Kilroy Realty (KRC) 10-K 15 Feb 17 2016 Q4 Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 31, 2016	Feb. 10, 2017	Jun. 30, 2016
Entity Information [Line Items]
Entity Registrant Name	KILROY REALTY CORP
Entity Central Index Key	1,025,996
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q4
Amendment Flag	false
Entity Common Stock, Shares Outstanding		97,774,137
Entity Public Float			$ 6,104,537,915
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Kilroy Realty, L.P. [Member]
Entity Information [Line Items]
Entity Registrant Name	Kilroy Realty, L.P.
Entity Central Index Key	1,493,976
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q4
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
REAL ESTATE ASSETS
Land and improvements	$ 1,108,971	$ 875,794
Buildings and improvements	4,938,250	4,091,012
Undeveloped land and construction in progress	1,013,533	1,361,340
Total real estate assets held for investment	7,060,754	6,328,146
Accumulated depreciation and amortization	(1,139,853)	(994,241)
Total real estate assets held for investment, net	5,920,901	5,333,905
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET	9,417	117,666
CASH AND CASH EQUIVALENTS	193,418	56,508
RESTRICTED CASH	56,711	696
MARKETABLE SECURITIES	14,773	12,882
CURRENT RECEIVABLES, NET	13,460	11,153
DEFERRED RENT RECEIVABLES, NET	218,977	189,704
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET	208,368	176,683
PREPAID EXPENSES AND OTHER ASSETS, NET	70,608	27,233
TOTAL ASSETS	6,706,633	5,926,430
LIABILITIES:
Secured debt, net	472,772	380,835
Unsecured debt, net	1,847,351	1,844,634
Accounts payable, accrued expenses and other liabilities	202,391	246,323
Accrued dividends and distributions	222,306	34,992
Deferred revenue and acquisition-related intangible liabilities, net	150,360	128,156
Rents received in advance and tenant security deposits	52,080	49,361
Liabilities and deferred revenue of real estate assets held for sale	56	7,543
Total liabilities	2,947,316	2,691,844
COMMITMENTS AND CONTINGENCIES
Preferred Stock, $.01 par value, 30,000,000 shares authorized,
Common stock, $.01 par value, 150,000,000 shares authorized, 93,219,439 and 92,258,690 shares issued and outstanding, respectively	932	923
Additional paid-in capital	3,457,649	3,047,894
Distributions in excess of earnings	(107,997)	(70,262)
Total stockholders’ equity	3,542,995	3,170,966
Noncontrolling Interests:
Common units of the Operating Partnership	85,590	57,100
Noncontrolling interests in consolidated property partnerships	130,732	6,520
Total noncontrolling interests	216,322	63,620
Total equity	3,759,317	3,234,586
TOTAL LIABILITIES AND EQUITY	6,706,633	5,926,430
Series G Preferred Stock [Member]
Preferred Stock, $.01 par value, 30,000,000 shares authorized,
Redeemable Preferred stock	96,155	96,155
Series H Preferred Stock [Member]
Preferred Stock, $.01 par value, 30,000,000 shares authorized,
Redeemable Preferred stock	$ 96,256	$ 96,256

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity Consolidated Carrying Amounts, Real Estate Assets, net	$ 187,254	$ 211,755
Common stock, shares outstanding	93,219,439	92,258,690
Common stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	93,219,439	92,258,690
Common stock, shares outstanding	93,219,439	92,258,690
Preferred Stock [Member]
Preferred stock, shares authorized	30,000,000	30,000,000
Preferred stock, par value	$ 0.01	$ 0.01
Series G Preferred Stock [Member]
Preferred stock, shares authorized	4,600,000	4,600,000
Preferred units, issued		4,000,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares outstanding		4,000,000
Preferred stock dividend rate (percentage)	6.875%	6.875%
Preferred stock liquidation preference	$ 100,000	$ 100,000
Series H Preferred Stock [Member]
Preferred stock, shares authorized	4,000,000	4,000,000
Preferred units, issued		4,000,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares outstanding		4,000,000
Preferred stock dividend rate (percentage)	6.375%	6.375%
Preferred stock liquidation preference	$ 100,000	$ 100,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
REVENUES:
Rental income	$ 574,413	$ 525,355	$ 466,328
Tenant reimbursements	61,079	53,774	46,717
Other property income	7,080	2,146	8,680
Total revenues	642,572	581,275	521,725
EXPENSES:
Property expenses	113,932	105,378	100,514
Real estate taxes	55,206	50,223	45,197
Provision for bad debts	0	545	58
Ground leases	3,439	3,096	3,075
General and administrative expenses	57,029	48,265	46,152
Acquisition-related expenses	1,902	497	1,479
Depreciation and amortization	217,234	204,294	202,417
Total expenses	448,742	412,298	398,892
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (losses)	1,764	243	561
Interest expense	(55,803)	(57,682)	(67,571)
Total other (expenses) income	(54,039)	(57,439)	(67,010)
INCOME FROM CONTINUING OPERATIONS BEFORE GAINS ON SALES OF REAL ESTATE	139,791	111,538	55,823
Net (loss) gain on sales of land	(295)	17,116	3,490
Gains on sales of depreciable operating properties	164,302	109,950	0
INCOME FROM CONTINUING OPERATIONS	303,798	238,604	59,313
DISCONTINUED OPERATIONS
Income from discontinued operations	0	0	2,573
Net gain on dispositions of discontinued operations	0	0	121,922
Total income from discontinued operations	0	0	124,495
NET INCOME	303,798	238,604	183,808
Net income attributable to noncontrolling common units of the Operating Partnership	(6,635)	(4,339)	(3,589)
Net income attributable to noncontrolling interests in consolidated property partnerships	3,375	184	0
Total income attributable to noncontrolling interests	(10,010)	(4,523)	(3,589)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION	293,788	234,081	180,219
PREFERRED DISTRIBUTIONS AND DIVIDENDS:
PREFERRED DIVIDENDS	(13,250)	(13,250)	(13,250)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 280,538	$ 220,831	$ 166,969
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	$ 3	$ 2.44	$ 0.52
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	2.97	2.42	0.51
Net income available to common stockholders per share-basic	3	2.44	1.99
Net income available to common stockholders per share-diluted	$ 2.97	$ 2.42	$ 1.95
Weighted average shares of common stock outstanding – basic	92,342,483	89,854,096	83,090,235
Weighted average shares of common stock outstanding – diluted	93,023,034	90,395,775	84,967,720

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Total Stockholders' Equity	Preferred Stock [Member]	Common stock [Member]	Common Stock Additional Paid-in Capital [Member]	Common Stock Distributions in Excess of Earnings [Member]	Noncontrolling Interests - Common Units of the Operating Partnership [Member]
Beginning Balance at Dec. 31, 2013	$ 2,516,160	$ 2,461,312	$ 192,411	$ 822	$ 2,478,975	$ (210,896)	$ 54,848
Beginning Balance, shares at Dec. 31, 2013				82,153,944
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	183,808	180,219				180,219	3,589
Issuance of common stock	123,860	123,860		$ 20	123,840
Issuance of common stock, shares				1,950,599
Issuance of share-based compensation awards	1,692	1,692			1,692
Issuance of share-based compensation awards, shares				0
Non-cash amortization of share-based compensation	14,471	14,471			14,471
Exercise of stock options	(21,092)	(21,092)		$ (5)	(21,087)
Exercise of stock options, shares				495,000
Repurchase of common stock and restricted stock units	(3,533)	(3,533)			(3,533)
Repurchase of common stock and restricted stock units, shares				(58,045)
Settlement of restricted stock units for shares of common stock	(1)	(1)		$ 0	(1)
Settlement of restricted stock units for shares of common stock, shares				141,205
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes	223	223		$ 21	202
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes, shares				2,091,323
Common shares received in connection with capped call option transactions	0	0		$ (5)	5
Common shares received in connection with capped call option transactions, shares				(515,342)
Exchange of common units of the Operating Partnership	0	28			28		(28)
Exchange of common units of the Operating Partnership, shares				1,000
Adjustment for noncontrolling interest	0	866			866		(866)
Contribution by noncontrolling interest in consolidated property partnership	977						977
Preferred dividends and distributions	(13,250)	(13,250)				(13,250)
Dividends declared per share of common stock and common unit	(121,563)	(119,037)				(119,037)	(2,526)
Ending Balance at Dec. 31, 2014	2,723,936	2,666,210	192,411	$ 863	2,635,900	(162,964)	57,726
Ending Balance, shares at Dec. 31, 2014				86,259,684
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	238,604	234,081				234,081	4,523
Issuance of common stock	387,398	387,398		$ 56	387,342
Issuance of common stock, shares				5,640,033
Issuance of share-based compensation awards	1,692	1,692			1,692
Non-cash amortization of share-based compensation	18,869	18,869			18,869
Exercise of stock options	(14,573)	(14,573)		$ (4)	(14,569)
Exercise of stock options, shares				342,000
Repurchase of common stock and restricted stock units	(7,081)	(7,081)			(7,081)
Repurchase of common stock and restricted stock units, shares				(101,389)
Settlement of restricted stock units for shares of common stock	(1)	(1)		$ 0	(1)
Settlement of restricted stock units for shares of common stock, shares				78,937
Exchange of common units of the Operating Partnership	0	1,223			1,223		(1,223)
Exchange of common units of the Operating Partnership, shares				39,425
Adjustment for noncontrolling interest	0	4,619			4,619		(4,619)
Contribution by noncontrolling interest in consolidated property partnership	474						474
Preferred dividends and distributions	(13,250)	(13,250)				(13,250)
Dividends declared per share of common stock and common unit	(130,628)	(128,129)				(128,129)	(2,499)
Ending Balance at Dec. 31, 2015	$ 3,234,586	3,170,966	192,411	$ 923	3,047,894	(70,262)	63,620
Ending Balance, shares at Dec. 31, 2015	92,258,690			92,258,690
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 303,798	293,788				293,788	10,010
Issuance of common stock	31,117	31,117		$ 4	31,113
Issuance of common stock, shares				451,398
Issuance of share-based compensation awards	1,827	1,827			1,827
Non-cash amortization of share-based compensation	26,624	26,624			26,624
Exercise of stock options	(12,208)	(12,208)		$ (3)	(12,205)
Exercise of stock options, shares				286,500
Repurchase of common stock and restricted stock units	(8,875)	(8,875)		$ (1)	(8,874)
Repurchase of common stock and restricted stock units, shares				(137,126)
Settlement of restricted stock units for shares of common stock	0	0		$ 1	(1)
Settlement of restricted stock units for shares of common stock, shares				109,044
Issuance of common units in connection with acquisition	48,033						48,033
Exchange of common units of the Operating Partnership	0	8,893		$ 2	8,891		(8,893)
Exchange of common units of the Operating Partnership, shares				250,933
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs	453,449	328,997			328,997		124,452
Distributions to noncontrolling interests in consolidated property partnerships	(3,615)	0					(3,615)
Adjustment for noncontrolling interest	0	(8,973)			(8,973)		8,973
Preferred dividends and distributions	(13,250)	(13,250)				(13,250)
Dividends declared per share of common stock and common unit	(326,585)	(318,273)				(318,273)	(8,312)
Ending Balance at Dec. 31, 2016	$ 3,759,317	$ 3,542,995	$ 192,411	$ 932	$ 3,457,649	$ (107,997)	$ 216,322
Ending Balance, shares at Dec. 31, 2016	93,219,439			93,219,439

Consolidated Statements of Equ6

Consolidated Statements of Equity (Parenthetical) - $ / shares	Dec. 13, 2016	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share	$ 1.90	$ 0.375	$ 3.375	$ 1.4	$ 1.40

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 303,798	$ 238,604	$ 183,808
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of real estate assets and leasing costs	213,156	201,482	202,108
Depreciation of non-real estate furniture, fixtures and equipment	4,078	2,812	2,370
Increase in provision for bad debts	0	545	58
Non-cash amortization of share-based compensation awards	21,064	15,537	12,095
Non-cash amortization of deferred financing costs and debt discounts and premiums	2,720	1,853	4,315
Non-cash amortization of net below market rents	(7,166)	(8,449)	(8,328)
Gains on sales of depreciable operating properties	(164,302)	(109,950)	0
Gains on sales of discontinued operations	0	0	(121,922)
Loss (gain) on sales of land	(295)	17,116	3,490
Non-cash amortization of deferred revenue related to tenant-funded tenant improvements	(13,244)	(13,338)	(10,979)
Straight-line rents	(29,629)	(44,383)	(31,782)
Net change in other operating assets	(5,214)	(8,085)	367
Net change in other operating liabilities	19,498	12,496	16,633
Net cash provided by operating activities	345,054	272,008	245,253
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development properties and undeveloped land	351,012	407,969	417,784
Expenditures for acquisitions of development properties and undeveloped land	(33,513)	(139,073)	(147,182)
Expenditures for acquisitions of operating properties	393,767	0	204,546
Expenditures for operating properties and other capital assets	111,961	99,557	132,080
Net proceeds received from dispositions	325,031	319,639	427,544
Net decrease (increase) in restricted cash	(56,015)	65,210	(25,405)
Issuance of notes receivable	(16,100)	(3,000)	0
Decrease (increase) in acquisition-related deposits	1,902	1,998	(1,983)
Net cash used in investing activities	(635,435)	(262,752)	(501,436)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on unsecured revolving credit facility	305,000	250,000	505,000
Repayments on unsecured revolving credit facility	(305,000)	(390,000)	(410,000)
Proceeds from the issuance of secured debt	170,000	0	0
Principal payments and repayments of secured debt	(74,140)	(159,766)	(9,845)
Net proceeds from the issuance of unsecured debt	0	397,776	395,528
Repayments of unsecured debt	0	325,000	83,000
Repayments of exchangeable senior notes	0	0	(172,500)
Borrowings on unsecured debt	0	0	39,000
Financing costs	(2,159)	(4,814)	(8,648)
Net proceeds from issuance of common stock	31,117	387,398	102,229
Proceeds from exercise of stock options	12,208	14,573	21,092
Repurchase of common stock and restricted stock units	(8,875)	(7,081)	(3,533)
Contributions from noncontrolling interests in consolidated property partnerships	453,449	474	977
Distributions to noncontrolling interests in consolidated property partnerships	(3,615)	0	0
Dividends and distributions paid to common stockholders and common unitholders	(137,444)	(126,839)	(118,463)
Dividends and distributions paid to preferred stockholders and preferred unitholders	(13,250)	(13,250)	(13,250)
Net cash provided by financing activities	427,291	23,471	244,587
Net increase (decrease) in cash and cash equivalents	136,910	32,727	(11,596)
Cash and cash equivalents, beginning of year	56,508	23,781	35,377
Cash and cash equivalents, end of year	$ 193,418	$ 56,508	$ 23,781

Consolidated Balance Sheets (KI

Consolidated Balance Sheets (KILROY REALTY, L.P.) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
REAL ESTATE ASSETS
Land and improvements	$ 1,108,971	$ 875,794
Buildings and improvements	4,938,250	4,091,012
Undeveloped land and construction in progress	1,013,533	1,361,340
Total real estate assets held for investment	7,060,754	6,328,146
Accumulated depreciation and amortization	(1,139,853)	(994,241)
Total real estate assets held for investment, net	5,920,901	5,333,905
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET	9,417	117,666
CASH AND CASH EQUIVALENTS	193,418	56,508
RESTRICTED CASH	56,711	696
MARKETABLE SECURITIES	14,773	12,882
CURRENT RECEIVABLES, NET	13,460	11,153
DEFERRED RENT RECEIVABLES, NET	218,977	189,704
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET	208,368	176,683
PREPAID EXPENSES AND OTHER ASSETS, NET	70,608	27,233
TOTAL ASSETS	6,706,633	5,926,430
LIABILITIES:
Secured debt, net	472,772	380,835
Unsecured debt, net	1,847,351	1,844,634
Accounts payable, accrued expenses and other liabilities	202,391	246,323
Accrued distributions	(222,306)	(34,992)
Deferred revenue and acquisition-related intangible liabilities, net	150,360	128,156
Rents received in advance and tenant security deposits	52,080	49,361
Liabilities and deferred revenue of real estate assets held for sale	56	7,543
Total liabilities	2,947,316	2,691,844
COMMITMENTS AND CONTINGENCIES
Partners' Capital:
TOTAL LIABILITIES AND EQUITY	6,706,633	5,926,430
Kilroy Realty, L.P. [Member]
REAL ESTATE ASSETS
Land and improvements	1,108,971	875,794
Buildings and improvements	4,938,250	4,091,012
Undeveloped land and construction in progress	1,013,533	1,361,340
Total real estate assets held for investment	7,060,754	6,328,146
Accumulated depreciation and amortization	(1,139,853)	(994,241)
Total real estate assets held for investment, net	5,920,901	5,333,905
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET	9,417	117,666
CASH AND CASH EQUIVALENTS	193,418	56,508
RESTRICTED CASH	56,711	696
MARKETABLE SECURITIES	14,773	12,882
CURRENT RECEIVABLES, NET	13,460	11,153
DEFERRED RENT RECEIVABLES, NET	218,977	189,704
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET	208,368	176,683
PREPAID EXPENSES AND OTHER ASSETS, NET	70,608	27,233
TOTAL ASSETS	6,706,633	5,926,430
LIABILITIES:
Secured debt, net	472,772	380,835
Unsecured debt, net	1,847,351	1,844,634
Accounts payable, accrued expenses and other liabilities	202,391	246,323
Accrued distributions	(222,306)	(34,992)
Deferred revenue and acquisition-related intangible liabilities, net	150,360	128,156
Rents received in advance and tenant security deposits	52,080	49,361
Liabilities and deferred revenue of real estate assets held for sale	56	7,543
Total liabilities	2,947,316	2,691,844
COMMITMENTS AND CONTINGENCIES
Partners' Capital:
Common units, shares held by the general partner and shares held by common limited partners issued and outstanding, respectively	3,431,768	3,031,609
Total Partners' Capital	3,624,179	3,224,020
Noncontrolling interests in consolidated subsidiaries	135,138	10,566
Total capital	3,759,317	3,234,586
TOTAL LIABILITIES AND EQUITY	6,706,633	5,926,430
Series G Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Partners' Capital:
Preferred Units, Preferred Partners' Capital Accounts	96,155	96,155
Series H Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Partners' Capital:
Preferred Units, Preferred Partners' Capital Accounts	$ 96,256	$ 96,256

Consolidated Balance Sheets (K9

Consolidated Balance Sheets (KILROY REALTY, L.P.) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity Consolidated Carrying Amounts, Real Estate Assets, net	$ 187,254	$ 211,755
Noncontrolling common units of the Operating Partnership	2,381,543	1,764,775
Kilroy Realty, L.P. [Member] | Capital units [Member]
General Partners' Capital Account, Units Issued	93,219,439	92,258,690
General Partners' Capital Account, Units Outstanding	93,219,439	92,258,690
Limited Partners' Capital Account, Units Issued	2,381,543	1,764,775
Noncontrolling common units of the Operating Partnership	2,381,543	1,764,775
Kilroy Realty, L.P. [Member] | Series G Cumulative Redeemable Preferred Unit [Member]
Preferred units, issued	4,000,000	4,000,000
Preferred units outstanding	4,000,000	4,000,000
Preferred stock dividend rate (percentage)	6.875%	6.875%
Preferred stock liquidation preference	$ 100,000	$ 100,000
Kilroy Realty, L.P. [Member] | Series H Cumulative Redeemable Preferred Unit [Member]
Preferred units, issued	4,000,000	4,000,000
Preferred units outstanding	4,000,000	4,000,000
Preferred stock dividend rate (percentage)	6.375%	6.375%
Preferred stock liquidation preference	$ 100,000	$ 100,000

Consolidated Statements of Op10

Consolidated Statements of Operations (KILROY REALTY, L.P.) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
REVENUES:
Rental income	$ 574,413	$ 525,355	$ 466,328
Tenant reimbursements	61,079	53,774	46,717
Other property income	7,080	2,146	8,680
Total revenues	642,572	581,275	521,725
EXPENSES:
Property expenses	113,932	105,378	100,514
Real estate taxes	55,206	50,223	45,197
Provision for bad debts	0	545	58
Ground leases	3,439	3,096	3,075
General and administrative expenses	57,029	48,265	46,152
Acquisition-related expenses	1,902	497	1,479
Depreciation and amortization	217,234	204,294	202,417
Total expenses	448,742	412,298	398,892
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (losses)	1,764	243	561
Interest expense	(55,803)	(57,682)	(67,571)
Total other (expenses) income	(54,039)	(57,439)	(67,010)
Net (loss) gain on sales of land	(295)	17,116	3,490
Gains on sales of depreciable operating properties	164,302	109,950	0
INCOME FROM CONTINUING OPERATIONS	303,798	238,604	59,313
DISCONTINUED OPERATIONS
Income from discontinued operations	0	0	2,573
Net gain on dispositions of discontinued operations	0	0	121,922
Income from discontinued operations	0	0	124,495
NET INCOME	303,798	238,604	183,808
Net income attributable to noncontrolling interests in consolidated subsidiaries	(10,010)	(4,523)	(3,589)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION	293,788	234,081	180,219
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 280,538	$ 220,831	$ 166,969
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	$ 3	$ 2.44	$ 0.52
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	2.97	2.42	0.51
Net income available to common unitholders per unit (dollars per unit)	3	2.44	1.99
Net income available to common unitholders per unit (dollars per unit)	$ 2.97	$ 2.42	$ 1.95
Weighted average common units outstanding - basic	92,342,483	89,854,096	83,090,235
Weighted average common units outstanding - diluted	93,023,034	90,395,775	84,967,720
Kilroy Realty, L.P. [Member]
REVENUES:
Rental income	$ 574,413	$ 525,355	$ 466,328
Tenant reimbursements	61,079	53,774	46,717
Other property income	7,080	2,146	8,680
Total revenues	642,572	581,275	521,725
EXPENSES:
Property expenses	113,932	105,378	100,514
Real estate taxes	55,206	50,223	45,197
Provision for bad debts	0	545	58
Ground leases	3,439	3,096	3,075
General and administrative expenses	57,029	48,265	46,152
Acquisition-related expenses	1,902	497	1,479
Depreciation and amortization	217,234	204,294	202,417
Total expenses	448,742	412,298	398,892
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (losses)	1,764	243	561
Interest expense	(55,803)	(57,682)	(67,571)
Total other (expenses) income	(54,039)	(57,439)	(67,010)
INCOME FROM CONTINUING OPERATIONS BEFORE GAINS ON SALES OF REAL ESTATE	139,791	111,538	55,823
Net (loss) gain on sales of land	(295)	17,116	3,490
Gains on sales of depreciable operating properties	164,302	109,950	0
INCOME FROM CONTINUING OPERATIONS	303,798	238,604	59,313
DISCONTINUED OPERATIONS
Income from discontinued operations	0	0	2,573
Net gain on dispositions of discontinued operations	0	0	121,922
Income from discontinued operations	0	0	124,495
NET INCOME	303,798	238,604	183,808
Net income attributable to noncontrolling interests in consolidated subsidiaries	(3,735)	(467)	(260)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION	300,063	238,137	183,548
PREFERRED DISTRIBUTIONS	13,250	13,250	13,250
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 286,813	$ 224,887	$ 170,298
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	$ 2.99	$ 2.44	$ 0.52
Income (loss) from continuing operations available to common stockholders per share (dollars per share)	2.96	2.42	0.51
Net income available to common unitholders per unit (dollars per unit)	2.99	2.44	1.99
Net income available to common unitholders per unit (dollars per unit)	$ 2.96	$ 2.42	$ 1.94
Weighted average common units outstanding - basic	94,771,688	91,645,578	84,894,498
Weighted average common units outstanding - diluted	95,452,239	92,187,257	86,771,983

