders		(203)	(276)
Less: Preferred unit distributions		(1,559)	(1,559)
Net income available to common unitholders		$ 26,102	$ 7,326
Denominator – Weighted average shares
Weighted average basic units outstanding (in units) | shares		165,448,866	141,527,985
Effect of dilutive securities
Unvested non-participating unit based payment awards (in units) | shares		0	71,848
Option (in units) | shares		8,764	15,576
Exchangeable Senior Notes (in units) | shares		0	880,796
Diluted shares (in shares) | shares		165,457,630	142,496,205

Noncontrolling Interests (Narra

Noncontrolling Interests (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)Propertyshares	Mar. 31, 2017shares	Dec. 31, 2017USD ($)shares
Noncontrolling Interest [Line Items]
Capital shares reserved for future issuance (in shares)	4,729,480
Noncontrolling interest in operating partnership (in usd) | $	$ 137,800		$ 113,530
Long-term Incentive Plan Units
Noncontrolling Interest [Line Items]
Capital shares reserved for future issuance (in shares)	659,515
GPT Operating Partnership LP
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners	3.25%
Limited partners' capital, units outstanding	159,124,705		159,035,964
Noncontrolling interest in operating partnership (in usd) | $	$ 137,800		$ 113,530
GPT Operating Partnership LP | Long-term Incentive Plan Units
Noncontrolling Interest [Line Items]
Shares vested (in shares)	659,515
Limited Partner | GPT Operating Partnership LP
Noncontrolling Interest [Line Items]
Limited partners' capital, units outstanding	4,729,480
Shares converted	6,038	134,607
Noncontrolling interest in operating partnership (in usd) | $	$ 137,800		$ 113,530
E-Commerce JV | GPT Operating Partnership LP
Noncontrolling Interest [Line Items]
Acquisitions (in units)	996,098
Number of operating properties | Property	2

Noncontrolling Interests (Nonco

Noncontrolling Interests (Noncontrolling Interest in the Operating Partnership) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 113,530
Balance at end of period	137,800
GPT Operating Partnership LP
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	113,530
Balance at end of period	137,800
Limited Partner | GPT Operating Partnership LP
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	113,530
Issuance of noncontrolling interests in the Operating Partnership	25,142
Redemption of noncontrolling interests in the Operating Partnership	(130)
Net income attribution	802
Fair value adjustments	232
Dividends	(1,776)
Balance at end of period	$ 137,800

Commitments and Contingencies77

Commitments and Contingencies (Narrative) (Details) € in Thousands, $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Nov. 30, 2017USD ($)Property	Mar. 31, 2018USD ($)Propertyshares	Mar. 31, 2018EUR (€)Propertyshares	Dec. 31, 2017Property	Mar. 31, 2018EUR (€)Property	Oct. 31, 2017USD ($)	Oct. 31, 2017EUR (€)
Commitments And Contingencies [Line Items]
Contributions to unconsolidated equity investments		$ 28,731
Number of Acquisitions | Property		1	1
Round Rock
Commitments And Contingencies [Line Items]
Commitment amount		$ 59,104
Gramercy European Property Fund III
Commitments And Contingencies [Line Items]
Aggregate cost						$ 323,359	€ 262,622
Payments to investments		2,460	€ 1,977
Gramercy European Property Fund III | Parent Company
Commitments And Contingencies [Line Items]
Aggregate cost		64,257			€ 52,187
E-Commerce JV
Commitments And Contingencies [Line Items]
Commitment amount		110,000
Contributions to unconsolidated equity investments		30,206
Cash contributions to equity method investment	$ 30,000	1,130
Number of Acquisitions | Property	6			6
Strategic Office Partners
Commitments And Contingencies [Line Items]
Commitment amount		400,000
Investment in unconsolidated equity investment		29,477
Strategic Office Partners | Parent Company
Commitments And Contingencies [Line Items]
Commitment amount		$ 100,000
Build-to-suit Property | Round Rock
Commitments And Contingencies [Line Items]
Properties obligated to build | Property		1			1
GPT Operating Partnership LP | E-Commerce JV
Commitments And Contingencies [Line Items]
Acquisitions (in units) | shares		996,098	996,098

Commitments and Contingencies78

Commitments and Contingencies (Schedule of Future Minimum Rental Payments) (Details) $ in Thousands	Mar. 31, 2018USD ($)
Ground Leases - Operating
April 1 to December 31, 2018, operating	$ 1,888
2019, operating	2,593
2020, operating	2,596
2021, operating	2,567
2022, operating	2,598
Thereafter, operating	73,175
Total minimum rent expense, operating	85,417
Ground Leases - Capital
April 1 to December 31, 2018, capital	1
2019, capital	0
2020, capital	0
2021, capital	0
2022, capital	0
Thereafter, capital	329
Total minimum rent expense, capital	330
Total
April 1 to December 31, 2018	1,889
2,019	2,593
2,020	2,596
2,021	2,567
2,022	2,598
Thereafter	73,504
Total	$ 85,747