Consolidated Statements of Capi

Consolidated Statements of Capital (KILROY REALTY, L.P.) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 35,418	$ 178,113	$ 29,308	$ 44,002	$ 303,798	$ 238,604	$ 183,808
Non-cash amortization of share-based compensation					26,624	18,869	14,471
Settlement of restricted stock units for shares of common stock					0	(1)	(1)
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					(453,449)
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes							223
Common shares received in connection with capped call option transactions							0
Contribution by noncontrolling interest in consolidated subsidiary						474	977
Distributions to noncontrolling interests in consolidated property partnerships					3,615
Preferred dividends and distributions					(13,250)	(13,250)	(13,250)
Noncontrolling Interest In Consolidated Subsidiaries [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income					10,010	4,523	3,589
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					(124,452)
Contribution by noncontrolling interest in consolidated subsidiary						474	977
Distributions to noncontrolling interests in consolidated property partnerships					3,615
Kilroy Realty, L.P. [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		3,234,586		2,723,936	3,234,586	2,723,936	2,516,160
Net income	35,418	178,113	29,308	44,002	303,798	238,604	183,808
Issuance of common units					31,117	387,398	123,860
Issuance of common units in connection with acquisition					48,033
Issuance of share-based compensation awards					1,827	1,692	1,692
Non-cash amortization of share-based compensation					26,624	18,869	14,471
Exercise of stock options					12,208	14,573	21,092
Repurchase of common units and restricted stock units					8,875	7,081	3,533
Settlement of restricted stock units for shares of partner's capital					0	(1)	(1)
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					(453,449)
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes							223
Common shares received in connection with capped call option transactions							0
Contribution by noncontrolling interest in consolidated subsidiary						474	977
Distributions to noncontrolling interests in consolidated property partnerships					(3,615)
Preferred dividends and distributions					(13,250)	(13,250)	(13,250)
Distributions declared per common unit					(326,585)	(130,628)	(121,563)
Ending balance	3,759,317		3,234,586		3,759,317	3,234,586	$ 2,723,936
Kilroy Realty, L.P. [Member] | Partners Capital Common Unit [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common units, units							1,950,599
Kilroy Realty, L.P. [Member] | Total Partners Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		3,224,020		2,714,311	3,224,020	2,714,311	$ 2,507,772
Net income					300,063	238,137	183,548
Issuance of common units					31,117	387,398	123,860
Issuance of common units in connection with acquisition					48,033
Issuance of share-based compensation awards					1,827	1,692	1,692
Non-cash amortization of share-based compensation					26,624	18,869	14,471
Exercise of stock options						14,573	21,092
Repurchase of common units and restricted stock units					8,875	7,081	3,533
Settlement of restricted stock units for shares of partner's capital					0	(1)	(1)
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					(328,997)
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes							223
Common shares received in connection with capped call option transactions							0
Preferred dividends and distributions					(13,250)	(13,250)	(13,250)
Distributions declared per common unit					(326,585)	(130,628)	(121,563)
Ending balance	3,624,179		3,224,020		3,624,179	3,224,020	2,714,311
Kilroy Realty, L.P. [Member] | Partners Capital Preferred Units [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		192,411		192,411	192,411	192,411	192,411
Ending balance	192,411		192,411		192,411	192,411	192,411
Kilroy Realty, L.P. [Member] | Partners Capital Common Unit [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		$ 3,031,609		$ 2,521,900	$ 3,031,609	$ 2,521,900	$ 2,315,361
Beginning balance units		94,023,465		88,063,884	94,023,465	88,063,884	83,959,144
Net income					$ 300,063	$ 238,137	$ 183,548
Issuance of common units					$ 31,117	$ 387,398	123,860
Issuance of common units, units					451,398	5,640,033
Issuance of common units in connection with acquisition					$ 48,033
Issuance of common units in connection with acquisition, units					867,701
Issuance of share-based compensation awards					$ 1,827	$ 1,692	1,692
Non-cash amortization of share-based compensation					26,624	18,869	14,471
Exercise of stock options					$ 12,208	$ 14,573	$ 21,092
Exercise of stock options, units					286,500	342,000	495,000
Repurchase of common units and restricted stock units					$ 8,875	$ 7,081	$ 3,533
Repurchase of common units and restricted stock units, units					137,126	101,389	58,045
Settlement of restricted stock units for shares of common stock					$ 0	$ (1)	$ (1)
Settlement of restricted stock units for shares of common stock units					109,044	78,937	141,205
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					$ (328,997)
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes							$ 223
Common shares issued in connection with settlement of 4.25% Exchangeable Senior Notes, units							2,091,323
Common shares received in connection with capped call option transactions, units							(515,342)
Preferred dividends and distributions					(13,250)	$ (13,250)	$ (13,250)
Distributions declared per common unit					326,585	130,628	121,563
Ending balance	$ 3,431,768		$ 3,031,609		$ 3,431,768	$ 3,031,609	$ 2,521,900
Ending balance units	95,600,982		94,023,465		95,600,982	94,023,465	88,063,884
Kilroy Realty, L.P. [Member] | Noncontrolling Interest In Consolidated Subsidiaries [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		$ 10,566		$ 9,625	$ 10,566	$ 9,625	$ 8,388
Net income					3,735	467	260
Initial contributions from noncontrolling interest in consolidated property partnership, net of transaction costs					124,452
Contribution by noncontrolling interest in consolidated subsidiary						474	977
Distributions to noncontrolling interests in consolidated property partnerships					3,615
Ending balance	$ 135,138		$ 10,566		$ 135,138	$ 10,566	$ 9,625

Consolidated Statements of Ca12

Consolidated Statements of Capital (KILROY REALTY, L.P.) - Parenthetical - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Kilroy Realty, L.P. [Member]
Distributions declared per common unit	$ 3.375	$ 1.4	$ 1.40

Consolidated Statements of Ca13

Consolidated Statements of Cash Flows (KILROY REALTY, L.P.) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 303,798	$ 238,604	$ 183,808
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of real estate assets and leasing costs	213,156	201,482	202,108
Depreciation of non-real estate furniture, fixtures and equipment	4,078	2,812	2,370
Increase in provision for bad debts	0	545	58
Non-cash amortization of share-based compensation awards	21,064	15,537	12,095
Non-cash amortization of deferred financing costs and debt discounts and premiums	2,720	1,853	4,315
Non-cash amortization of net below market rents	(7,166)	(8,449)	(8,328)
Gains on sales of depreciable operating properties	(164,302)	(109,950)	0
Gains on sales of discontinued operations	0	0	(121,922)
Loss (gain) on sales of land	295	(17,116)	(3,490)
Non-cash amortization of deferred revenue related to tenant-funded tenant improvements	(13,244)	(13,338)	(10,979)
Straight-line rents	(29,629)	(44,383)	(31,782)
Net change in other operating assets	(5,214)	(8,085)	367
Net change in other operating liabilities	19,498	12,496	16,633
Net cash provided by operating activities	345,054	272,008	245,253
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development properties and undeveloped land	(351,012)	(407,969)	(417,784)
Expenditures for acquisitions of development properties and undeveloped land	(33,513)	(139,073)	(147,182)
Expenditures for acquisitions of operating properties	(393,767)	0	(204,546)
Expenditures for acquisitions of operating properties	(111,961)	(99,557)	(132,080)
Net proceeds received from dispositions	325,031	319,639	427,544
Net decrease (increase) in restricted cash	(56,015)	65,210	(25,405)
Issuance of notes receivable	(16,100)	(3,000)	0
Decrease (increase) in acquisition-related deposits	1,902	1,998	(1,983)
Net cash used in investing activities	(635,435)	(262,752)	(501,436)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on unsecured line of credit	305,000	250,000	505,000
Repayments on unsecured revolving credit facility	(305,000)	(390,000)	(410,000)
Proceeds from the issuance of secured debt	170,000	0	0
Principal payments and repayments of secured debt	(74,140)	(159,766)	(9,845)
Net proceeds from the issuance of unsecured debt	0	397,776	395,528
Repayments of unsecured debt	0	(325,000)	(83,000)
Repayments of exchangeable senior notes	0	0	(172,500)
Borrowings on unsecured debt	0	0	39,000
Financing costs	(2,159)	(4,814)	(8,648)
Proceeds from exercise of stock options	12,208	14,573	21,092
Repurchase/redemption of common units and restricted stock units	(8,875)	(7,081)	(3,533)
Contributions from noncontrolling interests in consolidated property partnerships	453,449	474	977
Distributions to noncontrolling interests in consolidated property partnerships	(3,615)	0	0
Distributions paid to common unitholders	(137,444)	(126,839)	(118,463)
Distributions paid to preferred unitholders	(13,250)	(13,250)	(13,250)
Net cash provided by financing activities	427,291	23,471	244,587
Net increase (decrease) in cash and cash equivalents	136,910	32,727	(11,596)
Cash and cash equivalents, beginning of year	56,508	23,781	35,377
Cash and cash equivalents, end of year	193,418	56,508	23,781
Kilroy Realty, L.P. [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	303,798	238,604	183,808
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of real estate assets and leasing costs	213,156	201,482	202,108
Depreciation of non-real estate furniture, fixtures and equipment	4,078	2,812	2,370
Increase in provision for bad debts	0	545	58
Non-cash amortization of share-based compensation awards	21,064	15,537	12,095
Non-cash amortization of deferred financing costs and debt discounts and premiums	2,720	1,853	4,315
Non-cash amortization of net below market rents	(7,166)	(8,449)	(8,328)
Gains on sales of depreciable operating properties	(164,302)	(109,950)	0
Gains on sales of discontinued operations	0	0	(121,922)
Loss (gain) on sales of land	295	(17,116)	(3,490)
Non-cash amortization of deferred revenue related to tenant-funded tenant improvements	(13,244)	(13,338)	(10,979)
Straight-line rents	(29,629)	(44,383)	(31,782)
Net change in other operating assets	(5,214)	(8,085)	367
Net change in other operating liabilities	19,498	12,496	16,633
Net cash provided by operating activities	345,054	272,008	245,253
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development properties and undeveloped land	(351,012)	(407,969)	(417,784)
Expenditures for acquisitions of development properties and undeveloped land	(33,513)	(139,073)	(147,182)
Expenditures for acquisitions of operating properties	(393,767)	0	(204,546)
Expenditures for acquisitions of operating properties	(111,961)	(99,557)	(132,080)
Net proceeds received from dispositions	325,031	319,639	427,544
Net decrease (increase) in restricted cash	(56,015)	65,210	(25,405)
Issuance of notes receivable	(16,100)	(3,000)	0
Decrease (increase) in acquisition-related deposits	1,902	1,998	(1,983)
Net cash used in investing activities	(635,435)	(262,752)	(501,436)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on unsecured line of credit	305,000	250,000	505,000
Repayments on unsecured revolving credit facility	(305,000)	(390,000)	(410,000)
Proceeds from the issuance of secured debt	170,000	0	0
Principal payments and repayments of secured debt	(74,140)	(159,766)	(9,845)
Net proceeds from the issuance of unsecured debt	0	397,776	395,528
Repayments of unsecured debt	0	(325,000)	(83,000)
Repayments of exchangeable senior notes	0	0	(172,500)
Borrowings on unsecured debt	0	0	39,000
Financing costs	(2,159)	(4,814)	(8,648)
Net proceeds from issuance of common units	31,117	387,398	102,229
Proceeds from exercise of stock options	12,208	14,573	21,092
Repurchase/redemption of common units and restricted stock units	(8,875)	(7,081)	(3,533)
Contributions from noncontrolling interests in consolidated property partnerships	453,449	474	977
Distributions to noncontrolling interests in consolidated property partnerships	(3,615)	0	0
Distributions paid to common unitholders	(137,444)	(126,839)	(118,463)
Distributions paid to preferred unitholders	(13,250)	(13,250)	(13,250)
Net cash provided by financing activities	427,291	23,471	244,587
Net increase (decrease) in cash and cash equivalents	136,910	32,727	(11,596)
Cash and cash equivalents, beginning of year	56,508	23,781	35,377
Cash and cash equivalents, end of year	$ 193,418	$ 56,508	$ 23,781

Organization and Ownership

Organization and Ownership	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Ownership	Organization and Ownership Kilroy Realty Corporation (the “Company”) is a self-administered real estate investment trust (“REIT”) active in premier office and mixed-use submarkets along the West Coast. We own, develop, acquire and manage real estate assets, consisting primarily of Class A properties in the coastal regions of Los Angeles, Orange County, San Diego County, the San Francisco Bay Area and Greater Seattle, which we believe have strategic advantages and strong barriers to entry. Class A real estate encompasses attractive and efficient buildings of high quality that are attractive to tenants, are well-designed and constructed with above-average material, workmanship and finishes and are well-maintained and managed. We qualify as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”). The Company’s common stock is publicly traded on the New York Stock Exchange (“NYSE”) under the ticker symbol “KRC.” We own our interests in all of our real estate assets through Kilroy Realty, L.P. (the “Operating Partnership”) and Kilroy Realty Finance Partnership, L.P. (the “Finance Partnership”). We generally conduct substantially all of our operations through the Operating Partnership. Unless stated otherwise or the context indicates otherwise, the terms “Kilroy Realty Corporation” or the “Company,” “we,” “our,” and “us” refer to Kilroy Realty Corporation and its consolidated subsidiaries and the term “Operating Partnership” refers to Kilroy Realty, L.P. and its consolidated subsidiaries. The descriptions of our business, employees, and properties apply to both the Company and the Operating Partnership. Our stabilized portfolio of operating properties was comprised of the following properties at December 31, 2016 : Number of Buildings Rentable Square Feet (unaudited) Number of Tenants Percentage Occupied (unaudited) Percentage Leased (unaudited) Stabilized Office Properties 108 14,025,856 549 96.0 % 97.0 % Number of Number of Units Percentage Occupied (unaudited) Percentage Leased (unaudited) Stabilized Residential Property 1 200 46.0 % 56.5 % Our stabilized portfolio includes all of our properties with the exception of development and redevelopment properties currently under construction or committed for construction, “lease-up” properties, real estate assets held for sale and undeveloped land. We define redevelopment properties as those properties for which we expect to spend significant development and construction costs on the existing or acquired buildings pursuant to a formal plan, the intended result of which is a higher economic return on the property. We define “lease-up” properties as properties we recently developed or redeveloped that have not yet reached 95% occupancy and are within one year following cessation of major construction activities. During the year ended December 31, 2016 , we added three development projects to our stabilized office portfolio consisting of two projects totaling 640,942 rentable square feet in San Francisco, California and a 73,000 rentable square foot project in Del Mar, California. These three properties were included in our stabilized office portfolio as of December 31, 2016 . As of December 31, 2016 , the following properties were excluded from our stabilized portfolio. We did not have any redevelopment properties as of December 31, 2016. Number of Properties/Projects Estimated Office Rentable Square Feet (unaudited) Properties held for sale (1) 1 67,995 Development project in “ lease-up" (2) 1 377,000 Development projects under construction (2)(3) 3 1,100,000 _______________ (1) See Note 4 “Dispositions and Real Estate Assets Held for Sale” for additional information. (2) Estimated rentable square feet upon completion. (3) Development projects under construction also include 96,000 square feet of retail space and 237 residential units in addition to the estimated office rentable square feet noted above. Our stabilized portfolio also excludes our near-term and future development pipeline, which as of December 31, 2016 is comprised of seven potential development sites, representing approximately 54 gross acres of undeveloped land. As of December 31, 2016 , all of our properties and development projects were owned and all of our business was conducted in the state of California with the exception of twelve office properties and one future development project located in the state of Washington. All of our properties and development projects are 100% owned, excluding four office properties owned by three consolidated property partnerships, and an office property held by a consolidated variable interest entity for a future transaction intended to qualify as like-kind exchanges pursuant to Section 1031 of the Code (“Section 1031 Exchanges”). Two of the three property partnerships, 100 First Street Member, LLC (“100 First LLC”) and 303 Second Street Member, LLC (“303 Second LLC”), each owned one office property in San Francisco, California through subsidiary REITs. As of December 31, 2016 , the Company owned a 56% equity interest in both 100 First LLC and 303 Second LLC. The third property partnership, Redwood City Partners, LLC (“Redwood LLC”) owned two office properties in Redwood City, California. As of December 31, 2016 , the Company owned an approximate 93% common equity interest in Redwood LLC. The remaining interests in all three property partnerships were owned by unrelated third parties. (See Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements” and Note 12 “Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements” to our consolidated financial statements included in this report for additional information). As of December 31, 2016 , the Company owned an approximate 97.5% common general partnership interest in the Operating Partnership. The remaining approximate 2.5% common limited partnership interest in the Operating Partnership as of December 31, 2016 was owned by non-affiliated investors and certain of our executive officers and directors. Both the general and limited common partnership interests in the Operating Partnership are denominated in common units. Generally, the number of common units held by the Company is equivalent to the number of outstanding shares of the Company’s common stock, and the rights of all the common units to quarterly distributions and payments in liquidation mirror those of the Company’s common stockholders. The common limited partners have certain redemption rights as provided in the Operating Partnership’s Seventh Amended and Restated Agreement of Limited Partnership, as amended, the “Partnership Agreement” (see Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements” for additional information). Kilroy Realty Finance, Inc., a wholly-owned subsidiary of the Company, is the sole general partner of the Finance Partnership and owns a 1.0% common general partnership interest. The Operating Partnership owns the remaining 99.0% common limited partnership interest. We conduct substantially all of our development activities through Kilroy Services, LLC (“KSLLC”), which is a wholly owned subsidiary of the Operating Partnership. With the exception of the Operating Partnership and our consolidated property partnerships, all of our subsidiaries are wholly-owned.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Basis of Presentation and Significant Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Basis of Presentation The consolidated financial statements of the Company include the consolidated financial position and results of operations of the Company, the Operating Partnership, the Finance Partnership, KSLLC, 303 Second LLC, 100 First LLC, Redwood LLC and all of our wholly-owned and controlled subsidiaries. The consolidated financial statements of the Operating Partnership include the consolidated financial position and results of operations of the Operating Partnership, the Finance Partnership, KSLLC, 303 Second LLC, 100 First LLC, Redwood LLC and all wholly-owned and controlled subsidiaries of the Operating Partnership. All intercompany balances and transactions have been eliminated in the consolidated financial statements. Effective January 1, 2016, the Company adopted Financial Accounting Standards Board ("FASB") Accounting Standards Update (“ASU”) No. 2015-03 and No. 2015-15, which requires that debt issuance costs related to a recognized debt liability be presented on the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. However, for line-of-credit arrangements, entities may defer and present debt issuance costs as an asset and amortize the costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. As a result of our adoption of the guidance, $1.1 million of deferred financing costs as of December 31, 2015 were reclassified to reduce secured debt, net and $12.0 million of deferred financing costs as of December 31, 2015 were reclassified to reduce unsecured debt, net in the December 31, 2015 balances on our consolidated balance sheets. In addition, $4.6 million of deferred financing costs relating to our unsecured line of credit as of December 31, 2015 were reclassified to prepaid expenses and other assets, net in the December 31, 2015 balances on our consolidated balance sheets. The guidance did not have a material impact on our consolidated financial statements. Partially Owned Entities and Variable Interest Entities Effective January 1, 2016, the Company adopted FASB ASU No. 2015-02 (“ASU 2015-02”), which amended certain guidance with respect to the evaluation of Variable Interest Entities (“VIEs”) and when a reporting entity is required to consolidate certain legal entities. Specifically, the amendments: (i) modify the evaluation of whether limited partnerships and similar legal entities are VIEs or voting interest entities, (ii) eliminate the presumption that a general partner should consolidate a limited partnership, (iii) affect the consolidation analysis of reporting entities that are involved with VIEs, and (iv) provide a scope exception for certain entities. Under the new guidance, effective January 1, 2016, the Operating Partnership was determined to be a VIE of the Company as the Operating Partnership is a limited partnership in which the common limited partners do not have substantive kick-out rights or participating rights. However, given that the Company was deemed to be the primary beneficiary of the Operating Partnership because the Company has the ability to control the activities that most significantly impact the Operating Partnership's economic performance, the adoption of this new guidance and the conclusion that the Operating Partnership was a VIE did not have any impact on our consolidated financial statements since the conclusion to consolidate the Operating Partnership still applied. The Operating Partnership was the only new VIE identified as part of the adoption of the guidance as of January 1, 2016. At December 31, 2016 the consolidated financial statements of the Company included three VIEs in addition to the Operating Partnership: 303 Second LLC; 100 First LLC; and an entity established during the fourth quarter of 2016 to facilitate a Section 1031 Exchange. At December 31, 2016 , the Company and the Operating Partnership were determined to be the primary beneficiary of these three VIEs as since we had the ability to control the activities that most significantly impact each of the VIEs’ economic performance. As of December 31, 2016 , the three VIEs’ total assets, liabilities and noncontrolling interest included on our consolidated balance sheet were approximately $654.3 million (of which $588.6 million related to real estate held for investment), approximately $166.1 million and approximately $124.3 million , respectively. Revenues, income and net assets generated by 303 Second LLC and 100 First LLC may only be used to settle their contractual obligations, which primarily consist of operating expenses, mortgage debt related payments, capital expenditures and required distributions. In January 2017, the Section 1031 Exchange was successfully completed and the entity established for the 1031 Exchange was no longer a VIE. At December 31, 2015 , the consolidated financial statements of the Company and the Operating Partnership included two VIEs in which we were deemed to be the primary beneficiary. One VIE, Redwood LLC, was established in the second quarter of 2013 in connection with an undeveloped land acquisition. During the year ended December 31, 2016 , Redwood LLC had a VIE reconsideration event and was determined to no longer be a VIE. The other VIE was established during the fourth quarter of 2015 to facilitate potential Section 1031 Exchanges and was terminated during 2016. The impact of consolidating the VIEs increased the Company’s total assets, liabilities and noncontrolling interests as of December 31, 2015 by approximately $203.3 million (of which $187.3 million related to real estate held for investment on our consolidated balance sheet), approximately $28.8 million and approximately $6.5 million , respectively. Our accounting policy is to consolidate entities in which we have a controlling financial interest and significant decision making control over the entity's operations. In determining whether we have a controlling financial interest in a partially owned entity and the requirement to consolidate the accounts of that entity, we consider factors such as ownership interest, board representation, management representation, size of our investment (including loans), authority to control decisions, and contractual and substantive participating rights of the members. In addition to evaluating control rights, we consolidate entities in which the other members have no substantive kick-out rights to remove the Company as the managing member. We also evaluate whether the entity is a variable interest entity and whether we are the primary beneficiary. VIEs are entities in which the equity investors do not have sufficient equity at risk to finance their endeavors without additional financial support or the holders of the equity investment at risk do not have a controlling financial interest. We are deemed to be the primary beneficiary of a VIE when we have the power to direct the activities of the VIE that most significantly impact the VIEs’ economic performance and the obligation to absorb losses or receive benefits that could potentially be significant to the VIE. If the requirements for consolidation are not met, the Company would account for investments under the equity method of accounting if we have the ability to exercise significant influence over the entity. Equity method investments would be initially recorded at cost and subsequently adjusted for our share of net income or loss and cash contributions and distributions each period. The Company did not have any equity method investments at December 31, 2016 or December 31, 2015 . Significant Accounting Policies Acquisitions We record the acquired tangible and intangible assets and assumed liabilities of acquisitions of operating properties and development and redevelopment opportunities that meet the accounting criteria to be accounted for as business combinations at fair value at the acquisition date. The acquired assets and assumed liabilities for an acquisition generally include but are not limited to (i) land and improvements, buildings and improvements, undeveloped land and construction in progress and (ii) identified tangible and intangible assets and liabilities associated with in-place leases, including tenant improvements, leasing costs, value of above-market and below-market operating leases and ground leases, acquired in-place lease values and tenant relationships, if any. Any debt assumed and equity (including common units of the Operating Partnership) issued in connection with a property acquisition is recorded at fair value on the date of acquisition. The fair value of land and improvements is derived from comparable sales of land and improvements within the same submarket and/or region. The fair value of buildings and improvements, tenant improvements and leasing costs considers the value of the property as if it was vacant as well as current replacement costs and other relevant market rate information. The fair value of the above-market or below-market component of an acquired in-place operating lease is based upon the present value (calculated using a market discount rate) of the difference between (i) the contractual rents to be paid pursuant to the lease over its remaining non-cancellable lease term and (ii) our estimate of the rents that would be paid using fair market rental rates and rent escalations at the date of acquisition measured over the remaining non-cancellable term of the lease for above-market operating leases and the initial non-cancellable term plus the term of any below-market fixed rate renewal options, if applicable, for below-market operating leases. Our below-market operating leases generally do not include fixed rate or below-market renewal options. The amounts recorded for above-market operating leases are included in deferred leasing costs and acquisition-related intangible assets, net on the balance sheet and are amortized on a straight-line basis as a reduction of rental income over the remaining term of the applicable leases. The amounts recorded for below-market operating leases are included in deferred revenue and acquisition-related intangible liabilities, net on the balance sheet and are amortized on a straight-line basis as an increase to rental income over the remaining term of the applicable leases plus the term of any below-market fixed rate renewal options, if applicable. The amortization of the below-market ground lease obligation is recorded as an increase to ground lease expense in the consolidated statements of operations for the periods presented. The amortization of the above-market ground lease obligation is recorded as a decrease to ground lease expense in the consolidations statements of operations for the periods presented. The fair value of acquired in-place leases is derived based on our assessment of lost revenue and costs incurred for the period required to lease the “assumed vacant” property to the occupancy level when purchased. The amount recorded for acquired in-place leases is included in deferred leasing costs and acquisition-related intangible assets, net on the balance sheet and amortized as an increase to depreciation and amortization expense over the remaining term of the applicable leases. Fully amortized intangible assets are written off each quarter. We record the acquisition of undeveloped land that does not meet the accounting criteria to be accounted for as business combinations and the subsequent acquisition of the fee interest in land and improvements underlying our properties at the purchase price paid and capitalize the associated acquisition costs. During the years ended December 31, 2016 , 2015 and 2014 we capitalized $0.5 million , $1.1 million and $4.5 million , respectively, in acquisition costs associated with development acquisitions. Operating Properties Operating properties are generally carried at historical cost less accumulated depreciation. Properties held for sale are reported at the lower of the carrying value or the fair value less estimated cost to sell. The cost of operating properties includes the purchase price or development costs of the properties. Costs incurred for the renovation and betterment of the operating properties are capitalized to our investment in that property. Maintenance and repairs are charged to expense as incurred. When evaluating properties to be held and used for potential impairment, we first evaluate whether there are any indicators of impairment for any of our properties. If any impairment indicators are present for a specific property, we then perform an undiscounted cash flow analysis and compare the net carrying amount of the property to the property’s estimated undiscounted future cash flow over the anticipated holding period. If the estimated undiscounted future cash flow is less than the net carrying amount of the property, we then perform an impairment loss calculation to determine if the fair value of the property is less than the net carrying value of the property. Our impairment loss calculation compares the net carrying amount of the property to the property’s estimated fair value, which may be based on estimated discounted future cash flow calculations or third-party valuations or appraisals. We would recognize an impairment loss if the asset’s net carrying amount exceeds the asset’s estimated fair value. If we were to recognize an impairment loss, the estimated fair value of the asset (less costs to sell for assets held for sale) would become its new cost basis. For a depreciable long-lived asset, the new cost basis would be depreciated (amortized) over the remaining useful life of that asset. Cost Capitalization All costs clearly associated with the development, redevelopment and construction of a property are capitalized as project costs, including internal compensation costs. In addition, the following costs are capitalized as project costs during periods in which activities necessary to prepare development and redevelopment properties for its intended use are in progress: pre-construction costs essential to the development of the property, interest, real estate taxes and insurance. • For office development and redevelopment properties that are pre-leased, we cease capitalization when revenue recognition commences, which is upon substantial completion of tenant improvements deemed to be the Company's asset for accounting purposes. • For office development and redevelopment properties that are not pre-leased, we may not immediately build out the tenant improvements. Therefore, we cease capitalization when revenue recognition commences upon substantial completion of the tenant improvements deemed to be the Company's asset for accounting purposes, but in any event, no later than one year after the cessation of major construction activities. We also cease capitalization on a development or redevelopment property when activities necessary to prepare the property for its intended use have been suspended. • For office development or redevelopment properties with multiple tenants and staged leasing, we cease capitalization and begin depreciation on the portion of the development or redevelopment property for which revenue recognition has commenced. • For residential development properties, we cease capitalization when the property is substantially complete and available for occupancy. Once major construction activity has ceased and the development or redevelopment property is in the lease-up phase, the costs capitalized to construction in progress are transferred to land and improvements, buildings and improvements, and deferred leasing costs on our consolidated balance sheets as the historical cost of the property. Depreciation and Amortization of Buildings and Improvements The costs of buildings and improvements and tenant improvements are depreciated using the straight-line method of accounting over the estimated useful lives set forth in the table below. Depreciation expense for buildings and improvements, including discontinued operations, for the three years ended December 31, 2016 , 2015 , and 2014 was $172.0 million , $159.5 million and $153.8 million , respectively. Asset Description Depreciable Lives Buildings and improvements 25 – 40 years Tenant improvements 1 – 20 years (1) ________________________ (1) Tenant improvements are amortized over the shorter of the lease term or the estimated useful life. Real Estate Assets Held for Sale, Dispositions and Discontinued Operations A real estate asset is classified as held for sale when certain criteria are met, including but not limited to the availability of the asset for immediate sale, the existence of an active program to locate a buyer and the probable sale or transfer of the asset within one year. If such criteria are met, we present the applicable assets and liabilities related to the real estate asset held for sale, if material, separately on the balance sheet and we would cease to record depreciation and amortization expense. Real estate assets held for sale are reported at the lower of their carrying value or their estimated fair value less the estimated costs to sell. As of December 31, 2016 , we classified one operating property located in San Diego, California as held for sale. As of December 31, 2015 , we classified four operating properties and one undeveloped land parcel located in San Diego, California as held for sale. Effective January 1, 2015, the Company adopted FASB ASU No. 2014-08 (“ASU 2014-08”), which changed the criteria for reporting discontinued operations while enhancing disclosures in this area. Under the new guidance, only property disposals representing a strategic shift that has (or will have) a major effect on an entity's operations and financial results, such as a major line of business, a major geographical area or a major equity investment, are required to be presented as discontinued operations. If we were to determine that the property disposition represents a strategic shift, the revenues, expenses and net gain (loss) on dispositions of the property would be recorded in discontinued operations for all periods presented through the date of the applicable disposition. The Company adopted and applied the new guidance on a prospective basis as required by ASU 2014-08. Therefore, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are presented in continuing operations for all periods presented. In accordance with this guidance, the operations of the six properties sold during the year ended December 31, 2016 and the ten properties sold during the year ended December 31, 2015 are presented in continuing operations for the years ended December 31, 2016 and December 31, 2015 , respectively. Prior to January 1, 2015, the revenues and expenses of operating properties that have been sold, if material, and the revenues and expenses of operating properties that have been classified as held for sale, if material, are reported in the consolidated statements of operations as discontinued operations for all periods presented through the date of the applicable disposition. The net gains (losses) on disposition of operating properties are reported in the consolidated statements of operations as discontinued operations in the period the properties are sold. In determining whether the revenues, expenses, and net gains (losses) on dispositions of operating properties are reported as discontinued operations, we evaluate whether we have any significant continuing involvement in the operations, leasing, or management of the sold property. If we were to determine that we had any significant continuing involvement, the revenues, expenses and net gain (loss) on dispositions of the operating property would not be recorded in discontinued operations. For the year ended December 31, 2014, discontinued operations includes the net income and gains on all of the properties sold in 2014. The net gains (losses) on dispositions of non-depreciable real estate property, including land, are reported in the consolidated statements of operations as gains (losses) on sale of land within continuing operations in the period the land is sold. Revenue Recognition We recognize revenue from rent, tenant reimbursements, parking and other revenue once all of the following criteria are met: (i) the agreement has been fully executed and delivered, (ii) services have been rendered, (iii) the amount is fixed or determinable and (iv) the collectability of the amount is reasonably assured. Minimum annual rental revenues are recognized in rental revenues on a straight-line basis over the term of the related lease. Rental revenue recognition commences when the tenant takes possession or controls the physical use of the leased space. In order for the tenant to take possession, the leased space must be substantially complete and ready for its intended use. In order to determine whether the leased space is substantially ready for its intended use, we begin by determining whether the Company or the tenant owns the tenant improvements. When we conclude that the Company is the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is generally when Company owned tenant improvements are substantially complete. In certain instances, when we conclude that the Company is not the owner (the tenant is the owner) of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space. When we conclude that the Company is the owner of tenant improvements, we record the cost to construct the tenant improvements, including costs paid for or reimbursed by the tenants, as a capital asset. For these tenant improvements, we record the amount funded by or reimbursed by the tenants as deferred revenue, which is amortized on a straight-line basis as additional rental income over the term of the related lease. When we conclude that the tenant is the owner of tenant improvements for accounting purposes, we record our contribution towards those improvements as a lease incentive, which is included in deferred leasing costs and acquisition-related intangible assets, net on our consolidated balance sheets and amortized as a reduction to rental income on a straight-line basis over the term of the lease. For residential properties, we commence revenue recognition upon occupancy of the units by the tenants. Residential rental revenue is recognized on a straight-line basis over the term of the related lease, net of any concessions. Tenant Reimbursements Reimbursements from tenants, consisting of amounts due from tenants for common area maintenance, real estate taxes and other recoverable costs, are recognized as revenue in the period the recoverable costs are incurred. Tenant reimbursements are recognized and recorded on a gross basis, as we are generally the primary obligor with respect to purchasing goods and services from third-party suppliers, have discretion in selecting the supplier, and have credit risk. Other Property Income Other property income primarily includes amounts recorded in connection with lease terminations, tenant bankruptcy settlement payments and property damage settlement related payments. Lease termination fees are amortized over the remaining lease term, if applicable. If there is no remaining lease term, they are recognized when received and realized. Other property income also includes miscellaneous income from tenants, such as fees related to the restoration of leased premises to their original condition and fees for late rental payments. Allowances for Uncollectible Tenant and Deferred Rent Receivables We carry our current and deferred rent receivables net of allowances for uncollectible amounts. Our determination of the adequacy of these allowances is based primarily upon evaluations of individual receivables, current economic conditions, and other relevant factors. The allowances are increased or decreased through the provision for bad debts on our consolidated statements of operations. Cash and Cash Equivalents We consider all highly-liquid investments with original maturities of three months or less to be cash equivalents. Restricted Cash Restricted cash consists of cash proceeds from dispositions that are temporarily held at qualified intermediaries for purposes of facilitating potential Section 1031 Exchanges and cash held in escrow related to acquisition and disposition holdbacks. Restricted cash also includes cash held as collateral to provide credit enhancement for the Operating Partnership’s mortgage debt, including cash reserves for capital expenditures, tenant improvements and property taxes. As of December 31, 2016 , we had $48.4 million of restricted cash held at qualified intermediaries for the purpose of facilitating Section 1031 Exchanges. In January 2017, the Section 1031 Exchange was completed and the cash was released from the qualified intermediary. As of December 31, 2015 , we had no restricted cash held at qualified intermediaries for the purpose of facilitating Section 1031 Exchanges. Marketable Securities / Deferred Compensation Plan Marketable securities reported in our consolidated balance sheets represent the assets held in connection with the Kilroy Realty Corporation 2007 Deferred Compensation Plan (the “Deferred Compensation Plan”) (see Note 16 “Employee Benefit Plans” for additional information). The Deferred Compensation Plan assets are held in a limited rabbi trust and invested in various mutual and money market funds. As a result, the marketable securities are treated as trading securities for financial reporting purposes and are adjusted to fair value at the end of each accounting period, with the corresponding gains and losses recorded in interest income and other net investment gains. At the time eligible management employees (“Participants”) defer compensation or earn mandatory Company contributions, or if we were to make a discretionary contribution, we record compensation cost and a corresponding deferred compensation plan liability, which is included in accounts payable, accrued expenses, and other liabilities on our consolidated balance sheets. This liability is adjusted to fair value at the end of each accounting period based on the performance of the benchmark funds selected by each Participant, and the impact of adjusting the liability to fair value is recorded as an increase or decrease to compensation cost. The impact of adjusting the deferred compensation plan liability to fair value and the changes in the value of the marketable securities held in connection with the Deferred Compensation Plan generally offset and therefore do not significantly impact net income. Deferred Leasing Costs Costs incurred in connection with successful property leasing are capitalized as deferred leasing costs and classified as investing activities in the statement of cash flows. Deferred leasing costs consist primarily of leasing commissions and also include certain internal payroll costs and lease incentives, which are amortized using the straight-line method of accounting over the lives of the leases which generally range from one to 20 years. We reevaluate the remaining useful lives of leasing costs as the creditworthiness of our tenants and economic and market conditions change. If we determine that the estimated remaining life of a lease has changed, we adjust the amortization period accordingly. Fully amortized deferred leasing costs are written off each quarter. Deferred Financing Costs Financing costs related to the origination or assumption of long-term debt are deferred and generally amortized using the straight-line method of accounting, which approximates the effective interest method, over the contractual terms of the applicable financings. Fully amortized deferred financing costs are written off when the corresponding financing is repaid. As of December 31, 2016 and 2015 , our secured debt was reported net of unamortized deferred financing costs of $1.4 million and $1.1 million , respectively, and our unsecured debt was reported net of unamortized deferred financing costs of $10.1 million and $12.0 million , respectively. Deferred financing costs related to our unsecured line of credit were reported in prepaid expenses and other assets net of accumulated amortization of $5.7 million and $4.3 million as of December 31, 2016 and 2015 , respectively. Debt Discounts and Premiums Original issuance debt discounts and discounts/premiums related to recording debt acquired in connection with operating property acquisitions at fair value are generally amortized and accreted on a straight-line basis, which approximates the effective interest method. Discounts are recorded as additional interest expense from date of issuance or acquisition through the contractual maturity date of the related debt. Premiums are recorded as a reduction to interest expense from the date of issuance or acquisition through the contractual maturity date of the related debt. Our secured debt is presented including unamortized premiums of $4.4 million and $6.2 million as of December 31, 2016 and 2015 , respectively. Our unsecured senior notes are presented net of unamortized discounts of $6.6 million and $7.4 million , as of December 31, 2016 and 2015 , respectively. Noncontrolling Interests - Common Units of the Operating Partnership in the Company's Consolidated Financial Statements Common units of the Operating Partnership within noncontrolling interests in the Company’s consolidated financial statements represent the common limited partnership interests in the Operating Partnership not held by the Company (“noncontrolling common units”). Noncontrolling common units are presented in the equity section of the Company’s consolidated balance sheets and are reported at their proportionate share of the net assets of the Operating Partnership. Noncontrolling interests with redemption provisions that permit the issuer to settle in either cash or shares of common stock must be further evaluated to determine whether equity or temporary equity classification on the balance sheet is appropriate. Since the common units contain such a provision, we evaluated the accounting guidance and determined that the common units qualify for equity presentation in the Company’s consolidated financial statements. Net income attributable to noncontrolling common units is allocated based on their relative ownership percentage of the Operating Partnership during the reported period. The noncontrolling interest ownership percentage is determined by dividing the number of noncontrolling common units by the total number of common units outstanding. The issuance or redemption of additional shares of common stock or common units results in changes to the noncontrolling interest percentage as well as the total net assets of the Company. As a result, all equity transactions result in an allocation between equity and the noncontrolling interest in the Company’s consolidated balance sheets and statements of equity to account for the changes in the noncontrolling interest ownership percentage as well as the change in total net assets of the Company. Noncontrolling Interests in Consolidated Property Partnerships Noncontrolling interests in consolidated property partnerships represent the equity interests held by unrelated third parties in our three consolidated property partnerships (see Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements” and see Note 12 “Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements”). Noncontrolling interests in consolidated property partnerships are not redeemable and are presented as permanent equity in the Company's consolidated balance sheets. We account for the noncontrolling interests in consolidated property partnerships using the hypothetical liquidation at book value (“HLBV”) method to attribute the earnings or losses of the consolidated property partnerships between the controlling and noncontrolling interests. Under the HLBV method, the amounts reported as noncontrolling interests in consolidated property partnerships in the consolidated balance sheets represent the amounts the noncontrolling interests would hypothetically receive at each balance sheet reporting date under the liquidation provisions of the governing agreements assuming the net assets of the consoli

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Acquisitions	Acquisitions Operating Property Acquisitions During the year ended December 31, 2016 , we acquired the seven operating properties listed below in three transactions with unrelated third parties. We did not acquire any operating properties during the year ended December 31, 2015 . Property Date of Acquisition Number of Buildings Rentable Square Feet (unaudited) Occupancy as of December 31, 2016 (unaudited) Purchase Price (in millions) (1) 2016 Acquisitions 1290-1300 Terra Bella Avenue, Mountain View, CA (2) June 8, 2016 1 114,175 100.0% $ 55.4 8560-8590 West Sunset Blvd., West Hollywood, CA (3) December 7, 2016 4 178,699 87.5% 209.2 1701 Page Mill Rd. and 3150 Porter Dr., Palo Alto, CA (4) December 19, 2016 2 165,585 100.0% 130.0 Total (5) 7 458,459 $ 394.6 ________________________ (1) Excludes acquisition-related costs and non-lease related accrued liabilities assumed. Includes assumed unpaid leasing commissions and tenant improvements. (2) In connection with this acquisition, the Company assumed $0.2 million in accrued liabilities that are not included in the purchase price above. (3) This acquisition encompasses a 10-story office tower, three retail buildings, a four-level subterranean parking structure and three billboards. As of December 31, 2016 , this property was temporarily being held in a separate VIE to facilitate potential Section 1031 Exchanges. During January 2017, the Company closed out the Section 1031 Exchange related to this VIE. See Note 2 “Basis of Presentation and Significant Accounting Policies.” In connection with this acquisition, the Company assumed $0.1 million in accrued liabilities that are not included in the purchase price above. (4) In connection with this acquisition, the Company entered into a long-term ground lease expiring in December 2067. (5) The results of operations for the properties acquired during 2016 contributed $5.2 million and $1.7 million to revenue and net income from continuing operations, respectively, for the year ended December 31, 2016 . The related assets, liabilities and results of operations of the acquired properties are included in the consolidated financial statements as of the date of acquisition. The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the respective acquisition dates for our 2016 operating property acquisitions: Acquisitions Total 2016 Acquisitions (1) Assets (in thousands) Land and improvements $ 120,110 Buildings and improvements (2) 259,301 Deferred leasing costs and acquisition-related intangible assets (3) 33,529 Total assets acquired 412,940 Liabilities Accounts payable, accrued expenses and other liabilities 1,122 Deferred revenue and acquisition-related intangible liabilities (4) 18,050 Total liabilities assumed 19,172 Net assets and liabilities acquired $ 393,768 _______________ (1) The purchase price of the three acquisitions completed during the year ended December 31, 2016 were individually less than 5% and in aggregate less than 10% of the Company’s total assets as of December 31, 2015 . (2) Represents buildings, building improvements and tenant improvements. (3) Represents in-place leases (approximately $27.1 million with a weighted average amortization period of 3.9 years), above-market leases (approximately $0.6 million with weighted average amortization period of 15.8 years) and leasing commissions (approximately $5.8 million with a weighted average amortization period of 5.1 years). (4) Represents below-market leases (approximately $18.1 million with a weighted average amortization period of 8.4 years) Development Project Acquisitions On March 11, 2016 , we acquired an approximately 1.75 acre development site located at 610-620 Brannan Street in San Francisco, California from an unrelated third party. This land parcel is immediately adjacent to our Flower Mart project in the SOMA submarket of San Francisco. The acquisition was funded through $31.0 million in cash and the issuance of 867,701 common units in the Operating Partnership valued at approximately $48.0 million (see Note 14). In addition, the Company paid $2.4 million in seller transaction costs and recorded $4.7 million in accrued liabilities in connection with this acquisition. As of December 31, 2016 , the underlying assets were included as undeveloped land and construction in progress on our consolidated balance sheets. During the year ended December 31, 2015 we acquired the following undeveloped land sites listed below from unrelated third parties: Project Date of Acquisition City/Submarket Type Purchase Price (1) (in millions) 2015 Acquisitions 333 Dexter (2) February 13, 2015 Seattle, WA Land $ 49.5 100 Hooper (3) July 7, 2015 San Francisco, CA Land 78.0 Total $ 127.5 _______________ (1) See Note 18 “Commitments and Contingencies” for additional information on certain accrued liabilities for these acquisitions. (2) Acquisition comprised of four adjacent parcels in the South Lake Union submarket of Seattle, Washington located at 330 Dexter Avenue North, 333 Dexter Avenue North, 401 Dexter Avenue North, and 400 Aurora Avenue North. In connection with this acquisition, we also assumed $2.4 million in accrued liabilities and acquisition costs that are not included in the purchase price above. (3) Includes the land parcel located at 150 Hooper. In connection with this acquisition, we assumed $4.1 million in accrued liabilities and acquisition costs that are not included in the purchase price above.