Supplemental Cash Flow Inform79

Supplemental Cash Flow Information (Non-Cash Activities Recognized in Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Interest paid	$ 19,320	$ 17,447
Income taxes paid	60	71
Proceeds from 1031 exchanges from sale of real estate	5	23,219
Use of funds from 1031 exchanges for acquisitions of real estate	(5)	(23,218)
Non-cash activity:
Fair value adjustment to noncontrolling interest in the Operating Partnership	232	(296)
Debt assumed in acquisition of real estate	0	3,680
Debt transferred in disposition of real estate	0	(10,456)
Non-cash acquisition of consolidated VIE	0	24,930
Dividend reinvestment plan proceeds	46	81
Redemption of units of noncontrolling interest in the Operating Partnership for common shares	(130)	(2,164)
Contributions to unconsolidated equity investments for units of noncontrolling interests in the operating partnership	$ 25,141	$ 0

Subsequent Events (Narrative) (

Subsequent Events (Narrative) (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2018USD ($)Property$ / sharesshares	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)$ / shares
Subsequent Event [Line Items]
Dividends declared (in usd per share) | $ / shares			$ 0.375
Proceeds from sale of land | $		$ 111,012	$ 51,683
Subsequent Event
Subsequent Event [Line Items]
Dividends declared (in usd per share) | $ / shares	$ 0.375
Proceeds from sale of land | $	$ 975
7.125% Series A Preferred Stock
Subsequent Event [Line Items]
Dividend rate on preferred stock		7.125%
7.125% Series A Preferred Stock | Subsequent Event
Subsequent Event [Line Items]
Dividend rate on preferred stock	7.125%
Dividends declared (in usd per share) | $ / shares	$ 0.44531
E-Commerce JV | Subsequent Event
Subsequent Event [Line Items]
Acquisitions (in units) | shares	570,863
Acquisitions, value | $	$ 16,663
Number of operating properties | Property	2

Uncategorized Items - gpt-20180

Label	Element	Value
Gramercy European Property Fund (excluding legacy Goodman Europe Joint Venture) [Member] | Corporate Joint Venture [Member]
Equity Method Investment Summarized Financial Information Interest Expense	gpt_EquityMethodInvestmentSummarizedFinancialInformationInterestExpense	$ 1,474,000
Equity Method Investment, Summarized Financial Information, Income Tax Expense (Benefit)	gpt_EquityMethodInvestmentSummarizedFinancialInformationIncomeTaxExpenseBenefit	(146,000)
Income Loss From Equity Method Investments Prior To Adjustments For Reit Basis	gpt_IncomeLossFromEquityMethodInvestmentsPriorToAdjustmentsForReitBasis	446,000
Equity Method Investment, Summarized Financial Information, Operating Expenses	gpt_EquityMethodInvestmentSummarizedFinancialInformationOperatingExpenses	2,951,000
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	2,587,000
Equity Method Investment, Summarized Financial Information, Revenue	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationRevenue	10,118,000
Equity Method Investment Summarized Financial Information Depreciation and Amortization	gpt_EquityMethodInvestmentSummarizedFinancialInformationDepreciationandAmortization	4,473,000
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss)	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationGrossProfitLoss	1,220,000
Equity Method Investment Summarized Financial Information Expenses	gpt_EquityMethodInvestmentSummarizedFinancialInformationExpenses	8,898,000
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Derivatives	gpt_EquityMethodInvestmentSummarizedFinancialInformationGainLossonDerivatives	1,221,000
Income (Loss) from Equity Method Investments, Adjustments for REIT Basis	gpt_IncomeLossfromEquityMethodInvestmentsAdjustmentsforREITBasis	0
Gramercy European Property Fund (excluding legacy Goodman Europe Joint Venture) [Member] | Continuing Operations [Member] | Corporate Joint Venture [Member]
Income (Loss) from Equity Method Investments	us-gaap_IncomeLossFromEquityMethodInvestments	446,000
Goodman Europe Joint Venture [Member] | Corporate Joint Venture [Member]
Equity Method Investment Summarized Financial Information Interest Expense	gpt_EquityMethodInvestmentSummarizedFinancialInformationInterestExpense	672,000
Equity Method Investment, Summarized Financial Information, Income Tax Expense (Benefit)	gpt_EquityMethodInvestmentSummarizedFinancialInformationIncomeTaxExpenseBenefit	17,000
Income Loss From Equity Method Investments Prior To Adjustments For Reit Basis	gpt_IncomeLossFromEquityMethodInvestmentsPriorToAdjustmentsForReitBasis	67,000
Equity Method Investment, Summarized Financial Information, Operating Expenses	gpt_EquityMethodInvestmentSummarizedFinancialInformationOperatingExpenses	922,000
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	1,323,000
Equity Method Investment, Summarized Financial Information, Revenue	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationRevenue	4,955,000
Equity Method Investment Summarized Financial Information Depreciation and Amortization	gpt_EquityMethodInvestmentSummarizedFinancialInformationDepreciationandAmortization	2,021,000
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss)	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationGrossProfitLoss	1,340,000
Equity Method Investment Summarized Financial Information Expenses	gpt_EquityMethodInvestmentSummarizedFinancialInformationExpenses	3,615,000
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Derivatives	gpt_EquityMethodInvestmentSummarizedFinancialInformationGainLossonDerivatives	0
Income (Loss) from Equity Method Investments, Adjustments for REIT Basis	gpt_IncomeLossfromEquityMethodInvestmentsAdjustmentsforREITBasis	36,000
Goodman Europe Joint Venture [Member] | Continuing Operations [Member] | Corporate Joint Venture [Member]
Income (Loss) from Equity Method Investments	us-gaap_IncomeLossFromEquityMethodInvestments	$ 31,000