Dispositions and Real Estate As

Dispositions and Real Estate Assets Held for Sale	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	Dispositions and Real Estate Assets Held for Sale Operating Property Dispositions The following table summarizes the operating properties sold during the years ended December 31, 2016 , 2015 and 2014 : Location Month of Disposition Number of Buildings Rentable Square Feet (unaudited) Sales Price (in millions) (1) 2016 Dispositions Torrey Santa Fe Properties (2) January 4 465,812 $ 262.3 4930, 4939 & 4955 Directors Place, San Diego, CA (3) July 2 136,908 49.0 Total 2016 Dispositions 6 602,720 $ 311.3 2015 Dispositions 15050 NE 36th Street, Redmond, WA April 1 122,103 $ 51.2 San Diego Properties - Tranches 1 and 2 (4) April/July 9 924,291 258.0 Total 2015 Dispositions 10 1,046,394 $ 309.2 2014 Dispositions (5) San Diego Properties, San Diego, CA (6) January 12 1,049,035 $ 294.7 9785 & 9791 Towne Centre Drive, San Diego, CA June 2 126,000 29.5 111 Pacifica, Irvine, CA September 1 67,496 15.1 4040 Civic Center Drive, San Rafael, CA October 1 130,237 34.9 999 Town & Country Road, Orange, CA December 1 98,551 25.3 Total 2014 Dispositions 17 1,471,319 $ 399.5 __________________ (1) Represents gross sales price before the impact of broker commissions and closing costs. (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe and 7555 Torrey Santa Fe. These properties were classified as held for sale at December 31, 2015 . (3) Includes two operating properties totaling 136,908 rentable square feet and a 7.0 acre undeveloped land parcel. (4) The San Diego Properties - Tranche 1 includes the following properties: 10770 Wateridge Circle, 6200 Greenwich Drive and 6220 Greenwich Drive. The San Diego Properties - Tranche 2 includes the following properties: 6260 Sequence Drive, 6290, Sequence Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive and 4921 Directors Place. (5) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, results of operations for properties disposed of subsequent of January 1, 2015 are presented in continuing operations because they did not represent strategic shifts. Properties disposed of prior to January 1, 2015 are presented in discontinued operations. (6) The San Diego Properties included the following properties: 10020 Pacific Mesa Boulevard, 6055 Lusk Avenue, 5010 and 5005 Wateridge Vista Drive, 15435 and 15445 Innovation Drive, and 15051, 15073, 15231, 15253, 15333 and 15378 Avenue of Science. These properties were held for sale as of December 31, 2013. The operations of the six properties sold during the year ended December 31, 2016 and ten properties sold during the year ended December 31, 2015 are presented in continuing operations for the years ended December 31, 2016 and December 31, 2015 , respectively. For the year ended December 31, 2014 , discontinued operations includes the income and gains on all of the properties sold in 2014 (see Note 2 “Basis of Presentation and Significant Accounting Policies” and Note 21 “Discontinued Operations” for additional information). The total gains on sales of the six properties sold during the year ended December 31, 2016 was $164.3 million . The total gains on sales of the ten properties sold during the year ended December 31, 2015 was $110.0 million . The total gains on sales of the 17 properties sold during the year ended December 31, 2014 was $121.9 million . Operating Properties Held for Sale As of December 31, 2016 and 2015 , the properties listed below were classified as held for sale. Properties Submarket Property Type Number of Buildings Rentable Square Feet (unaudited) 2016 Held for Sale 5717 Pacific Center Drive (1) Sorrento Mesa Office 1 67,995 2015 Held for Sale Torrey Santa Fe Properties (2)(3) Del Mar Office 4 465,812 __________________ (1) In January 2017, the Company completed the sale of this property for a total sales price of $12.1 million . (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe, and 7555 Torrey Santa Fe. (3) In January 2016, the Company completed the sale of these properties for a total sales price of $262.3 million . The major classes of assets and liabilities of the properties held for sale as of December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Real estate assets and other assets held for sale (in thousands) Land and improvements $ 2,693 $ 10,534 Buildings and improvements 10,500 144,716 Undeveloped land and construction in progress — 4,824 Total real estate held for sale 13,193 160,074 Accumulated depreciation and amortization (3,900 ) (46,191 ) Total real estate held for sale, net 9,293 113,883 Deferred rent receivables, net — 2,500 Deferred leasing costs and acquisition-related intangible assets, net — 1,115 Prepaid expenses and other assets, net 124 168 Real estate and other assets held for sale, net $ 9,417 $ 117,666 Liabilities and deferred revenue of real estate assets held for sale Secured debt $ — $ 561 Accounts payable, accrued expenses and other liabilities 56 2,497 Deferred revenue and acquisition-related intangible liabilities, net — 2,899 Rents received in advance and tenant security deposits — 1,586 Liabilities and deferred revenue of real estate assets held for sale $ 56 $ 7,543 Land Dispositions The following table summarizes the land dispositions completed during the years ended December 31, 2016 , 2015 and 2014 : Properties Submarket Month of Disposition Gross Site Acreage (unaudited) Sales Price (1) (in millions) 2016 Land Dispositions Carlsbad Oaks - Lot 7 (2) Carlsbad January 7.6 $ 4.5 Carlsbad Oaks - Lots 4 & 5 Carlsbad June 11.2 6.0 Carlsbad Oaks - Lot 8 Carlsbad June 13.2 8.9 Total 2016 Land Dispositions (3)(4) 32.0 $ 19.4 2015 Land Disposition 17150 Von Karman (4) Irvine January 8.5 $ 26.0 2014 Land Disposition 10850 Via Frontera (4) Rancho Bernardo April 21.0 $ 33.1 __________________ (1) Represents gross sales price before the impact of commissions and closing costs. (2) This land parcel was classified as held for sale as of December 31, 2015. (3) In connection with these land dispositions, $2.3 million of secured debt was assumed by the buyers. See Note 9 “Secured and Unsecured Debt of the Operating Partnership” for additional information. (4) The 2016 land dispositions resulted in a net loss on sales of $0.3 million and the 2015 and 2014 land dispositions resulted in gain on sales of $17.3 million and $3.5 million , respectively. Land Held for Sale We did not have any land classified as held for sale as of December 31, 2016 . As of December 31, 2015 , the following land parcel was classified as held for sale: Properties Submarket Gross Site Acreage (unaudited) Sales Price 2015 Held for Sale Carlsbad Oaks - Lot 7 (1) Carlsbad 7.6 $ 4.5 __________________ (1) During the year ended December 31, 2015, the Company recognized a loss relating to selling costs of approximately $0.2 million . Restricted Cash Related to Dispositions As of December 31, 2016 approximately $48.4 million of net proceeds related to the land and operating property dispositions during the year ended December 31, 2016 were temporarily being held at a qualified intermediary, at our direction, for the purpose of facilitating Section 1031 Exchanges. The cash proceeds were included in restricted cash on the consolidated balance sheet at December 31, 2016 . During January 2017, the Section 1031 Exchange was successfully completed and the cash proceeds were released from the qualified intermediary. We did not have any restricted cash related to dispositions or Section 1031 Exchanges as of December 31, 2015 . Discontinued Operations For the year ended December 31, 2014 , discontinued operations included the results of all properties sold in 2014, except for the operations deemed immaterial related to a June 2014 office property disposition. The following table summarizes the revenue and expense components that comprise income from discontinued operations for the year ended December 31, 2014 : 2014 (in thousands) Revenues: Rental income $ 7,206 Tenant reimbursements 278 Other property income 13 Total revenues 7,497 Expenses: Property expenses 2,171 Real estate taxes 692 Depreciation and amortization 2,061 Total expenses 4,924 Income from discontinued operations before net gain on dispositions of discontinued operations 2,573 Net gain on dispositions of discontinued operations 121,922 Total income from discontinued operations $ 124,495

Deferred Leasing Costs and Acqu

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net	Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net The following table summarizes our deferred leasing costs and acquisition-related intangible assets (acquired value of leasing costs, above-market operating leases, in-place leases and below-market ground lease obligation) and intangible liabilities (acquired value of below-market operating leases and above-market ground lease obligation) as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Deferred Leasing Costs and Acquisition-related Intangible Assets, net: (1) Deferred leasing costs $ 239,958 $ 205,888 Accumulated amortization (89,633 ) (72,745 ) Deferred leasing costs, net 150,325 133,143 Above-market operating leases 10,304 10,989 Accumulated amortization (6,933 ) (6,739 ) Above-market operating leases, net 3,371 4,250 In-place leases 94,813 72,639 Accumulated amortization (40,593 ) (33,810 ) In-place leases, net 54,220 38,829 Below-market ground lease obligation 490 490 Accumulated amortization (38 ) (29 ) Below-market ground lease obligation, net 452 461 Total deferred leasing costs and acquisition-related intangible assets, net $ 208,368 $ 176,683 Acquisition-related Intangible Liabilities, net: (2) Below-market operating leases $ 69,472 $ 53,502 Accumulated amortization (33,689 ) (27,074 ) Below-market operating leases, net 35,783 26,428 Above-market ground lease obligation 6,320 6,320 Accumulated amortization (525 ) (424 ) Above-market ground lease obligation, net 5,795 5,896 Total acquisition-related intangible liabilities, net $ 41,578 $ 32,324 _______________ (1) Excludes deferred leasing costs and acquisition-related intangible assets, net related to properties held for sale as of December 31, 2015 . (2) Included in deferred revenue and acquisition-related intangible liabilities, net in the consolidated balance sheets. The following table sets forth amortization related to deferred leasing costs and acquisition-related intangibles for the years ended December 31, 2016 , 2015 and 2014 , including amounts attributable to discontinued operations for the year ended December 31, 2014. Year Ended December 31, 2016 2015 2014 (in thousands) Deferred leasing costs (1) $ 28,639 $ 27,866 $ 27,555 Above-market operating leases (2) 1,509 2,532 5,303 In-place leases (1) 11,676 14,622 21,628 Below-market ground lease obligation (3) 8 8 8 Below-market operating leases (4) (8,674 ) (10,980 ) (13,238 ) Above-market ground lease obligation (5) (101 ) (101 ) (101 ) Total $ 33,057 $ 33,947 $ 41,155 _______________ (1) The amortization of deferred leasing costs and in-place leases is recorded to depreciation and amortization expense and the amortization of lease incentives is recorded as a reduction to rental income in the consolidated statements of operations for the periods presented. (2) The amortization of above-market operating leases is recorded as a decrease to rental income in the consolidated statements of operations for the periods presented. (3) The amortization of the below-market ground lease obligation is recorded as an increase to ground lease expense in the consolidated statements of operations for the periods presented. (4) The amortization of below-market operating leases is recorded as an increase to rental income in the consolidated statements of operations for the periods presented. (5) The amortization of the above-market ground lease obligation is recorded as a decrease to ground lease expense in the consolidated statements of operations for the periods presented. The following table sets forth the estimated annual amortization expense related to deferred leasing costs and acquisition-related intangibles as of December 31, 2016 for future periods: Year Deferred Leasing Costs Above-Market Operating Leases (1) In-Place Leases Below-Market Ground Lease Obligation (2) Below-Market Operating Leases (3) Above-Market Ground Lease Obligation (4) (in thousands) 2017 $ 29,190 $ 1,298 $ 18,366 $ 8 $ (10,633 ) $ (101 ) 2018 25,761 869 13,556 8 (9,116 ) (101 ) 2019 21,397 681 8,856 8 (6,519 ) (101 ) 2020 16,703 53 5,739 8 (3,676 ) (101 ) 2021 12,590 53 2,505 8 (1,031 ) (101 ) Thereafter 44,684 417 5,198 412 (4,808 ) (5,290 ) Total $ 150,325 $ 3,371 $ 54,220 $ 452 $ (35,783 ) $ (5,795 ) _______________ (1) Represents estimated annual amortization related to above-market operating leases. Amounts will be recorded as a decrease to rental income in the consolidated statements of operations. (2) Represents estimated annual amortization related to below-market ground lease obligations. Amounts will be recorded as an increase to ground lease expense in the consolidated statements of operations. (3) Represents estimated annual amortization related to below-market operating leases. Amounts will be recorded as an increase to rental income in the consolidated statements of operations. (4) Represents estimated annual amortization related to above-market ground lease obligations. Amounts will be recorded as a decrease to ground lease expense in the consolidated statements of operations.

Receivables

Receivables	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Receivables	Receivables Current Receivables, net Current receivables, net is primarily comprised of contractual rents and other lease-related obligations due from tenants. The balance consisted of the following as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Current receivables $ 15,172 $ 13,233 Allowance for uncollectible tenant receivables (1,712 ) (2,080 ) Current receivables, net $ 13,460 $ 11,153 Deferred Rent Receivables, net Deferred rent receivables, net consisted of the following as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Deferred rent receivables $ 220,501 $ 191,586 Allowance for deferred rent receivables (1,524 ) (1,882 ) Deferred rent receivables, net (1) $ 218,977 $ 189,704 __________________ (1) Excludes deferred rent receivables, net related to real estate held for sale as of December 31, 2015.

Prepaid Expenses and Other Asse

Prepaid Expenses and Other Assets, Net	12 Months Ended
	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Assets, Net	Prepaid Expenses and Other Assets, Net Prepaid expenses and other assets, net consisted of the following at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Furniture, fixtures and other long-lived assets, net $ 40,395 $ 11,324 Notes receivable (1) 19,439 3,056 Prepaid expenses 10,774 12,853 Total Prepaid Expenses and Other Assets, Net $ 70,608 $ 27,233 _______________ (1) Approximately $15.1 million of our notes receivables are secured by real estate.

Secured and Unsecured Debt of t

Secured and Unsecured Debt of the Company	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Secured and Unsecured Debt of the Company	Secured and Unsecured Debt of the Company In this Note 8, the “Company” refers solely to Kilroy Realty Corporation and not to any of our subsidiaries. The Company itself does not hold any indebtedness. All of our secured and unsecured debt is held directly by the Operating Partnership. The Company generally guarantees all the Operating Partnership’s unsecured debt obligations including the unsecured revolving credit facility, the $150.0 million unsecured term loan facility, the $39.0 million unsecured term loan, the 4.800% unsecured senior notes due in 2018, the 6.625% unsecured senior notes due in 2020, the 3.800% unsecured senior notes due in 2023, the 4.375% unsecured senior notes due in 2025, and the 4.250% unsecured senior notes due in 2029. At December 31, 2016 and 2015 , the Operating Partnership had $1.8 billion outstanding in total, including unamortized discounts and deferred financing costs, under these unsecured debt obligations. In addition, although the remaining $0.5 billion and $0.4 billion of the Operating Partnership’s debt as of December 31, 2016 and 2015 , respectively, is secured and non-recourse to the Company, the Company provides limited customary secured debt guarantees for items such as voluntary bankruptcy, fraud, misapplication of payments and environmental liabilities. Debt Covenants and Restrictions One of the covenants contained within the unsecured revolving credit facility, the unsecured term loan facility, and the unsecured term loan as discussed further below in Note 9 prohibits the Company from paying dividends in excess of: • 95% of the Operating Partnership’s consolidated funds from operations (as defined in the agreements governing the unsecured revolving credit facility, unsecured term loan facility and unsecured term loan) for such year; and • an amount which results in distributions to us (excluding any preferred partnership distributions to the extent the same have been deducted from consolidated funds from operations (as so defined) for such year) in an amount sufficient to permit us to pay dividends to our stockholders that we reasonably believe are necessary to (a) maintain our qualification as a REIT for federal and state income tax purposes and (b) avoid the payment of federal or state income or excise tax.

Secured and Unsecured Debt of22

Secured and Unsecured Debt of the Operating Partnership	12 Months Ended
	Dec. 31, 2016
Debt Instrument [Line Items]
Secured and Unsecured Debt of the Operating Partnership	Secured and Unsecured Debt of the Company In this Note 8, the “Company” refers solely to Kilroy Realty Corporation and not to any of our subsidiaries. The Company itself does not hold any indebtedness. All of our secured and unsecured debt is held directly by the Operating Partnership. The Company generally guarantees all the Operating Partnership’s unsecured debt obligations including the unsecured revolving credit facility, the $150.0 million unsecured term loan facility, the $39.0 million unsecured term loan, the 4.800% unsecured senior notes due in 2018, the 6.625% unsecured senior notes due in 2020, the 3.800% unsecured senior notes due in 2023, the 4.375% unsecured senior notes due in 2025, and the 4.250% unsecured senior notes due in 2029. At December 31, 2016 and 2015 , the Operating Partnership had $1.8 billion outstanding in total, including unamortized discounts and deferred financing costs, under these unsecured debt obligations. In addition, although the remaining $0.5 billion and $0.4 billion of the Operating Partnership’s debt as of December 31, 2016 and 2015 , respectively, is secured and non-recourse to the Company, the Company provides limited customary secured debt guarantees for items such as voluntary bankruptcy, fraud, misapplication of payments and environmental liabilities. Debt Covenants and Restrictions One of the covenants contained within the unsecured revolving credit facility, the unsecured term loan facility, and the unsecured term loan as discussed further below in Note 9 prohibits the Company from paying dividends in excess of: • 95% of the Operating Partnership’s consolidated funds from operations (as defined in the agreements governing the unsecured revolving credit facility, unsecured term loan facility and unsecured term loan) for such year; and • an amount which results in distributions to us (excluding any preferred partnership distributions to the extent the same have been deducted from consolidated funds from operations (as so defined) for such year) in an amount sufficient to permit us to pay dividends to our stockholders that we reasonably believe are necessary to (a) maintain our qualification as a REIT for federal and state income tax purposes and (b) avoid the payment of federal or state income or excise tax.
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Secured and Unsecured Debt of the Operating Partnership	Secured and Unsecured Debt of the Operating Partnership Secured Debt The following table sets forth the composition of our secured debt as of December 31, 2016 and 2015 : Annual Stated Interest Rate (1) GAAP Effective Rate (1)(2) Maturity Date December 31, Type of Debt 2016 2015 (in thousands) Mortgage note payable (3) 3.57% 3.57% December 2026 $ 170,000 $ — Mortgage note payable (4) 4.27% 4.27% February 2018 125,756 128,315 Mortgage note payable (4) 4.48% 4.48% July 2027 94,754 96,354 Mortgage note payable (4)(5) 6.05% 3.50% June 2019 82,443 85,890 Mortgage note payable (6) 7.15% 7.15% May 2017 1,215 3,987 Mortgage note payable (7) 6.51% 6.51% February 2017 — 65,563 Other (8) Various Various Various — 1,809 Total secured debt $ 474,168 $ 381,918 Unamortized Deferred Financing Costs (1,396 ) (1,083 ) Total secured debt, net $ 472,772 $ 380,835 ______________ (1) All interest rates presented are fixed-rate interest rates. (2) Represents the effective interest rate including the amortization of initial issuance discounts/premiums excluding the amortization of deferred financing costs. (3) This mortgage note payable was entered into in November 2016. (4) The secured debt and the related properties that secure the debt are held in a special purpose entity and the properties are not available to satisfy the debts and other obligations of the Company or the Operating Partnership. (5) As of December 31, 2016 and 2015 , the mortgage loan had unamortized debt premiums of $4.4 million and $6.2 million , respectively. (6) This mortgage note payable was repaid in February 2017 at par. (7) This mortgage note payable was repaid in December 2016 at par. (8) Balance of $1.8 million as of December 31, 2015 included public facility bonds that were assumed by the buyers in connection with sales of land during the year ended December 31, 2016 . The Operating Partnership’s secured debt was collateralized by operating properties with a combined net book value of approximately $570.6 million as of December 31, 2016 . Although our mortgage loans are secured and non-recourse to the Company and the Operating Partnership, the Company provides limited customary secured debt guarantees for items such as voluntary bankruptcy, fraud, misapplication of payments and environmental liabilities. As of December 31, 2016 , all of the Operating Partnership’s secured loans contained restrictions that would require the payment of prepayment penalties for the acceleration of outstanding debt. The mortgage notes payable are secured by deeds of trust on certain of our properties and the assignment of certain rents and leases associated with those properties. Unsecured Senior Notes In September 2015, the Operating Partnership issued $400.0 million of aggregate principal amount of unsecured senior notes in a registered public offering. The outstanding balance of the unsecured senior notes is included in unsecured debt, net of the unamortized balance of the initial issuance discount of $2.2 million , on our consolidated balance sheets. The unsecured senior notes, which are scheduled to mature on October 1, 2025 , require semi-annual interest payments each April and October based on a stated annual interest rate of 4.375% . The Company used the net proceeds to repay the $325.0 million 5.000% Unsecured Senior Notes upon maturity in November 2015 and for other general corporate purposes, including the repayment of debt and funding development expenditures. The following table summarizes the balance and significant terms of the registered unsecured senior notes issued by the Operating Partnership as of December 31, 2016 and 2015 : Net Carrying Amount Issuance date Maturity date Stated coupon rate Effective interest rate (1) 2016 2015 (in thousands) 4.375% Unsecured Senior Notes (2) September 2015 October 2025 4.375% 4.440% $ 400,000 $ 400,000 Unamortized discount and deferred financing costs (4,846 ) (5,400 ) Net carrying amount $ 395,154 $ 394,600 4.250% Unsecured Senior Notes (3) July 2014 August 2029 4.250% 4.350% $ 400,000 $ 400,000 Unamortized discount and deferred financing costs (6,696 ) (7,228 ) Net carrying amount $ 393,304 $ 392,772 3.800% Unsecured Senior Notes (4) January 2013 January 2023 3.800% 3.804% $ 300,000 $ 300,000 Unamortized discount and deferred financing costs (1,656 ) (1,931 ) Net carrying amount $ 298,344 $ 298,069 4.800% Unsecured Senior Notes (4)(5) July 2011 July 2018 4.800% 4.827% $ 325,000 $ 325,000 Unamortized discount and deferred financing costs (767 ) (1,251 ) Net carrying amount $ 324,233 $ 323,749 6.625% Unsecured Senior Notes (6) May 2010 June 2020 6.625% 6.743% $ 250,000 $ 250,000 Unamortized discount and deferred financing costs (1,868 ) (2,414 ) Net carrying amount $ 248,132 $ 247,586 Total Unsecured Senior Notes, Net $ 1,659,167 $ 1,656,776 ________________________ (1) Represents the effective interest rate including the amortization of initial issuance discounts, excluding the amortization of deferred financing costs. (2) Interest on these notes is payable semi-annually in arrears on April 1st and October 1st of each year. (3) Interest on these notes is payable semi-annually in arrears on February 15th and August 15th of each year. (4) Interest on these notes is payable semi-annually in arrears on January 15th and July 15th of each year. (5) In October 2015, certain common limited partners in the Operating Partnership that previously contributed their interests in the property at 6255 W. Sunset Blvd., Los Angeles, California to the Operating Partnership entered into an agreement with the Company. Pursuant to this agreement, such common limited partners will reimburse the Company for a portion of any amounts the Company may be required to pay pursuant to its guarantee of the Operating Partnership's 4.800% Senior Notes due 2018 or that the Company may otherwise become required to pay under applicable law with respect to such notes. (6) Interest on these notes is payable semi-annually in arrears on June 1st and December 1st of each year. Unsecured Senior Notes - Private Placement On September 14, 2016, the Operating Partnership entered into a Note Purchase Agreement in a private placement (the “Note Purchase Agreement”), in connection with the issuance and sale of $175.0 million principal amount of the Operating Partnership’s 3.35% Senior Notes, Series A, due February 17, 2027 (the “Series A Notes”), and $75.0 million principal amount of the Operating Partnership’s 3.45% Senior Notes, Series B, due February 17, 2029 (the “Series B Notes” and, together with the Series A Notes, the “Series A and B Notes”). Under the delayed draw option of the Series A and B Notes, the Operating Partnership is required to issue $175.0 million principal amount of its Series A Notes and $75.0 million principal amount of its Series B Notes by February 17, 2017. As of December 31, 2016 , there were no amounts issued or outstanding under the Series A and B Notes. The Series A Notes mature on February 17, 2027, and the Series B notes mature on February 17, 2029, unless earlier redeemed or prepaid pursuant to the terms of the Note Purchase Agreement. Interest on the Notes is payable semi-annually in arrears on February 17 and August 17 of each year beginning February 17, 2017. The Operating Partnership may, at its option and upon notice to the purchasers of the Series A and B Notes, prepay at any time all, or from time to time any part of the Series A and B Notes then outstanding (in an amount not less than 5% of the aggregate principal amount of the Series A and B Notes then outstanding in the case of a partial prepayment), at 100% of the principal amount so prepaid, plus the make-whole amount determined for the prepayment date with respect to such principal amount as set forth in the Note Purchase Agreement. In connection with the issuance of the Series A and B Notes, the Company will enter into an agreement whereby it will guarantee the payment by the Operating Partnership of all amounts due with respect to the Series A and B Notes and the performance by the Operating Partnership of its obligations under the Note Purchase Agreement. Unsecured Revolving Credit Facility and Unsecured Term Loan Facility The following table summarizes the balance and terms of our unsecured revolving credit facility as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Outstanding borrowings $ — $ — Remaining borrowing capacity 600,000 600,000 Total borrowing capacity (1) $ 600,000 $ 600,000 Interest rate (2) 1.82 % 1.48 % Facility fee-annual rate (3) 0.200% Maturity date July 2019 _______________ (1) We may elect to borrow, subject to bank approval and obtaining commitments for any additional borrowing capacity, up to an additional $311.0 million under an accordion feature under the terms of the unsecured revolving credit facility and unsecured term loan facility. (2) The interest rate on our unsecured revolving credit facility is based on an annual rate of LIBOR plus 1.050% . (3) Our facility fee is paid on a quarterly basis and is calculated based on the total borrowing capacity. In addition to the facility fee, we incurred debt origination and legal costs. As of December 31, 2016 and 2015 , $3.3 million and $4.6 million of deferred financing costs remained to be amortized through the maturity date of our unsecured revolving credit facility, which are included in prepaid expenses and other assets, net on our consolidated balance sheets. The Company intends to borrow amounts under the unsecured revolving credit facility from time to time for general corporate purposes, to fund potential acquisitions, to finance development and redevelopment expenditures and to potentially repay long-term debt. The following table summarizes the balance and terms of our term loan facility, which is included in our unsecured debt, as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Outstanding borrowings (1) $ 150,000 $ 150,000 Interest rate (2) 1.85 % 1.40 % Maturity date July 2019 _______________ (1) As of December 31, 2016 and December 31, 2015 , $0.7 million and $0.9 million of unamortized deferred financing costs, respectively, remained to be amortized through the maturity date of our unsecured term loan facility. (2) Our unsecured term loan facility interest rate was calculated based on an annual rate of LIBOR plus 1.150% . Additionally, the Company has a $39.0 million unsecured term loan outstanding with an annual interest rate of LIBOR plus 1.150% as of December 31, 2016 and 2015 , that matures in July 2019. As of December 31, 2016 and 2015 , $0.2 million of unamortized deferred financing costs remained to be amortized through the maturity date of our unsecured term loan. Debt Covenants and Restrictions The unsecured revolving credit facility, the unsecured term loan facility, the unsecured term loan, the unsecured senior notes, the Series A and B Notes and certain other secured debt arrangements contain covenants and restrictions requiring us to meet certain financial ratios and reporting requirements. Some of the more restrictive financial covenants include a maximum ratio of total debt to total asset value, a minimum fixed-charge coverage ratio, a minimum unsecured debt ratio and a minimum unencumbered asset pool debt service coverage ratio. Noncompliance with one or more of the covenants and restrictions could result in the full principal balance of the associated debt becoming immediately due and payable. We believe we were in compliance with all of our debt covenants as of December 31, 2016 and 2015 . Debt Maturities The following table summarizes the stated debt maturities and scheduled amortization payments as of December 31, 2016 : Year (in thousands) 2017 $ 7,286 2018 451,669 2019 265,309 2020 255,137 2021 5,342 Thereafter 1,349,023 Total aggregate principal value (1)(2) $ 2,333,766 ________________________ (1) Includes gross principal balance of outstanding debt before the effect of the following at December 31, 2016 : $11.5 million of unamortized deferred financing costs, $6.6 million of unamortized discounts for the unsecured senior notes and $4.4 million of unamortized premiums for the secured debt. (2) Excludes the Series A and B Notes issuable pursuant to the Note Purchase Agreement entered into in September 2016 as no Series A or B Notes were issued and outstanding under these notes as of December 31, 2016 . 4.25% Exchangeable Senior Notes due 2014 The Company repaid its $172.5 million 4.25% Exchangeable Notes due November 2014 (the “ 4.25% Exchangeable Notes”) upon maturity in November 2014. The unamortized discount on the 4.25% Exchangeable Notes was accreted as additional interest expense from the date of issuance through the maturity date. The following table summarizes the total interest expense attributable to the 4.25% Exchangeable Notes prior to maturity in November 2014, based on the effective interest rates, before the effect of capitalized interest, for the year ended December 31, 2014 : Year Ended December 31, 2014 Contractual interest payments $ 5,608 Amortization of discount 3,769 Interest expense attributable to the 4.25% Exchangeable Notes $ 9,377 For the respective reporting periods noted below, which preceding maturity of the 4.25% Exchangeable Notes on November 15, 2014, the per share average trading price of the Company's common stock on the NYSE was higher than the $35.93 exchange price for the 4.25% Exchangeable Notes, as presented in the table below. See Note 22 “Net Income Available to Common Stockholders Per Share of the Company” and Note 23 “Net Income Available to Common Unitholders Per Unit of the Operating Partnership” for a discussion of the impact of the 4.25% Exchangeable Notes on our diluted earnings per share and unit calculations for the year ended December 31, 2014. Period Ended November 15, 2014 (1) Per share average trading price of the Company's common stock $ 60.04 _______________ (1) Represents the maturity date of the 4.25% Exchangeable Notes. Capitalized Interest and Loan Fees The following table sets forth gross interest expense reported in continuing operations, including debt discount/premium and deferred financing cost amortization, net of capitalized interest, for the years ended December 31, 2016 , 2015 and 2014 . The interest expense capitalized was recorded as a cost of development and redevelopment, and increased the carrying value of undeveloped land and construction in progress. Year Ended December 31, 2016 2015 2014 (in thousands) Gross interest expense $ 105,263 $ 109,647 $ 114,661 Capitalized interest (49,460 ) (51,965 ) (47,090 ) Interest expense $ 55,803 $ 57,682 $ 67,571

Deferred Revenue and Acquisitio

Deferred Revenue and Acquisition Related Liabilities, net	12 Months Ended
	Dec. 31, 2016
Deferred Revenue Disclosure [Abstract]
Deferred Revenue and Acquisition Related Liabilities, net	Deferred Revenue and Acquisition Related Liabilities, net Deferred revenue and acquisition-related liabilities, net consisted of the following at December 31, 2016 and 2015 : December 31, 2016 2015 (in thousands) Deferred revenue related to tenant-funded tenant improvements (1) $ 99,489 $ 90,825 Other deferred revenue 9,293 5,007 Acquisition-related intangible liabilities, net (2) 41,578 32,324 Total $ 150,360 $ 128,156 ________________________ (1) Excludes deferred revenue related to tenant-funded tenant improvements related to properties held for sale at December 31, 2015 . (2) See Note 2 “Basis of Presentation and Significant Accounting Policies” and Note 5 “Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net” for additional information. Deferred Revenue Related to Tenant-funded Tenant Improvements During the years ended December 31, 2016 , 2015 , and 2014 , $13.2 million , $13.3 million and $11.0 million , respectively, of deferred revenue related to tenant-funded tenant improvements (including discontinued operations for the year ended December 31, 2014 ) was amortized and recognized as rental income. The following is the estimated amortization of deferred revenue related to tenant-funded tenant improvements as of December 31, 2016 for the next five years and thereafter: Year Ending (in thousands) 2017 $ 14,453 2018 13,891 2019 12,349 2020 11,767 2021 10,524 Thereafter 36,505 Total $ 99,489

Noncontrolling Interests on the

Noncontrolling Interests on the Company's Consolidated Financial Statements	12 Months Ended
	Dec. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling Interests on the Company's Consolidated Financial Statements	Noncontrolling Interests on the Company’s Consolidated Financial Statements Common Units of the Operating Partnership The Company owned a 97.5% and 98.1% common general partnership interest in the Operating Partnership as of December 31, 2016 and 2015 , respectively. The remaining 2.5% and 1.9% common limited partnership interest as of December 31, 2016 and 2015 , respectively, was owned by non-affiliated investors and certain of our executive officers and directors in the form of noncontrolling common units. There were 2,381,543 and 1,764,775 common units outstanding held by these investors, executive officers and directors as of December 31, 2016 and 2015 , respectively. The increase in the common units from December 31, 2015 to December 31, 2016 was attributable to 867,701 common units issued in connection with an acquisition (see Note 3), partially offset by unit redemptions. The noncontrolling common units may be redeemed by unitholders for cash. Except under certain circumstances, we, at our option, may satisfy the cash redemption obligation with shares of the Company’s common stock on a one-for-one basis. If satisfied in cash, the value for each noncontrolling common unit upon redemption is the amount equal to the average of the closing quoted price per share of the Company’s common stock, par value $0.01 per share, as reported on the NYSE for the ten trading days immediately preceding the applicable redemption date. The aggregate value upon redemption of the then-outstanding noncontrolling common units was $174.9 million and $112.0 million as of December 31, 2016 and 2015 , respectively. This redemption value does not necessarily represent the amount that would be distributed with respect to each noncontrolling common unit in the event of our termination or liquidation. In the event of our termination or liquidation, it is expected in most cases that each common unit would be entitled to a liquidating distribution equal to the liquidating distribution payable in respect of each share of the Company’s common stock. Noncontrolling Interest in Consolidated Property Partnerships On August 30, 2016, the Operating Partnership entered into agreements with Norges Bank Real Estate Management (“NBREM”) whereby NBREM invested, through two REIT subsidiaries, in two existing companies that owned the Company’s 100 First Street and 303 Second Street office properties located in San Francisco, California. Based on a gross valuation of the two properties of approximately $1.2 billion , NBREM contributed a total of $452.9 million , for a 44% common equity interest in the companies, which is net of approximately $55.3 million of its proportionate share of the existing mortgage debt on 303 Second Street. The transaction was structured with a staggered closing. On August 30, 2016, the first tranche of the transaction closed and NBREM contributed $191.4 million plus a working capital contribution of $2.1 million for a 44% common ownership interest in 100 First LLC. On November 30, 2016, the second tranche of the transaction closed and NBREM contributed $261.5 million , which was net of its proportionate share of the existing mortgage debt secured by the 303 Second Street property of approximately $55.3 million , plus a working capital contribution of $2.9 million for a 44% common ownership interest in 303 Second LLC. The transactions did not meet the criteria to qualify as sales of real estate because the Company continues to effectively control the properties and therefore continued to account for the 100 First Street and 303 Second Street office properties on a consolidated basis in its financial statements. At formation, the Company accounted for the transactions as equity transactions and recognized noncontrolling interests in its consolidated balance sheets totaling approximately $124.5 million , which was equal to 44% of the aggregate net asset value of 100 First LLC and 303 Second LLC immediately prior to the transactions (which was net of NBREM’s 44% share of the existing mortgage debt of $55.3 million ) plus an additional $5.0 million working capital contribution made by NBREM. The amount of NBREM’s total contribution not recognized as noncontrolling interest, net of transaction costs, was approximately $329.0 million . This amount was not reflected as a gain on sale of operating properties in the Company’s consolidated statements of operations and instead was reflected as an increase in additional paid-in capital and partners’ capital in the Company’s and the Operating Partnership’s consolidated balance sheets, respectively. Transfers of less than 50% of an entity ownership interest are normally not subject to certain tax assessments in California and therefore the Company believes that the two tranches of the transaction do not meet the statutory requirements for such tax assessments. If the taxing authority attempted to assess such tax assessments on the transactions, the Company estimates it could incur additional taxes of up to $10.9 million and $18.0 million for the first and second tranches of the transaction, respectively, plus potential penalties and interest. In connection with the transaction, the Company provides customary property management, leasing and construction management services for both properties. 100 First Street is a 467,095 square foot office tower, and 303 Second Street is a 740,047 square foot office property, both located in the South of Market submarket in San Francisco, California. The noncontrolling interests in 100 First LLC and 303 Second LLC as of December 31, 2016 was $124.3 million which is recognized in noncontrolling interests in consolidated property partnerships on the Company's consolidated balance sheets. The remaining amount of noncontrolling interests in consolidated property partnerships represents the third party equity interest in Redwood LLC. This noncontrolling interest was $6.4 million and $6.5 million as of December 31, 2016 and December 31, 2015 , respectively. Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements Consolidated Property Partnerships On August 30, 2016, the Operating Partnership entered into agreements with NBREM whereby NBREM invested, through two REIT subsidiaries, in two existing companies that owned the Company’s 100 First Street and 303 Second Street office properties located in San Francisco, California. Based on a gross valuation of the two properties of approximately $1.2 billion , NBREM contributed a total of $452.9 million for a 44% common equity interest in the companies, which is net of approximately $55.3 million of its proportionate share of the existing mortgage debt. Refer to Note 11 for additional information regarding these transactions.

Noncontrolling Interests on t25

Noncontrolling Interests on the Operating Partnership's Consolidated Financial Statements	12 Months Ended
	Dec. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements	Noncontrolling Interests on the Company’s Consolidated Financial Statements Common Units of the Operating Partnership The Company owned a 97.5% and 98.1% common general partnership interest in the Operating Partnership as of December 31, 2016 and 2015 , respectively. The remaining 2.5% and 1.9% common limited partnership interest as of December 31, 2016 and 2015 , respectively, was owned by non-affiliated investors and certain of our executive officers and directors in the form of noncontrolling common units. There were 2,381,543 and 1,764,775 common units outstanding held by these investors, executive officers and directors as of December 31, 2016 and 2015 , respectively. The increase in the common units from December 31, 2015 to December 31, 2016 was attributable to 867,701 common units issued in connection with an acquisition (see Note 3), partially offset by unit redemptions. The noncontrolling common units may be redeemed by unitholders for cash. Except under certain circumstances, we, at our option, may satisfy the cash redemption obligation with shares of the Company’s common stock on a one-for-one basis. If satisfied in cash, the value for each noncontrolling common unit upon redemption is the amount equal to the average of the closing quoted price per share of the Company’s common stock, par value $0.01 per share, as reported on the NYSE for the ten trading days immediately preceding the applicable redemption date. The aggregate value upon redemption of the then-outstanding noncontrolling common units was $174.9 million and $112.0 million as of December 31, 2016 and 2015 , respectively. This redemption value does not necessarily represent the amount that would be distributed with respect to each noncontrolling common unit in the event of our termination or liquidation. In the event of our termination or liquidation, it is expected in most cases that each common unit would be entitled to a liquidating distribution equal to the liquidating distribution payable in respect of each share of the Company’s common stock. Noncontrolling Interest in Consolidated Property Partnerships On August 30, 2016, the Operating Partnership entered into agreements with Norges Bank Real Estate Management (“NBREM”) whereby NBREM invested, through two REIT subsidiaries, in two existing companies that owned the Company’s 100 First Street and 303 Second Street office properties located in San Francisco, California. Based on a gross valuation of the two properties of approximately $1.2 billion , NBREM contributed a total of $452.9 million , for a 44% common equity interest in the companies, which is net of approximately $55.3 million of its proportionate share of the existing mortgage debt on 303 Second Street. The transaction was structured with a staggered closing. On August 30, 2016, the first tranche of the transaction closed and NBREM contributed $191.4 million plus a working capital contribution of $2.1 million for a 44% common ownership interest in 100 First LLC. On November 30, 2016, the second tranche of the transaction closed and NBREM contributed $261.5 million , which was net of its proportionate share of the existing mortgage debt secured by the 303 Second Street property of approximately $55.3 million , plus a working capital contribution of $2.9 million for a 44% common ownership interest in 303 Second LLC. The transactions did not meet the criteria to qualify as sales of real estate because the Company continues to effectively control the properties and therefore continued to account for the 100 First Street and 303 Second Street office properties on a consolidated basis in its financial statements. At formation, the Company accounted for the transactions as equity transactions and recognized noncontrolling interests in its consolidated balance sheets totaling approximately $124.5 million , which was equal to 44% of the aggregate net asset value of 100 First LLC and 303 Second LLC immediately prior to the transactions (which was net of NBREM’s 44% share of the existing mortgage debt of $55.3 million ) plus an additional $5.0 million working capital contribution made by NBREM. The amount of NBREM’s total contribution not recognized as noncontrolling interest, net of transaction costs, was approximately $329.0 million . This amount was not reflected as a gain on sale of operating properties in the Company’s consolidated statements of operations and instead was reflected as an increase in additional paid-in capital and partners’ capital in the Company’s and the Operating Partnership’s consolidated balance sheets, respectively. Transfers of less than 50% of an entity ownership interest are normally not subject to certain tax assessments in California and therefore the Company believes that the two tranches of the transaction do not meet the statutory requirements for such tax assessments. If the taxing authority attempted to assess such tax assessments on the transactions, the Company estimates it could incur additional taxes of up to $10.9 million and $18.0 million for the first and second tranches of the transaction, respectively, plus potential penalties and interest. In connection with the transaction, the Company provides customary property management, leasing and construction management services for both properties. 100 First Street is a 467,095 square foot office tower, and 303 Second Street is a 740,047 square foot office property, both located in the South of Market submarket in San Francisco, California. The noncontrolling interests in 100 First LLC and 303 Second LLC as of December 31, 2016 was $124.3 million which is recognized in noncontrolling interests in consolidated property partnerships on the Company's consolidated balance sheets. The remaining amount of noncontrolling interests in consolidated property partnerships represents the third party equity interest in Redwood LLC. This noncontrolling interest was $6.4 million and $6.5 million as of December 31, 2016 and December 31, 2015 , respectively. Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements Consolidated Property Partnerships On August 30, 2016, the Operating Partnership entered into agreements with NBREM whereby NBREM invested, through two REIT subsidiaries, in two existing companies that owned the Company’s 100 First Street and 303 Second Street office properties located in San Francisco, California. Based on a gross valuation of the two properties of approximately $1.2 billion , NBREM contributed a total of $452.9 million for a 44% common equity interest in the companies, which is net of approximately $55.3 million of its proportionate share of the existing mortgage debt. Refer to Note 11 for additional information regarding these transactions.

Stockholders' Equity of the Com

Stockholders' Equity of the Company	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Stockholders' Equity of the Company	Stockholders’ Equity of the Company Common Stock At-The-Market Stock Offering Programs Under our current at-the-market stock offering program, which commenced in December 2014, we may offer and sell shares of our common stock having an aggregate gross sales price of up to $300.0 million from time to time in “at-the-market” offerings. Since commencement of the program through December 31, 2016 , we have sold 2,459,165 shares of common stock having an aggregate gross sales price of $182.4 million . As of December 31, 2016 , shares of common stock having an aggregate gross sales price of up to $117.6 million remain available to be sold under this program. Actual future sales will depend upon a variety of factors, including but not limited to market conditions, the trading price of the Company’s common stock and our capital needs. We have no obligation to sell the remaining shares available for sale under this program. The following table sets forth information regarding sales of our common stock under our at-the-market offering programs for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in millions, except share data) Shares of common stock sold during the period 451,398 1,866,267 1,599,123 Aggregate gross proceeds $ 32.3 $ 140.1 $ 104.7 Aggregate net proceeds after selling commissions $ 31.9 $ 138.2 $ 103.1 The proceeds from sales were used to fund acquisitions, development expenditures and general corporate purposes including repayment of borrowings under the unsecured revolving credit facility. Common Stock Issuance In July 2015, the Company completed the sale and issuance of 3,733,766 shares of its common stock at a price of $66.19 per share for aggregate gross proceeds of $249.8 million and aggregate net proceeds after offering costs of $249.6 million through a registered direct placement with an institutional investor. In October 2014, the Company issued 351,476 shares of its common stock valued at approximately $21.6 million to partially fund a development acquisition (see Note 3 “Acquisitions” for additional information). Common Stock Repurchases On February 23, 2016, the Company’s Board of Directors approved a 4,000,000 share increase to the Company’s existing share repurchase program bringing the total current repurchase authorization to 4,988,025 shares. In March 2016, the Company repurchased 52,199 shares of common stock at a weighted average price of $55.45 per share of common stock for $2.9 million . As of December 31, 2016 , 4,935,826 shares remain eligible for repurchase under the Company’s share repurchase program. The Company did not repurchase shares of common stock under this program during the years ended December 31, 2015 or 2014 . Accrued Dividends and Distributions On December 13, 2016, the Company’s Board of Directors declared a special cash dividend of $1.90 per share of common stock and a regular quarterly cash dividend of $0.375 per share of common stock payable on January 13, 2017 to stockholders of record on December 30, 2016. The following tables summarize accrued dividends and distributions for the noted outstanding shares of common stock, preferred stock, and noncontrolling units as of December 31, 2016 and 2015 : December 31, 2016 2015 (in thousands) Dividends and Distributions payable to: Common stockholders $ 212,074 $ 32,291 Noncontrolling common unitholders of the Operating Partnership 5,418 618 RSU holders (1) 3,158 427 Total accrued dividends and distribution to common stockholders and noncontrolling unitholders 220,650 33,336 Preferred stockholders 1,656 1,656 Total accrued dividends and distributions $ 222,306 $ 34,992 ______________________ (1) The amount includes the value of the dividend equivalents that will be paid with additional RSUs (see Note 15 “Share-Based Compensation” for additional information). December 31, 2016 2015 Outstanding Shares and Units: Common stock (1) 93,219,439 92,258,690 Noncontrolling common units 2,381,543 1,764,775 RSUs (2) 1,395,189 1,269,809 Series G Preferred stock 4,000,000 4,000,000 Series H Preferred stock 4,000,000 4,000,000 ______________________ (1) The amount includes nonvested shares. (2) The amount includes nonvested RSUs. Does not include the 659,051 and 425,452 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2016 and 2015 , respectively. 6.875% Series G and 6.375% Series H Cumulative Redeemable Preferred Stock The Company has the option to redeem the 4,000,000 shares of its 6.875% Series G Cumulative Redeemable Preferred Stock ("Series G Preferred Stock") and the 4,000,000 shares of its 6.375% Series H Cumulative Redeemable Preferred Stock ("Series H Preferred Stock"), on or after March 27, 2017 and August 15, 2017, respectively, in whole or in part at any time or from time to time, by payment of $25.00 per share in cash, totaling $200.0 million plus any accumulated, accrued and unpaid distributions through the date of redemption. Depending on various factors, including but not limited to market conditions, we may redeem all or part of the outstanding Series G and Series H Preferred Stock on or after their stated redemption dates. Upon redemption of all outstanding Series G and Series H Preferred Stock, we would incur an associated non-cash charge of $7.6 million as a reduction to net income available to common stockholders for the related original issuance costs.

Partners' Capital of the Operat

Partners' Capital of the Operating Partnership	12 Months Ended
	Dec. 31, 2016
Partners' Capital [Abstract]
Partners' Capital of the Operating Partnership	Partners' Capital of the Operating Partnership Common Units At-The-Market Stock Offering Program During the years ended December 31, 2016 , 2015 and 2014 , the Company utilized its at-the-market stock offering programs to issue shares of common stock (see Note 13 “Stockholders’ Equity of the Company” for additional information). The net offering proceeds and property acquired using net offering proceeds were contributed by the Company to the Operating Partnership in exchange for common units for the years ended December 31, 2016 , 2015 and 2014 are as follows: Year Ended December 31, 2016 2015 2014 (in millions, except share and per share data) Shares of common stock contributed by the Company 451,398 1,866,267 1,599,123 Common units exchanged for shares of common stock by the Company 451,398 1,866,267 1,599,123 Aggregate gross proceeds $ 32.3 $ 140.1 $ 104.7 Aggregate net proceeds after selling commissions $ 31.9 $ 138.2 $ 103.1 Issuance of Common Units In March 2016, the Operating Partnership issued 867,701 common units in connection with a development acquisition (see Note 3 “Acquisitions”). Each common unit was valued at $55.36 , which was based on a trailing ten-day average of the closing quoted price per share of the Company’s common stock, par value $.01 per share, as reported on the NYSE, as calculated in accordance with the Partnership Agreement. In July 2015, the Company completed the sale and issuance of 3,733,766 shares of its common stock at a price of $66.19 per share for aggregate gross proceeds of $249.8 million and aggregate net proceeds after offering costs of $249.6 million through a registered direct placement with an institutional investor (see Note 13 “Stockholders’ Equity of the Company” for additional information). The net offering proceeds were contributed by the Company to the Operating Partnership in exchange for 3,733,766 common units. In October 2014, the Company issued 351,476 shares of its common stock to partially fund $21.6 million of a development acquisition (see Note 13 “Stockholders’ Equity of the Company” for additional information). The development acquisition property was contributed by the Company to the Operation Partnership in exchange for 351,476 common units. Common Units Outstanding The following table sets forth the number of common units held by the Company and the number of common units held by non-affiliated investors and certain of our executive officers and directors in the form of noncontrolling common units as well as the ownership interest held on each respective date: December 31, 2016 December 31, 2015 Company owned common units in the Operating Partnership 93,219,439 92,258,690 Company owned general partnership interest 97.5 % 98.1 % Noncontrolling common units of the Operating Partnership 2,381,543 1,764,775 Ownership interest of noncontrolling interest 2.5 % 1.9 % For a further discussion of the noncontrolling common units during the years ended December 31, 2016 and 2015 , refer to Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements.” Accrued Distributions The following tables summarize accrued distributions for the noted common and preferred units as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Distributions payable to: General partner $ 212,074 $ 32,291 Common limited partners 5,418 618 RSU holders (1) 3,158 427 Total accrued distributions to common unitholders 220,650 33,336 Preferred unitholders 1,656 1,656 Total accrued distributions $ 222,306 $ 34,992 ______________________ (1) The amount includes the value of the dividend equivalents that will be paid with additional RSUs (see Note 15 “Share-Based Compensation” for additional information). December 31, 2016 December 31, 2015 Outstanding Units: Common units held by the general partner 93,219,439 92,258,690 Common units held by the limited partners 2,381,543 1,764,775 RSUs (1) 1,395,189 1,269,809 Series G Preferred units 4,000,000 4,000,000 Series H Preferred units 4,000,000 4,000,000 ______________________ (1) Does not include the 659,051 and 425,452 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2016 and 2015 , respectively.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation Stockholder Approved Share-Based Incentive Compensation Plan As of December 31, 2016 , we maintained one share-based incentive compensation plan, the Kilroy Realty 2006 Incentive Award Plan, as amended (the “2006 Plan”). At our annual meeting of stockholders on May 21, 2015, stockholders approved an amendment and restatement of the 2006 Plan, which included an increase in the maximum number of shares that may be issued or awarded under the 2006 Plan to 8,320,000 shares. As of December 31, 2016 , 1.3 million shares were available for grant under the 2006 Plan. The calculation of shares available for grant is presented after taking into account a reserve for a sufficient number of shares to cover the vesting and payment of 2006 Plan awards that were outstanding on that date, including performance-based vesting awards at (i) levels actually achieved for the performance conditions (as defined below) and (ii) at target levels for the market conditions (as defined below) applicable to these awards. The Executive Compensation Committee ( the “Compensation Committee”) of the Company's Board of Directors may grant the following share-based awards to eligible individuals, as provided under the 2006 Plan: incentive stock options, nonqualified stock options, restricted stock (nonvested shares), stock appreciation rights, performance shares, performance stock units, dividend equivalents, stock payments, deferred stock, restricted stock units (“RSUs”), profit interest units, performance bonus awards, performance-based awards and other incentive awards. For each award granted under our share-based incentive compensation programs, the Operating Partnership simultaneously issues to the Company a number of common units equal to the number of shares of common stock ultimately paid by the Company in respect of such awards. Stock Award Deferral Program We have a Stock Award Deferral Program (the “RSU Program”) under the 2006 Plan. Under the RSU Program, participants may defer receipt of awards of nonvested shares that may be granted by electing to receive an equivalent number of RSUs in lieu of such nonvested shares, or defer payment of RSU awards. Each RSU represents the right to receive one share of our common stock in the future and is subject to the same vesting conditions that would have applied if the award had been issued in nonvested shares. RSUs carry with them the right to receive dividend equivalents such that participants receive additional RSUs at the time dividends are paid equal to the value of the dividend earned on the shares underlying the participant’s RSUs. The dividend equivalents earned vest based on terms specified under the related RSU award agreement. Shares issued upon settlement of vested RSUs, including RSUs paid on dividend equivalents, are distributed in a single lump sum distribution upon the earlier of (1) the date specified by the participant when the election is made or (2) occurrence of certain other events specified under the RSU program. Share-Based Compensation Programs The Compensation Committee has historically awarded nonvested shares and RSUs under the share-based compensation programs described below. These share-based awards were valued based on the quoted closing share price of the Company’s common stock on the NYSE on the applicable grant date. Prior to 2014, the Compensation Committee awarded annual long-term equity awards based primarily on the prior year’s performance, however, starting in January 2014, such annual awards have been granted as an incentive for the year in which the awards were granted and subsequent years. Executive Officer and Key Employee Share-Based Compensation Programs The Compensation Committee has annually approved compensation programs that include the potential issuance of share-based awards to our executive officers and other key employees as part of their annual and long-term incentive compensation. The share-based awards are generally issued in the first quarter after the end of our prior fiscal year. The share-based awards generally have a service vesting period, which has historically ranged from one to five years, depending on the type of award. Non-Employee Board Member Share-Based Compensation Program The Board of Directors awards nonvested shares or nonvested RSUs to non-employee board members on an annual basis as part of such board members’ annual compensation and to newly elected non-employee board members in accordance with our Board of Directors compensation program. The share-based awards are generally issued in the second quarter, and the individual share awards vest in equal annual installments over the applicable service vesting period, which will be one year for the annual non-employee board awards and four years for the awards relating to newly elected non-employee board members. 2016 and 2015 Share-Based Compensation Grants On January 28, 2016 (the “2016 RSU Grant Date”), the Compensation Committee of the Company’s Board of Directors awarded 294,821 RSUs to certain officers of the Company under the 2006 Plan, which included 168,077 RSUs (at the target level of performance), or 57% , that are subject to time-based, market and performance-based vesting requirements (each a “2016 Performance-Based RSU” and collectively, the “2016 Performance-Based RSU Grant”) and 126,744 RSUs, or 43% , that are subject to time-based vesting requirements (each a “2016 Time-Based RSU” and collectively, the “2016 Time-Based RSU Grant”). On January 27, 2015 (the “2015 RSU Grant Date”), the Compensation Committee of the Company’s Board of Directors awarded 212,468 RSUs to certain officers of the Company under the 2006 Plan, which included 127,657 RSUs that are subject to time-based, market and performance-based vesting requirements (each a “2015 Performance-Based RSU” and collectively, the “2015 Performance-Based RSU Grant”) and 84,811 RSUs that are subject to time-based vesting requirements (each a “2015 Time-Based RSU” and collectively, the “2015 Time-Based RSU Grant”). 2016 and 2015 Performance-Based RSU Grants The 2016 Performance-Based RSUs and 2015 Performance-Based RSUs (collectively, the “Performance-Based RSUs”) are scheduled to cliff vest at the end of a three-year service period subject to the compensation committee's determination that the Company has achieved the pre-defined FFO per share goals (the “performance conditions”) and upon the average annual relative total stockholder return versus a comparator group of Companies that consist of Companies in the SNL US REIT Office Index (the “market conditions”) for the three-year periods detailed in the table below. The number of Performance-Based RSUs ultimately earned, and therefore the compensation costs for these awards, can fluctuate from the original number of RSUs granted based upon the levels of achievement for both the FFO per share and relative total stockholder return metrics. During each of the 2016 and 2015 performance periods, the estimate of the number of RSUs earned was evaluated quarterly based on our forecasted level of achievement of the FFO per share hurdle. As of December 31, 2016 , the FFO per share hurdle performance conditions were achieved at approximately 144% of target for the 2016 Performance-Based RSUs. As of December 31, 2015 , the FFO per share hurdle performance conditions were achieved at 150% of target for the 2015 Performance-Based RSUs. As a result, the number of RSUs earned as of that date based on the FFO per share performance, excluding the impact of forfeitures, was as follows: 2016 Performance-Based RSU Grant 2015 Performance-Based RSU Grant Service vesting period January 28, 2016 - January 5, 2019 January 27, 2015 - January 5, 2018 Target RSUs granted 168,077 127,657 Estimated RSUs earned based on FFO per share performance condition 241,438 185,510 Date of fair valuation January 28, 2016 January 27, 2015 Each Performance-Based RSU represents the right to receive one share of our common stock in the future, subject to, and as modified by, the Company's level of achievement of the market condition. The fair value of the 2016 Performance-Based RSU Grant was $9.6 million at January 28, 2016 and the fair value of the 2015 Performance-Based RSU Grant was $10.1 million at January 27, 2015. The fair value for each grant was calculated using a Monte Carlo simulation pricing model based on the assumptions in the table below. The determination of the fair value of the Performance-Based RSU Grants take into consideration the likelihood of achievement of both the performance condition and the market condition discussed above. For the year ended December 31, 2016 , we recorded compensation expense for the 2016 Performance-Based RSU Grant based upon the $57.08 fair value per share at January 28, 2016 multiplied by the 241,438 RSUs estimated to be earned at December 31, 2016 . For the years ended December 31, 2016 and 2015 , we recorded compensation expense for the 2015 Performance-Based RSU Grant based upon the $78.55 fair value per share at January 27, 2015 multiplied by the 185,510 RSUs, which is net of forfeitures, estimated to be earned at December 31, 2015 . Compensation expense for the Performance-Based RSUs is recorded on a straight-line basis over the respective three-year periods. The following table summarizes the assumptions utilized in the Monte Carlo simulation pricing models: 2016 Award Fair Value Assumptions 2015 Award Fair Value Assumptions Valuation date January 28, 2016 January 27, 2015 Fair value per share on valuation date $57.08 $78.55 Expected share price volatility 26.00% 20.00% Risk-free interest rate 1.13% 0.92% Remaining expected life 2.9 years 2.9 years The computation of expected volatility was based on a blend of the historical volatility of our shares of common stock over approximately five years, as this is expected to be most consistent with future volatility and equates to a time period twice as long as the approximate two and a half year remaining performance period of the RSUs and implied volatility data based on the observed pricing of six month publicly-traded options on shares of our common stock. The risk-free interest rate was based on the yield curve on zero-coupon U.S. Treasury STRIP securities in effect at January 28, 2016 and January 27, 2015. 2016 and 2015 Time-Based RSU Grants The 2016 and 2015 Time-Based RSUs (collectively, the “Time-Based RSUs”) are scheduled to vest in equal installments over the periods listed below. Compensation expense for the Time-Based RSUs will be recognized on a straight-line basis from the grant date through the continued service vesting periods. Each Time-Based RSUs represents the right to receive one share of our common stock in the future, subject to continued employment through the applicable vesting date. The total fair value of the Time-Based RSUs is based on the Company's closing share price on the NYSE on the respective fair valuation dates as detailed in the table below: 2016 Time-Based RSU Grant 2015 Time-Based RSU Grant Service vesting period January 28, 2016 - January 5, 2019 January 27, 2015 - January 5, 2018 Fair value on valuation date (in millions) $ 7.1 $ 6.4 Fair value per share $ 56.23 $ 75.34 Date of fair valuation January 28, 2016 January 27, 2015 Summary of Market-Measure Based RSUs A summary of our market-measure based RSU activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested RSUs Vested RSUs Total RSUs Amount Weighted-Average (1) Outstanding at January 1, 2016 425,452 $ 67.68 — 425,452 Granted 258,393 57.36 — 258,393 Vested (36,914 ) 43.53 36,914 — Settled (2) (36,914 ) (36,914 ) Issuance of dividend equivalents (3) 12,120 65.50 — 12,120 Outstanding as of December 31, 2016 (4) 659,051 $ 64.95 — 659,051 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014. (2) Represents vested RSUs that were settled in shares of the Company’s common stock. Total shares settled include 19,264 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the RSUs settled. We accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy tax obligations. (3) Represents the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement. (4) Outstanding RSUs as of December 31, 2016 represent the achievement of the maximum performance conditions and assumed target levels for the market conditions. The number of restricted stock units ultimately earned is subject to change based upon actual performance over the three-year vesting period. Dividend equivalents earned will vest along with the underlying award and are also subject to changes based on the number of RSUs ultimately earned for each underlying award. A summary of our market-measure based RSU activity for years ended December 31, 2016 , 2015 and 2014 is presented below: RSUs Granted RSUs Vested Years ended December 31, Non-Vested RSUs Granted Weighted-Average Fair Value Per Share (1) Vested RSUs Total Vest-Date Fair Value (in thousands) 2016 258,393 $ 57.36 (36,914 ) $ 2,788 2015 191,483 79.25 — — 2014 183,365 64.86 (16,338 ) 1,092 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014. Summary of Time-Based RSUs A summary of our time-based RSU activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested RSUs Vested RSUs Total RSUs Amount Weighted Average Fair Value (1) Outstanding at January 1, 2016 318,449 $ 58.91 951,360 1,269,809 Granted 173,747 58.29 — 173,747 Vested (130,784 ) 57.91 130,784 — Settled (2) (72,148 ) (72,148 ) Issuance of dividend equivalents (3) 5,027 65.78 23,243 28,270 Canceled (4) (4,489 ) (4,489 ) Outstanding as of December 31, 2016 366,439 $ 59.07 1,028,750 1,395,189 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014. (2) Represents vested RSUs that were settled in shares of the Company’s common stock. Total shares settled include 23,087 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the RSUs settled. We accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy tax obligations. (3) Represents the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement. (4) For shares vested but not yet settled, we accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy minimum statutory tax-withholding requirements related to either the settlement or vesting of RSUs in accordance with the terms of the 2006 Plan. A summary of our time-based RSU activity for the years ended December 31, 2016 , 2015 and 2014 is presented below: RSUs Granted RSUs Vested Year ended December 31, Non-Vested RSUs Issued Weighted-Average Grant Date Fair Value Per Share Vested RSUs Total Vest-Date Fair Value (1) (in thousands) 2016 173,747 $ 58.29 (130,784 ) $ 8,438 2015 98,802 74.49 (107,541 ) 7,528 2014 155,016 59.89 (116,447 ) 6,675 _______________ (1) Total fair value of RSUs vested was calculated based on the quoted closing share price of the Company’s common stock on the NYSE on the day of vesting. Excludes the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement. Summary of Nonvested Restricted Stock A summary of our nonvested restricted stock activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested Weighted-Average Outstanding at January 1, 2016 60,797 $ 47.32 Vested (1) (24,262 ) 46.39 Outstanding as of December 31, 2016 36,535 $ 47.93 _______________ (1) The total shares vested includes 12,661 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the restricted shares that have vested. We accept the return of shares at the current quoted closing share price of the Company’s common stock to satisfy tax withholding obligations. A summary of our nonvested and vested restricted stock activity for years ended December 31, 2016 , 2015 and 2014 is presented below: Shares Granted Shares Vested Years ended December 31, Nonvested Shares Issued Weighted-Average Grant Date Fair Value Per Share Vested Shares Total Fair Value at Vest Date (1) (in thousands) 2016 — $ — (24,262 ) $ 1,527 2015 — — (24,264 ) 1,725 2014 213 51.35 (25,899 ) 1,323 _______________ (1) Total fair value of shares vested was calculated based on the quoted closing share price of the Company’s common stock on the NYSE on the date of vesting. Summary of Stock Options On February 22, 2012, the Compensation Committee of the Company granted non-qualified stock options to certain key members of our senior management team, including our Executive Officers, to purchase an aggregate 1,550,000 shares of the Company’s common stock (the “February 2012” Grant) at an exercise price per share equal to $42.61 , the closing price of the Company’s common stock on the grant date. The options will vest ratably in annual installments over a five year period, subject to continued employment through the applicable vesting date. The term of each option is ten years from the date of the grant. Dividends will not be paid on vested or unvested options. The options were granted pursuant to the 2006 Plan. The fair value of each stock option granted is estimated on the date of grant using the Black-Scholes option pricing model based on the following assumptions for the February 2012 Grant. February 2012 Option Grant Fair value of options granted per share $9.20 Expected stock price volatility 33.00% Risk-free interest rate 1.35% Dividend yield 3.80% Expected life of option 6.5 years The computation of expected volatility is based on a blend of the historical volatility of our shares of common stock over a time period longer than the expected life of the option and implied volatility data based on the observed pricing of six-month publicly traded options on our shares of common stock. The risk-free interest rate is based on the yield curve on zero-coupon U.S. Treasury STRIP securities in effect at the grant date. The expected dividend yield is estimated by examining the average of the historical dividend yield levels over the expected life of the option and the current dividend yield as of the grant date. The expected life of the options is calculated as the average of the vesting term and the contractual term. During the year ended December 31, 2016 , 267,000 stock options vested with a total fair value of $2.5 million . During the year ended December 31, 2015 , 298,000 stock options vested with a total fair value of $2.7 million . During the year ended December 31, 2014 , 304,000 stock options vested with a total fair value of $2.8 million . A summary of our stock option activity related to the February 2012 grant from January 1, 2016 through December 31, 2016 is presented below: Number of Options Exercise Price Intrinsic Value (in millions) (1) Outstanding at December 31, 2015 610,000 $ 42.61 $ 12.6 Exercised (286,500 ) 42.61 8.4 Forfeited (9,000 ) 42.61 0.1 Outstanding at December 31, 2016 (2) 314,500 $ 42.61 $ 9.6 Options exercisable at December 31, 2016 (3) 50,500 $ 42.61 $ 1.5 _______________ (1) The intrinsic value of a stock option is the amount by which the fair value of the underlying stock exceeds the exercise price of an option. The fair value of the underlying stock was determined by using the closing share price on the NYSE on the date of exercise, forfeiture or respective period end. (2) As of December 31, 2016 , the average remaining life of stock options outstanding was 5.1 years (3) As of December 31, 2016 , the average remaining life of stock options exercisable was approximately 5.1 years. In accordance with the provisions of the 2006 Plan, we allow shares of our common stock to be withheld to satisfy the payment of exercise price and/or minimum statutory tax withholding obligations due upon the exercise of stock options. The value of the shares withheld is calculated based on the closing market price of our common stock on the NYSE on the exercise date. During the year ended December 31, 2016 , 25,680 shares were withheld on stock option exercises with an aggregate value of $1.8 million . During the year ended December 31, 2015, 62,072 shares were withheld on stock option exercises with an aggregate value of $3.9 million . During the year ended December 31, 2014, 23,664 shares were withheld on stock option exercises with an aggregate value of $1.5 million . Share-Based Compensation Cost Recorded During the Period The total compensation cost for all share-based compensation programs was $26.6 million , $18.9 million and $14.5 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. Of the total share-based compensation costs, $5.6 million , $3.3 million and $2.3 million was capitalized as part of real estate assets and deferred leasing costs for the years ended December 31, 2016 , 2015 and 2014 , respectively. As of December 31, 2016 , there was approximately $29.6 million of total unrecognized compensation cost related to nonvested incentive awards granted under share-based compensation arrangements that is expected to be recognized over a weighted-average period of 1.8 years. The remaining compensation cost related to these nonvested incentive awards had been recognized in periods prior to December 31, 2016 . The $29.6 million of unrecognized compensation costs does not reflect the future compensation cost related to share-based awards that were granted subsequent to December 31, 2016 .

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Benefit Plans	Employee Benefit Plans 401(k) Plan We have a retirement savings plan designed to qualify under Section 401(k) of the Code (the “401(k) Plan”). Our employees are eligible to participate in the 401(k) Plan on the first day of the month after three months of service. The 401(k) Plan allows eligible employees (“401(k) Participants”) to defer up to 60% of their eligible compensation on a pre-tax basis, subject to certain maximum amounts allowed by the Code. The 401(k) Plan provides for a matching contribution by the Company in an amount equal to 50 cents of each one dollar of participant contributions up to a maximum of 10% of the 401(k) Participant’s annual salary. 401(k) Participants vest immediately in the amounts contributed by us. For each of the years ended December 31, 2016 , 2015 , and 2014 , we contributed $1.2 million , $1.1 million and $1.0 million , respectively, to the 401(k) Plan. Deferred Compensation Plan In 2007, we adopted the Deferred Compensation Plan, under which directors and certain management employees may defer receipt of their compensation, including up to 70% of their salaries and up to 100% of their director fees and bonuses, as applicable. In addition, employee participants will receive mandatory Company contributions to their Deferred Compensation Plan accounts equal to 10% of their gross monthly salaries, without regard to whether such employees elect to defer salary or bonus compensation under the Deferred Compensation Plan. Our board of directors may, but has no obligation to, approve additional discretionary contributions by the Company to Participant accounts. We hold the Deferred Compensation Plan assets in a limited rabbi trust, which is subject to the claims of our creditors in the event of bankruptcy or insolvency. See Note 19 “Fair Value Measurements and Disclosures” for further discussion of our Deferred Compensation Plan assets as of December 31, 2016 and 2015 . Our liability of $14.7 million and $12.8 million under the Deferred Compensation Plan was fully funded as of December 31, 2016 and 2015 , respectively.

Future Minimum Rent

Future Minimum Rent	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Future Minimum Rent	Future Minimum Rent We have operating leases with tenants that expire at various dates through 2035 and are either subject to scheduled fixed increases or adjustments in rent based on the Consumer Price Index. Generally, the leases grant tenants renewal options. Leases also provide for additional rents based on certain operating expenses. Future contractual minimum rent under operating leases as of December 31, 2016 for future periods is summarized as follows: Year Ending (in thousands) 2017 $ 538,269 2018 537,891 2019 493,998 2020 424,791 2021 370,941 Thereafter 1,901,303 Total (1) $ 4,267,193 ______________ (1) Excludes residential leases and leases with a term of one year or less.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies General As of December 31, 2016 , we had commitments of approximately $538.6 million , excluding our ground lease commitments, for contracts and executed leases directly related to our operating and development properties. Ground Leases The following table summarizes our properties that are held subject to long-term noncancellable ground lease obligations and the respective contractual expiration dates: Property Contractual Expiration Date (1) 601 108th Ave NE, Bellevue, WA November 2093 701, 801 and 837 N. 34th Street, Seattle, WA (2) December 2041 1701 Page Mill Road and 3150 Porter Drive, Palo Alto, CA December 2067 Kilroy Airport Center Phases I, II, and III, Long Beach, CA July 2084 ____________________ (1) Reflects the contractual expiration date prior to the impact of any extension or purchase options held by the Company. (2) The Company has three 10 year and one 45 year extension options for this ground lease, which if exercised would extend the expiration date to December 2116. The minimum commitment under our ground leases as of December 31, 2016 for five years and thereafter is as follows: Year Ending (in thousands) 2017 $ 4,934 2018 4,934 2019 4,934 2020 4,934 2021 4,934 Thereafter 231,402 Total (1)(2)(3)(4)(5) $ 256,072 ________________________ (1) Excludes contingent future rent payments based on gross income or adjusted gross income and reflects the minimum ground lease obligations before the impact of ground lease extension options. (2) One of our ground lease obligations is subject to a fair market value adjustment every five years ; however, the lease includes ground rent subprotection and infrastructure rent credits which currently limit our annual rental obligations to $1.0 million . The contractual obligations for that ground lease included above assumes the lesser of $1.0 million or annual lease rental obligation in effect as of December 31, 2016 . (3) One of our ground lease obligations includes a component which is based on the percentage of gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every five years based on 50% of the average annual percentage rent for the previous five years. (4) One of our ground lease obligations is subject to a fair market value adjustment every five years based on a combination of CPI adjustments and third-party appraisals limited to maximum increases annually. The contractual obligations included above assume the annual lease rental obligation in effect as of December 31, 2016 . (5) One of our ground lease obligations includes a component which is based on the percentage of adjusted gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every 10 years by an amount equal to 60% of the average annual percentage rent for the previous three years. Environmental Matters We follow the policy of monitoring all of our properties, both acquisition and existing stabilized portfolio properties, for the presence of hazardous or toxic substances. While there can be no assurance that a material environmental liability does not exist, we are not currently aware of any environmental liability with respect to our stabilized portfolio properties that would have a material adverse effect on our financial condition, results of operations and cash flow, or that we believe would require additional disclosure or the recording of a loss contingency. As of December 31, 2016 and 2015 , we had accrued environmental remediation liabilities of approximately $25.1 million and $20.9 million , respectively, recorded on our consolidated balance sheets in connection with certain development projects and recent development acquisitions. The accrued environmental remediation liabilities represent the costs we estimate we will incur when we commence development at various development acquisition sites. These estimates, which we developed with the assistance of third party experts, consist primarily of the removal of contaminated soil and other related costs since we are required to dispose of any existing contaminated soil when we develop new office properties as these sites. We record estimated environmental remediation obligations for acquisitions at the acquisition date when we are aware of such costs and when such costs are probably and reasonably estimable. Costs incurred in connection with the development related environmental remediation liabilities are recorded as an increase to the cost of the development project. These accruals are adjusted as an increase or decrease to the development project costs and as an increase or decrease to the accrued environmental remediation liability if we obtain further information or circumstances change. The environmental remediation obligations recorded at December 31, 2016 and 2015 were not discounted to their present value since we expect to complete the remediation activities in the next one to five years in connection with development activities at the various sites. It is possible that we could incur additional environmental remediation costs in connection with these recent development acquisitions. However, given we are in the early stages of development on certain of these projects, potential additional environmental costs are not reasonably estimable at this time. Other than the accrued environmental liabilities recorded in connection with certain of our development projects, we are not aware of any unasserted claims and assessments with respect to an environmental liability that we believe would require additional disclosure or the recording of an additional loss contingency. Litigation We and our properties are subject to litigation arising in the ordinary course of business. To our knowledge, neither we nor any of our properties are presently subject to any litigation or threat of litigation which, if determined unfavorably to us, would have a material adverse effect on our cash flow, financial condition, or results of operations. Insurance We maintain commercial general liability, auto liability, employers’ liability, umbrella/excess liability, special form property, difference in conditions including earthquake and flood, environmental, rental loss, and terrorism insurance covering all of our properties. Management believes the policy specifications and insured limits are reasonable given the relative risk of loss, the cost of the coverage, and industry practice. We do not carry insurance for generally uninsurable losses such as loss from governmental action, nuclear hazard, and war and military action. Policies are subject to various terms, conditions, and exclusions and some policies may involve large deductibles or co-payments. Property Damage Settlement During the year ended December 31, 2016 , we settled an outstanding property damage matter and received cash proceeds totaling $5.0 million , which is included in other property income on our consolidated statements of operations.

Fair Value Measurements and Dis

Fair Value Measurements and Disclosures	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements and Disclosures	Fair Value Measurements and Disclosures Assets and Liabilities Reported at Fair Value The only assets we record at fair value on our consolidated financial statements are the marketable securities related to our Deferred Compensation Plan (see Note 16 “Employee Benefit Plans” for additional information). The following table sets forth the fair value of our marketable securities as of December 31, 2016 and 2015 : Fair Value (Level 1) (1) 2016 2015 Description (in thousands) Marketable securities (2) $ 14,773 $ 12,882 _______________ (1) Based on quoted prices in active markets for identical securities. (2) The marketable securities are held in a limited rabbi trust . We report the change in the fair value of the marketable securities at the end of each accounting period in interest income and other net investment gains (losses) in the consolidated statements of operations. We also adjust the related Deferred Compensation Plan liability to fair value at the end of each accounting period based on the performance of the benchmark funds selected by each participant, which results in a corresponding increase or decrease to compensation cost for the period. The following table sets forth the net gain (loss) on marketable securities recorded during the years ended December 31, 2016 , 2015 and 2014 : December 31, 2016 2015 2014 Description (in thousands) Net gain (loss) on marketable securities $ 1,130 $ (269 ) $ 397 Financial Instruments Disclosed at Fair Value The following table sets forth the carrying value and the fair value of our other financial instruments as of December 31, 2016 and 2015 : December 31, 2016 2015 Carrying Value Fair Value (1) Carrying Value Fair Value (1) (in thousands) Liabilities Secured debt, net $ 472,772 $ 469,234 $ 380,835 $ 391,611 Unsecured debt, net 1,847,351 1,900,487 1,844,634 1,898,863 _______________ (1) Fair value calculated using Level II inputs, which are based on model-derived valuations in which significant inputs and significant value drivers are observable in active markets.

Other Significant Events

Other Significant Events	12 Months Ended
	Dec. 31, 2016
Other Income and Expenses [Abstract]
Other Significant Events	Other Significant Transactions In January 2014, a tenant at one of our San Diego, California operating properties exercised an early lease termination clause as permitted under the terms of their lease. As a result, the lease which encompasses approximately 79,000 rentable square feet and was scheduled to expire in February 2020, terminated during the year ended December 31, 2014. The total lease termination fee of $5.7 million was recorded as other property income on a straight line basis through the early lease termination date. The Company received the cash payment of the lease termination fee of $5.7 million in September 2014. During the year ended December 31, 2014 , the Company also recognized approximately $1.3 million as a reduction to rental income due to the accelerated amortization of the deferred rent receivable and above market lease for this tenant.

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Dispositions and Real Estate Assets Held for Sale Operating Property Dispositions The following table summarizes the operating properties sold during the years ended December 31, 2016 , 2015 and 2014 : Location Month of Disposition Number of Buildings Rentable Square Feet (unaudited) Sales Price (in millions) (1) 2016 Dispositions Torrey Santa Fe Properties (2) January 4 465,812 $ 262.3 4930, 4939 & 4955 Directors Place, San Diego, CA (3) July 2 136,908 49.0 Total 2016 Dispositions 6 602,720 $ 311.3 2015 Dispositions 15050 NE 36th Street, Redmond, WA April 1 122,103 $ 51.2 San Diego Properties - Tranches 1 and 2 (4) April/July 9 924,291 258.0 Total 2015 Dispositions 10 1,046,394 $ 309.2 2014 Dispositions (5) San Diego Properties, San Diego, CA (6) January 12 1,049,035 $ 294.7 9785 & 9791 Towne Centre Drive, San Diego, CA June 2 126,000 29.5 111 Pacifica, Irvine, CA September 1 67,496 15.1 4040 Civic Center Drive, San Rafael, CA October 1 130,237 34.9 999 Town & Country Road, Orange, CA December 1 98,551 25.3 Total 2014 Dispositions 17 1,471,319 $ 399.5 __________________ (1) Represents gross sales price before the impact of broker commissions and closing costs. (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe and 7555 Torrey Santa Fe. These properties were classified as held for sale at December 31, 2015 . (3) Includes two operating properties totaling 136,908 rentable square feet and a 7.0 acre undeveloped land parcel. (4) The San Diego Properties - Tranche 1 includes the following properties: 10770 Wateridge Circle, 6200 Greenwich Drive and 6220 Greenwich Drive. The San Diego Properties - Tranche 2 includes the following properties: 6260 Sequence Drive, 6290, Sequence Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive and 4921 Directors Place. (5) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, results of operations for properties disposed of subsequent of January 1, 2015 are presented in continuing operations because they did not represent strategic shifts. Properties disposed of prior to January 1, 2015 are presented in discontinued operations. (6) The San Diego Properties included the following properties: 10020 Pacific Mesa Boulevard, 6055 Lusk Avenue, 5010 and 5005 Wateridge Vista Drive, 15435 and 15445 Innovation Drive, and 15051, 15073, 15231, 15253, 15333 and 15378 Avenue of Science. These properties were held for sale as of December 31, 2013. The operations of the six properties sold during the year ended December 31, 2016 and ten properties sold during the year ended December 31, 2015 are presented in continuing operations for the years ended December 31, 2016 and December 31, 2015 , respectively. For the year ended December 31, 2014 , discontinued operations includes the income and gains on all of the properties sold in 2014 (see Note 2 “Basis of Presentation and Significant Accounting Policies” and Note 21 “Discontinued Operations” for additional information). The total gains on sales of the six properties sold during the year ended December 31, 2016 was $164.3 million . The total gains on sales of the ten properties sold during the year ended December 31, 2015 was $110.0 million . The total gains on sales of the 17 properties sold during the year ended December 31, 2014 was $121.9 million . Operating Properties Held for Sale As of December 31, 2016 and 2015 , the properties listed below were classified as held for sale. Properties Submarket Property Type Number of Buildings Rentable Square Feet (unaudited) 2016 Held for Sale 5717 Pacific Center Drive (1) Sorrento Mesa Office 1 67,995 2015 Held for Sale Torrey Santa Fe Properties (2)(3) Del Mar Office 4 465,812 __________________ (1) In January 2017, the Company completed the sale of this property for a total sales price of $12.1 million . (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe, and 7555 Torrey Santa Fe. (3) In January 2016, the Company completed the sale of these properties for a total sales price of $262.3 million . The major classes of assets and liabilities of the properties held for sale as of December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Real estate assets and other assets held for sale (in thousands) Land and improvements $ 2,693 $ 10,534 Buildings and improvements 10,500 144,716 Undeveloped land and construction in progress — 4,824 Total real estate held for sale 13,193 160,074 Accumulated depreciation and amortization (3,900 ) (46,191 ) Total real estate held for sale, net 9,293 113,883 Deferred rent receivables, net — 2,500 Deferred leasing costs and acquisition-related intangible assets, net — 1,115 Prepaid expenses and other assets, net 124 168 Real estate and other assets held for sale, net $ 9,417 $ 117,666 Liabilities and deferred revenue of real estate assets held for sale Secured debt $ — $ 561 Accounts payable, accrued expenses and other liabilities 56 2,497 Deferred revenue and acquisition-related intangible liabilities, net — 2,899 Rents received in advance and tenant security deposits — 1,586 Liabilities and deferred revenue of real estate assets held for sale $ 56 $ 7,543 Land Dispositions The following table summarizes the land dispositions completed during the years ended December 31, 2016 , 2015 and 2014 : Properties Submarket Month of Disposition Gross Site Acreage (unaudited) Sales Price (1) (in millions) 2016 Land Dispositions Carlsbad Oaks - Lot 7 (2) Carlsbad January 7.6 $ 4.5 Carlsbad Oaks - Lots 4 & 5 Carlsbad June 11.2 6.0 Carlsbad Oaks - Lot 8 Carlsbad June 13.2 8.9 Total 2016 Land Dispositions (3)(4) 32.0 $ 19.4 2015 Land Disposition 17150 Von Karman (4) Irvine January 8.5 $ 26.0 2014 Land Disposition 10850 Via Frontera (4) Rancho Bernardo April 21.0 $ 33.1 __________________ (1) Represents gross sales price before the impact of commissions and closing costs. (2) This land parcel was classified as held for sale as of December 31, 2015. (3) In connection with these land dispositions, $2.3 million of secured debt was assumed by the buyers. See Note 9 “Secured and Unsecured Debt of the Operating Partnership” for additional information. (4) The 2016 land dispositions resulted in a net loss on sales of $0.3 million and the 2015 and 2014 land dispositions resulted in gain on sales of $17.3 million and $3.5 million , respectively. Land Held for Sale We did not have any land classified as held for sale as of December 31, 2016 . As of December 31, 2015 , the following land parcel was classified as held for sale: Properties Submarket Gross Site Acreage (unaudited) Sales Price 2015 Held for Sale Carlsbad Oaks - Lot 7 (1) Carlsbad 7.6 $ 4.5 __________________ (1) During the year ended December 31, 2015, the Company recognized a loss relating to selling costs of approximately $0.2 million . Restricted Cash Related to Dispositions As of December 31, 2016 approximately $48.4 million of net proceeds related to the land and operating property dispositions during the year ended December 31, 2016 were temporarily being held at a qualified intermediary, at our direction, for the purpose of facilitating Section 1031 Exchanges. The cash proceeds were included in restricted cash on the consolidated balance sheet at December 31, 2016 . During January 2017, the Section 1031 Exchange was successfully completed and the cash proceeds were released from the qualified intermediary. We did not have any restricted cash related to dispositions or Section 1031 Exchanges as of December 31, 2015 . Discontinued Operations For the year ended December 31, 2014 , discontinued operations included the results of all properties sold in 2014, except for the operations deemed immaterial related to a June 2014 office property disposition. The following table summarizes the revenue and expense components that comprise income from discontinued operations for the year ended December 31, 2014 : 2014 (in thousands) Revenues: Rental income $ 7,206 Tenant reimbursements 278 Other property income 13 Total revenues 7,497 Expenses: Property expenses 2,171 Real estate taxes 692 Depreciation and amortization 2,061 Total expenses 4,924 Income from discontinued operations before net gain on dispositions of discontinued operations 2,573 Net gain on dispositions of discontinued operations 121,922 Total income from discontinued operations $ 124,495

Net Income Available to Common

Net Income Available to Common Stockholders Per Share of the Company	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Net Income Available to Common Stockholders Per Share of the Company	Net Income Available to Common Stockholders Per Share of the Company The following table reconciles the numerator and denominator in computing the Company’s basic and diluted per-share computations for net income available to common stockholders for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 303,798 $ 238,604 $ 59,313 Income from continuing operations attributable to noncontrolling interests (10,010 ) (4,523 ) (966 ) Preferred dividends and distributions (13,250 ) (13,250 ) (13,250 ) Allocation to participating securities (1) (3,839 ) (1,634 ) (1,699 ) Numerator for basic and diluted income from continuing operations available to common stockholders 276,699 219,197 43,398 Income from discontinued operations (2) — — 124,495 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — — (2,623 ) Numerator for basic and diluted net income available to common stockholders $ 276,699 $ 219,197 $ 165,270 Denominator: Basic weighted average vested shares outstanding 92,342,483 89,854,096 83,090,235 Effect of dilutive securities – contingently issuable shares and stock options 680,551 541,679 1,877,485 Diluted weighted average vested shares and common stock equivalents outstanding 93,023,034 90,395,775 84,967,720 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 3.00 $ 2.44 $ 0.52 Income from discontinued operations per share of common stock (2) — — 1.47 Net income available to common stockholders per share $ 3.00 $ 2.44 $ 1.99 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 2.97 $ 2.42 $ 0.51 Income from discontinued operations per share of common stock (2) — — 1.44 Net income available to common stockholders per share $ 2.97 $ 2.42 $ 1.95 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs. (2) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are no longer presented as discontinued operations. Share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are considered participating securities. The impact of potentially dilutive shares of common stock, including stock options, RSUs and other securities are considered in our diluted earnings per share calculation for the years ended December 31, 2016 , 2015 , and 2014 . Additionally, for the year ended December 31, 2014, contingently issuable shares included the impact of the 4.25% Exchangeable Notes prior to their maturity and settlement in November 2014. Certain market measure-based RSUs are not included in dilutive securities as of December 31, 2016 , 2015 , and 2014 as not all performance metrics had been met by the end of the applicable reporting periods. See Note 15 “Share-Based Compensation” for additional information regarding the stock options and other share-based compensation.

Net Income Available to Commo36

Net Income Available to Common Unitholders Per Unit of the Operating Partnership	12 Months Ended
	Dec. 31, 2016
Kilroy Realty, L.P. [Member]
Net Income Available To Common Unitholders [Line Items]
Net Income Available to Common Unitholders per Unit of the Operating Partnership	Net Income Available to Common Unitholders Per Unit of the Operating Partnership The following table reconciles the numerator and denominator in computing the Operating Partnership’s basic and diluted per-unit computations for net income available to common unitholders for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 303,798 $ 238,604 $ 59,313 Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries (3,735 ) (467 ) (247 ) Preferred distributions (13,250 ) (13,250 ) (13,250 ) Allocation to participating securities (1) (3,839 ) (1,634 ) (1,699 ) Numerator for basic and diluted income from continuing operations available to common unitholders 282,974 223,253 44,117 Income from discontinued operations (2) — — 124,495 (Income) loss from discontinued operations attributable to noncontrolling interests in consolidated subsidiaries (2) — — (13 ) Numerator for basic and diluted net income available to common unitholders $ 282,974 $ 223,253 $ 168,599 Denominator: Basic weighted average vested units outstanding 94,771,688 91,645,578 84,894,498 Effect of dilutive securities - contingently issuable shares and stock options 680,551 541,679 1,877,485 Diluted weighted average vested units and common unit equivalents outstanding 95,452,239 92,187,257 86,771,983 Basic earnings per unit: Income from continuing operations available to common unitholders per unit $ 2.99 $ 2.44 $ 0.52 Income from discontinued operations per common unit (2) — — 1.47 Net income available to common unitholders per unit $ 2.99 $ 2.44 $ 1.99 Diluted earnings per unit: Income from continuing operations available to common unitholders per unit $ 2.96 $ 2.42 $ 0.51 Income from discontinued operations per common unit (2) — — 1.43 Net income available to common unitholders per unit $ 2.96 $ 2.42 $ 1.94 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs. (2) The Operating Partnership adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are no longer presented as discontinued operations. Share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are considered participating securities. The impact of potentially dilutive common units, including stock options, RSUs and other securities are considered in our diluted earnings per share calculation for the years ended December 31, 2016 , 2015 , and 2014 . Additionally, for the year ended December 31, 2014, contingently issuable shares included the impact of the 4.25% Exchangeable Notes prior to their maturity and settlement in November 2014. Certain market measure-based RSUs are not included in dilutive securities as of December 31, 2016 and 2015 as not all performance metrics had been met by the end of the applicable reporting periods. See Note 15 “Share-Based Compensation” for additional information regarding the stock options and other share-based compensation.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information of the Company	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information of the Company	Supplemental Cash Flow Information of the Company Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common unitholders (Notes 13 and 29) $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 13 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units of the Operating Partnership in connection with an acquisition $ 48,033 $ — $ — Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ — Issuance of shares of common stock in connection with a development property $ — $ — $ 21,631 Exchange of common units of the Operating Partnership into shares of the Company’s common stock $ 8,893 $ 1,223 $ 28 Supplemental Cash Flow Information of the Operating Partnership: Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 14 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units in connection with a development property acquisition (Note 3) $ 48,033 $ — $ 21,631 Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ —

Supplemental Cash Flow Inform38

Supplemental Cash Flow Information of the Operating Partnership	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information of the Operating Partnership	Supplemental Cash Flow Information of the Company Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common unitholders (Notes 13 and 29) $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 13 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units of the Operating Partnership in connection with an acquisition $ 48,033 $ — $ — Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ — Issuance of shares of common stock in connection with a development property $ — $ — $ 21,631 Exchange of common units of the Operating Partnership into shares of the Company’s common stock $ 8,893 $ 1,223 $ 28 Supplemental Cash Flow Information of the Operating Partnership: Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 14 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units in connection with a development property acquisition (Note 3) $ 48,033 $ — $ 21,631 Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ —

Tax Treatment of Distributions

Tax Treatment of Distributions	12 Months Ended
	Dec. 31, 2016
Tax Treatment of Distributions [Abstract]
Tax Treatment of Distributions	Tax Treatment of Distributions The following table reconciles the dividends declared per share of common stock to the dividends paid per share of common stock during the years ended December 31, 2016 , 2015 and 2014 as follows: Year Ended December 31, Dividends 2016 2015 2014 Dividends declared per share of common stock $ 3.375 $ 1.400 $ 1.400 Less: Dividends declared in the current year and paid in the following year (1) (2.275 ) (0.350 ) (0.350 ) Add: Dividends declared in the prior year and paid in the current year 0.350 0.350 0.350 Dividends paid per share of common stock $ 1.450 $ 1.400 $ 1.400 _________________ (1) The fourth quarter 2016 dividend of $2.275 per share of common stock consists of a special cash dividend of $1.90 per share of common stock and a regular quarterly cash dividend of $0.375 per share of common stock. The $1.90 per share special distribution is treated as paid in two tax years for income tax purposes: $1.587 is treated as paid on December 31, 2016 and $0.313 is treated as paid on January 13, 2017. The $0.375 per share regular quarterly distribution is considered a 2017 dividend distribution for income tax purposes. The unaudited income tax treatment for the dividends to common stockholders reportable for the years ended December 31, 2016 , 2015 and 2014 as identified in the table above was as follows: Year Ended December 31, Shares of Common Stock 2016 2015 2014 Ordinary income $ 1.500 49.40 % $ 0.992 70.86 % $ 0.998 71.29 % Qualified dividend 0.002 0.06 0.002 0.13 0.002 0.14 Return of capital — — — — 0.398 28.43 Capital gains (1) 1.212 39.89 0.051 3.65 0.002 0.14 Unrecaptured section 1250 gains 0.323 10.65 0.355 25.36 — — $ 3.037 100.00 % $ 1.400 100.00 % $ 1.400 100.00 % _________________ (1) Capital gains are comprised entirely of 20% rate gains. The 6.875% Series G Cumulative Redeemable Preferred Stock was issued in March 2012. The unaudited income tax treatment for the dividends to Series G preferred stockholders reportable for the years ended December 31, 2016 , 2015 , and 2014 was as follows: Year Ended December 31, Preferred Shares 2016 2015 2014 Ordinary income $ 0.848 49.31 % $ 1.218 70.86 % $ 1.711 99.54 % Qualified dividend 0.001 0.06 0.002 0.13 0.003 0.17 Capital gains (1) 0.687 39.97 0.063 3.65 0.005 0.29 Unrecaptured section 1250 gains 0.183 10.66 0.436 25.36 — — $ 1.719 100.00 % $ 1.719 100.00 % $ 1.719 100.00 % __________________ (1) Capital gains are comprised entirely of 20% rate gains. The 6.375% Series H Cumulative Redeemable Preferred Stock was issued in August 2012. The unaudited income tax treatment for the dividends to Series H preferred stockholders reportable for the years ended December 31, 2016 , 2015 , and 2014 was as follows: Year Ended December 31, Preferred Shares 2016 2015 2014 Ordinary income $ 0.786 49.31 % $ 1.129 70.86 % $ 1.587 99.56 % Qualified dividend 0.001 0.06 0.002 0.13 0.003 0.19 Capital gains (1) 0.637 39.97 0.059 3.65 0.004 0.25 Unrecaptured section 1250 gains 0.17 10.66 0.404 25.36 — — $ 1.594 100.00 % $ 1.594 100.00 % $ 1.594 100.00 % __________________ (1) Capital gains are comprised entirely of 20% rate gains.

Quarterly Financial Information

Quarterly Financial Information of the Company (Unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information of the Company (Unaudited)	Quarterly Financial Information of the Company (Unaudited) Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to Kilroy Realty Corporation 174,308 32,847 53,895 32,738 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 170,995 29,535 50,582 29,426 Net income available to common stockholders per share – basic 1.85 0.32 0.54 0.29 Net income available to common stockholders per share – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to Kilroy Realty Corporation 43,187 57,500 104,759 28,635 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 39,874 54,188 101,446 25,323 Net income available to common stockholders per share – basic 0.45 0.61 1.10 0.27 Net income available to common stockholders per share – diluted 0.45 0.61 1.09 0.27 ____________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the Company's repurchase of common stock and its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and its at-the-market stock offering programs that occurred during the year.

Quarterly Financial Informati41

Quarterly Financial Information of the Operating Partnership (Unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information of the Operating Partnership (Unaudited)	Quarterly Financial Information of the Company (Unaudited) Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to Kilroy Realty Corporation 174,308 32,847 53,895 32,738 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 170,995 29,535 50,582 29,426 Net income available to common stockholders per share – basic 1.85 0.32 0.54 0.29 Net income available to common stockholders per share – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to Kilroy Realty Corporation 43,187 57,500 104,759 28,635 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 39,874 54,188 101,446 25,323 Net income available to common stockholders per share – basic 0.45 0.61 1.10 0.27 Net income available to common stockholders per share – diluted 0.45 0.61 1.09 0.27 ____________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the Company's repurchase of common stock and its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and its at-the-market stock offering programs that occurred during the year.
Kilroy Realty, L.P. [Member]
Quarterly Financial Information of the Operating Partnership (Unaudited)	Quarterly Financial Information of the Operating Partnership (Unaudited) Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per unit amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to the Operating Partnership 177,833 33,590 55,254 33,386 Preferred distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common unitholders 174,520 30,278 51,941 30,074 Net income available to common unitholders per unit – basic 1.85 0.31 0.54 0.29 Net income available to common unitholders per unit – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per unit amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to the Operating Partnership 43,927 58,518 106,640 29,052 Preferred distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common unitholders 40,614 55,206 103,327 25,740 Net income available to common unitholders per unit – basic 0.45 0.61 1.10 0.27 Net income available to common unitholders per unit – diluted 0.45 0.61 1.09 0.27 ___________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the issuance of common units in connection with an acquisition, the Company’s repurchase of common stock and the its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and the Company’s at-the-market stock offering programs that occurred during the year.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On December 13, 2016, the Company declared a special cash dividend of $1.90 per share of common stock to stockholders of record on December 30, 2016 . This special cash dividend is in addition to the regular quarterly dividend. On January 13, 2017 , $184.3 million of special dividends and $36.4 million of regular dividends were paid out to common stockholders, common unitholders and RSU holders of record on December 30, 2016. On January 10, 2017, pursuant to the Company’s effective shelf registration statement and prospectus and related prospectus supplement filed with the Securities and Exchange Commission, the Company completed a public offering and issued 4,427,500 shares of its common stock at a price of $72.75 per share, before underwriting discounts and commissions. The Company received approximately $308.8 million of total proceeds, which are net of underwriting discounts and commissions and estimated offering expenses. The Company intends to use the net proceeds from the offering for general corporate purposes. On January 13, 2017, the Company completed the sale of the operating property located at 5717 Pacific Center Boulevard in San Diego, California that was held for sale at December 31, 2016 for a gross sales price of $12.1 million . In February 2017, the Executive Compensation Committee granted 41,119 RSUs to key employees under the 2006 Plan. The compensation cost related to the RSUs is expected to be recognized over a period of three years.

Schedule II Valuation and Quali

Schedule II Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2016
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	Balance at Beginning of Period Charged to Costs and Expenses Recoveries (Deductions) Balance at End of Period (1) Allowance for Uncollectible Tenant Receivables for the year ended December 31, 2016 – Allowance for uncollectible tenant receivables $ 2,080 $ — $ (368 ) $ 1,712 2015 – Allowance for uncollectible tenant receivables 1,999 303 (222 ) 2,080 2014 – Allowance for uncollectible tenant receivables 2,134 58 (193 ) 1,999 Allowance for Deferred Rent Receivables for the year ended December 31, 2016 – Allowance for deferred rent $ 1,882 $ — $ (358 ) $ 1,524 2015 – Allowance for deferred rent 1,989 242 (349 ) 1,882 2014 – Allowance for deferred rent 2,075 — (86 ) 1,989

Schedule III - Real Estate and

Schedule III - Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2016
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III - Real Estate and Accumulated Depreciation	The following table reconciles the historical cost of total real estate held for investment from January 1, 2014 to December 31, 2016 : Year Ended December 31, 2016 2015 2014 (in thousands) Total real estate held for investment, beginning of year $ 6,328,146 $ 6,057,932 $ 5,264,947 Additions during period: Acquisitions 460,957 139,123 340,296 Improvements, etc. 386,836 536,411 588,166 Total additions during period 847,793 675,534 928,462 Deductions during period: Cost of real estate sold (68,200 ) (231,984 ) (113,416 ) Properties held for sale (13,193 ) (160,074 ) (14,700 ) Other (33,792 ) (13,262 ) (7,361 ) Total deductions during period (115,185 ) (405,320 ) (135,477 ) Total real estate held for investment, end of year $ 7,060,754 $ 6,328,146 $ 6,057,932 The following table reconciles the accumulated depreciation from January 1, 2014 to December 31, 2016 : Year Ended December 31, 2016 2015 2014 (in thousands) Accumulated depreciation, beginning of year $ 994,241 $ 947,664 $ 818,957 Additions during period: Depreciation of real estate 171,983 159,524 153,841 Total additions during period 171,983 159,524 153,841 Deductions during period: Write-offs due to sale (22,471 ) (66,603 ) (18,111 ) Properties held for sale (3,900 ) (46,191 ) (7,007 ) Other — (153 ) (16 ) Total deductions during period (26,371 ) (112,947 ) (25,134 ) Accumulated depreciation, end of year $ 1,139,853 $ 994,241 $ 947,664

Basis of Presentation and Sig45

Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Basis of presentation and significant accounting policies [Line Items]
Basis of Presentation	The consolidated financial statements of the Company include the consolidated financial position and results of operations of the Company, the Operating Partnership, the Finance Partnership, KSLLC, 303 Second LLC, 100 First LLC, Redwood LLC and all of our wholly-owned and controlled subsidiaries. The consolidated financial statements of the Operating Partnership include the consolidated financial position and results of operations of the Operating Partnership, the Finance Partnership, KSLLC, 303 Second LLC, 100 First LLC, Redwood LLC and all wholly-owned and controlled subsidiaries of the Operating Partnership. All intercompany balances and transactions have been eliminated in the consolidated financial statements. Effective January 1, 2016, the Company adopted Financial Accounting Standards Board ("FASB") Accounting Standards Update (“ASU”) No. 2015-03 and No. 2015-15, which requires that debt issuance costs related to a recognized debt liability be presented on the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. However, for line-of-credit arrangements, entities may defer and present debt issuance costs as an asset and amortize the costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. As a result of our adoption of the guidance, $1.1 million of deferred financing costs as of December 31, 2015 were reclassified to reduce secured debt, net and $12.0 million of deferred financing costs as of December 31, 2015 were reclassified to reduce unsecured debt, net in the December 31, 2015 balances on our consolidated balance sheets. In addition, $4.6 million of deferred financing costs relating to our unsecured line of credit as of December 31, 2015 were reclassified to prepaid expenses and other assets, net in the December 31, 2015 balances on our consolidated balance sheets. The guidance did not have a material impact on our consolidated financial statements.
Partially Owned Entities and Variable Interest Entities	Effective January 1, 2016, the Company adopted FASB ASU No. 2015-02 (“ASU 2015-02”), which amended certain guidance with respect to the evaluation of Variable Interest Entities (“VIEs”) and when a reporting entity is required to consolidate certain legal entities. Specifically, the amendments: (i) modify the evaluation of whether limited partnerships and similar legal entities are VIEs or voting interest entities, (ii) eliminate the presumption that a general partner should consolidate a limited partnership, (iii) affect the consolidation analysis of reporting entities that are involved with VIEs, and (iv) provide a scope exception for certain entities. Under the new guidance, effective January 1, 2016, the Operating Partnership was determined to be a VIE of the Company as the Operating Partnership is a limited partnership in which the common limited partners do not have substantive kick-out rights or participating rights. However, given that the Company was deemed to be the primary beneficiary of the Operating Partnership because the Company has the ability to control the activities that most significantly impact the Operating Partnership's economic performance, the adoption of this new guidance and the conclusion that the Operating Partnership was a VIE did not have any impact on our consolidated financial statements since the conclusion to consolidate the Operating Partnership still applied. The Operating Partnership was the only new VIE identified as part of the adoption of the guidance as of January 1, 2016. At December 31, 2016 the consolidated financial statements of the Company included three VIEs in addition to the Operating Partnership: 303 Second LLC; 100 First LLC; and an entity established during the fourth quarter of 2016 to facilitate a Section 1031 Exchange. At December 31, 2016 , the Company and the Operating Partnership were determined to be the primary beneficiary of these three VIEs as since we had the ability to control the activities that most significantly impact each of the VIEs’ economic performance. As of December 31, 2016 , the three VIEs’ total assets, liabilities and noncontrolling interest included on our consolidated balance sheet were approximately $654.3 million (of which $588.6 million related to real estate held for investment), approximately $166.1 million and approximately $124.3 million , respectively. Revenues, income and net assets generated by 303 Second LLC and 100 First LLC may only be used to settle their contractual obligations, which primarily consist of operating expenses, mortgage debt related payments, capital expenditures and required distributions. In January 2017, the Section 1031 Exchange was successfully completed and the entity established for the 1031 Exchange was no longer a VIE. At December 31, 2015 , the consolidated financial statements of the Company and the Operating Partnership included two VIEs in which we were deemed to be the primary beneficiary. One VIE, Redwood LLC, was established in the second quarter of 2013 in connection with an undeveloped land acquisition. During the year ended December 31, 2016 , Redwood LLC had a VIE reconsideration event and was determined to no longer be a VIE. The other VIE was established during the fourth quarter of 2015 to facilitate potential Section 1031 Exchanges and was terminated during 2016. The impact of consolidating the VIEs increased the Company’s total assets, liabilities and noncontrolling interests as of December 31, 2015 by approximately $203.3 million (of which $187.3 million related to real estate held for investment on our consolidated balance sheet), approximately $28.8 million and approximately $6.5 million , respectively. Our accounting policy is to consolidate entities in which we have a controlling financial interest and significant decision making control over the entity's operations. In determining whether we have a controlling financial interest in a partially owned entity and the requirement to consolidate the accounts of that entity, we consider factors such as ownership interest, board representation, management representation, size of our investment (including loans), authority to control decisions, and contractual and substantive participating rights of the members. In addition to evaluating control rights, we consolidate entities in which the other members have no substantive kick-out rights to remove the Company as the managing member. We also evaluate whether the entity is a variable interest entity and whether we are the primary beneficiary. VIEs are entities in which the equity investors do not have sufficient equity at risk to finance their endeavors without additional financial support or the holders of the equity investment at risk do not have a controlling financial interest. We are deemed to be the primary beneficiary of a VIE when we have the power to direct the activities of the VIE that most significantly impact the VIEs’ economic performance and the obligation to absorb losses or receive benefits that could potentially be significant to the VIE. If the requirements for consolidation are not met, the Company would account for investments under the equity method of accounting if we have the ability to exercise significant influence over the entity. Equity method investments would be initially recorded at cost and subsequently adjusted for our share of net income or loss and cash contributions and distributions each period. The Company did not have any equity method investments at December 31, 2016 or December 31, 2015 .
Acquisitions	Acquisitions We record the acquired tangible and intangible assets and assumed liabilities of acquisitions of operating properties and development and redevelopment opportunities that meet the accounting criteria to be accounted for as business combinations at fair value at the acquisition date. The acquired assets and assumed liabilities for an acquisition generally include but are not limited to (i) land and improvements, buildings and improvements, undeveloped land and construction in progress and (ii) identified tangible and intangible assets and liabilities associated with in-place leases, including tenant improvements, leasing costs, value of above-market and below-market operating leases and ground leases, acquired in-place lease values and tenant relationships, if any. Any debt assumed and equity (including common units of the Operating Partnership) issued in connection with a property acquisition is recorded at fair value on the date of acquisition. The fair value of land and improvements is derived from comparable sales of land and improvements within the same submarket and/or region. The fair value of buildings and improvements, tenant improvements and leasing costs considers the value of the property as if it was vacant as well as current replacement costs and other relevant market rate information. The fair value of the above-market or below-market component of an acquired in-place operating lease is based upon the present value (calculated using a market discount rate) of the difference between (i) the contractual rents to be paid pursuant to the lease over its remaining non-cancellable lease term and (ii) our estimate of the rents that would be paid using fair market rental rates and rent escalations at the date of acquisition measured over the remaining non-cancellable term of the lease for above-market operating leases and the initial non-cancellable term plus the term of any below-market fixed rate renewal options, if applicable, for below-market operating leases. Our below-market operating leases generally do not include fixed rate or below-market renewal options. The amounts recorded for above-market operating leases are included in deferred leasing costs and acquisition-related intangible assets, net on the balance sheet and are amortized on a straight-line basis as a reduction of rental income over the remaining term of the applicable leases. The amounts recorded for below-market operating leases are included in deferred revenue and acquisition-related intangible liabilities, net on the balance sheet and are amortized on a straight-line basis as an increase to rental income over the remaining term of the applicable leases plus the term of any below-market fixed rate renewal options, if applicable. The amortization of the below-market ground lease obligation is recorded as an increase to ground lease expense in the consolidated statements of operations for the periods presented. The amortization of the above-market ground lease obligation is recorded as a decrease to ground lease expense in the consolidations statements of operations for the periods presented. The fair value of acquired in-place leases is derived based on our assessment of lost revenue and costs incurred for the period required to lease the “assumed vacant” property to the occupancy level when purchased. The amount recorded for acquired in-place leases is included in deferred leasing costs and acquisition-related intangible assets, net on the balance sheet and amortized as an increase to depreciation and amortization expense over the remaining term of the applicable leases. Fully amortized intangible assets are written off each quarter. We record the acquisition of undeveloped land that does not meet the accounting criteria to be accounted for as business combinations and the subsequent acquisition of the fee interest in land and improvements underlying our properties at the purchase price paid and capitalize the associated acquisition costs. During the years ended December 31, 2016 , 2015 and 2014 we capitalized $0.5 million , $1.1 million and $4.5 million , respectively, in acquisition costs associated with development acquisitions.
Operating Properties, Cost Capitalization, and Depreciations and Amortization of Buildings and Improvements	Operating Properties Operating properties are generally carried at historical cost less accumulated depreciation. Properties held for sale are reported at the lower of the carrying value or the fair value less estimated cost to sell. The cost of operating properties includes the purchase price or development costs of the properties. Costs incurred for the renovation and betterment of the operating properties are capitalized to our investment in that property. Maintenance and repairs are charged to expense as incurred. When evaluating properties to be held and used for potential impairment, we first evaluate whether there are any indicators of impairment for any of our properties. If any impairment indicators are present for a specific property, we then perform an undiscounted cash flow analysis and compare the net carrying amount of the property to the property’s estimated undiscounted future cash flow over the anticipated holding period. If the estimated undiscounted future cash flow is less than the net carrying amount of the property, we then perform an impairment loss calculation to determine if the fair value of the property is less than the net carrying value of the property. Our impairment loss calculation compares the net carrying amount of the property to the property’s estimated fair value, which may be based on estimated discounted future cash flow calculations or third-party valuations or appraisals. We would recognize an impairment loss if the asset’s net carrying amount exceeds the asset’s estimated fair value. If we were to recognize an impairment loss, the estimated fair value of the asset (less costs to sell for assets held for sale) would become its new cost basis. For a depreciable long-lived asset, the new cost basis would be depreciated (amortized) over the remaining useful life of that asset. Cost Capitalization All costs clearly associated with the development, redevelopment and construction of a property are capitalized as project costs, including internal compensation costs. In addition, the following costs are capitalized as project costs during periods in which activities necessary to prepare development and redevelopment properties for its intended use are in progress: pre-construction costs essential to the development of the property, interest, real estate taxes and insurance. • For office development and redevelopment properties that are pre-leased, we cease capitalization when revenue recognition commences, which is upon substantial completion of tenant improvements deemed to be the Company's asset for accounting purposes. • For office development and redevelopment properties that are not pre-leased, we may not immediately build out the tenant improvements. Therefore, we cease capitalization when revenue recognition commences upon substantial completion of the tenant improvements deemed to be the Company's asset for accounting purposes, but in any event, no later than one year after the cessation of major construction activities. We also cease capitalization on a development or redevelopment property when activities necessary to prepare the property for its intended use have been suspended. • For office development or redevelopment properties with multiple tenants and staged leasing, we cease capitalization and begin depreciation on the portion of the development or redevelopment property for which revenue recognition has commenced. • For residential development properties, we cease capitalization when the property is substantially complete and available for occupancy. Once major construction activity has ceased and the development or redevelopment property is in the lease-up phase, the costs capitalized to construction in progress are transferred to land and improvements, buildings and improvements, and deferred leasing costs on our consolidated balance sheets as the historical cost of the property. Depreciation and Amortization of Buildings and Improvements The costs of buildings and improvements and tenant improvements are depreciated using the straight-line method of accounting over the estimated useful lives set forth in the table below.
Discontinued Operations and Properties Held for Sale	Real Estate Assets Held for Sale, Dispositions and Discontinued Operations A real estate asset is classified as held for sale when certain criteria are met, including but not limited to the availability of the asset for immediate sale, the existence of an active program to locate a buyer and the probable sale or transfer of the asset within one year. If such criteria are met, we present the applicable assets and liabilities related to the real estate asset held for sale, if material, separately on the balance sheet and we would cease to record depreciation and amortization expense. Real estate assets held for sale are reported at the lower of their carrying value or their estimated fair value less the estimated costs to sell. As of December 31, 2016 , we classified one operating property located in San Diego, California as held for sale. As of December 31, 2015 , we classified four operating properties and one undeveloped land parcel located in San Diego, California as held for sale. Effective January 1, 2015, the Company adopted FASB ASU No. 2014-08 (“ASU 2014-08”), which changed the criteria for reporting discontinued operations while enhancing disclosures in this area. Under the new guidance, only property disposals representing a strategic shift that has (or will have) a major effect on an entity's operations and financial results, such as a major line of business, a major geographical area or a major equity investment, are required to be presented as discontinued operations. If we were to determine that the property disposition represents a strategic shift, the revenues, expenses and net gain (loss) on dispositions of the property would be recorded in discontinued operations for all periods presented through the date of the applicable disposition. The Company adopted and applied the new guidance on a prospective basis as required by ASU 2014-08. Therefore, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are presented in continuing operations for all periods presented. In accordance with this guidance, the operations of the six properties sold during the year ended December 31, 2016 and the ten properties sold during the year ended December 31, 2015 are presented in continuing operations for the years ended December 31, 2016 and December 31, 2015 , respectively. Prior to January 1, 2015, the revenues and expenses of operating properties that have been sold, if material, and the revenues and expenses of operating properties that have been classified as held for sale, if material, are reported in the consolidated statements of operations as discontinued operations for all periods presented through the date of the applicable disposition. The net gains (losses) on disposition of operating properties are reported in the consolidated statements of operations as discontinued operations in the period the properties are sold. In determining whether the revenues, expenses, and net gains (losses) on dispositions of operating properties are reported as discontinued operations, we evaluate whether we have any significant continuing involvement in the operations, leasing, or management of the sold property. If we were to determine that we had any significant continuing involvement, the revenues, expenses and net gain (loss) on dispositions of the operating property would not be recorded in discontinued operations. For the year ended December 31, 2014, discontinued operations includes the net income and gains on all of the properties sold in 2014. The net gains (losses) on dispositions of non-depreciable real estate property, including land, are reported in the consolidated statements of operations as gains (losses) on sale of land within continuing operations in the period the land is sold
Revenue Recognition, Tenant Reimbursements and Other Property Income	Revenue Recognition We recognize revenue from rent, tenant reimbursements, parking and other revenue once all of the following criteria are met: (i) the agreement has been fully executed and delivered, (ii) services have been rendered, (iii) the amount is fixed or determinable and (iv) the collectability of the amount is reasonably assured. Minimum annual rental revenues are recognized in rental revenues on a straight-line basis over the term of the related lease. Rental revenue recognition commences when the tenant takes possession or controls the physical use of the leased space. In order for the tenant to take possession, the leased space must be substantially complete and ready for its intended use. In order to determine whether the leased space is substantially ready for its intended use, we begin by determining whether the Company or the tenant owns the tenant improvements. When we conclude that the Company is the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is generally when Company owned tenant improvements are substantially complete. In certain instances, when we conclude that the Company is not the owner (the tenant is the owner) of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space. When we conclude that the Company is the owner of tenant improvements, we record the cost to construct the tenant improvements, including costs paid for or reimbursed by the tenants, as a capital asset. For these tenant improvements, we record the amount funded by or reimbursed by the tenants as deferred revenue, which is amortized on a straight-line basis as additional rental income over the term of the related lease. When we conclude that the tenant is the owner of tenant improvements for accounting purposes, we record our contribution towards those improvements as a lease incentive, which is included in deferred leasing costs and acquisition-related intangible assets, net on our consolidated balance sheets and amortized as a reduction to rental income on a straight-line basis over the term of the lease. For residential properties, we commence revenue recognition upon occupancy of the units by the tenants. Residential rental revenue is recognized on a straight-line basis over the term of the related lease, net of any concessions. Tenant Reimbursements Reimbursements from tenants, consisting of amounts due from tenants for common area maintenance, real estate taxes and other recoverable costs, are recognized as revenue in the period the recoverable costs are incurred. Tenant reimbursements are recognized and recorded on a gross basis, as we are generally the primary obligor with respect to purchasing goods and services from third-party suppliers, have discretion in selecting the supplier, and have credit risk. Other Property Income Other property income primarily includes amounts recorded in connection with lease terminations, tenant bankruptcy settlement payments and property damage settlement related payments. Lease termination fees are amortized over the remaining lease term, if applicable. If there is no remaining lease term, they are recognized when received and realized. Other property income also includes miscellaneous income from tenants, such as fees related to the restoration of leased premises to their original condition and fees for late rental payments.
Allowances for Uncollectible Tenant and Deferred Rent Receivables	Allowances for Uncollectible Tenant and Deferred Rent Receivables We carry our current and deferred rent receivables net of allowances for uncollectible amounts. Our determination of the adequacy of these allowances is based primarily upon evaluations of individual receivables, current economic conditions, and other relevant factors. The allowances are increased or decreased through the provision for bad debts on our consolidated statements of operations.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly-liquid investments with original maturities of three months or less to be cash equivalents
Restricted Cash	Restricted Cash Restricted cash consists of cash proceeds from dispositions that are temporarily held at qualified intermediaries for purposes of facilitating potential Section 1031 Exchanges and cash held in escrow related to acquisition and disposition holdbacks. Restricted cash also includes cash held as collateral to provide credit enhancement for the Operating Partnership’s mortgage debt, including cash reserves for capital expenditures, tenant improvements and property taxes. As of December 31, 2016 , we had $48.4 million of restricted cash held at qualified intermediaries for the purpose of facilitating Section 1031 Exchanges. In January 2017, the Section 1031 Exchange was completed and the cash was released from the qualified intermediary. As of December 31, 2015 , we had no restricted cash held at qualified intermediaries for the purpose of facilitating Section 1031 Exchanges.
Marketable Securities	Marketable Securities / Deferred Compensation Plan Marketable securities reported in our consolidated balance sheets represent the assets held in connection with the Kilroy Realty Corporation 2007 Deferred Compensation Plan (the “Deferred Compensation Plan”) (see Note 16 “Employee Benefit Plans” for additional information). The Deferred Compensation Plan assets are held in a limited rabbi trust and invested in various mutual and money market funds. As a result, the marketable securities are treated as trading securities for financial reporting purposes and are adjusted to fair value at the end of each accounting period, with the corresponding gains and losses recorded in interest income and other net investment gains.
Deferred Compensation Plan	At the time eligible management employees (“Participants”) defer compensation or earn mandatory Company contributions, or if we were to make a discretionary contribution, we record compensation cost and a corresponding deferred compensation plan liability, which is included in accounts payable, accrued expenses, and other liabilities on our consolidated balance sheets. This liability is adjusted to fair value at the end of each accounting period based on the performance of the benchmark funds selected by each Participant, and the impact of adjusting the liability to fair value is recorded as an increase or decrease to compensation cost. The impact of adjusting the deferred compensation plan liability to fair value and the changes in the value of the marketable securities held in connection with the Deferred Compensation Plan generally offset and therefore do not significantly impact net income.
Deferred Leasing Costs	Deferred Leasing Costs Costs incurred in connection with successful property leasing are capitalized as deferred leasing costs and classified as investing activities in the statement of cash flows. Deferred leasing costs consist primarily of leasing commissions and also include certain internal payroll costs and lease incentives, which are amortized using the straight-line method of accounting over the lives of the leases which generally range from one to 20 years. We reevaluate the remaining useful lives of leasing costs as the creditworthiness of our tenants and economic and market conditions change. If we determine that the estimated remaining life of a lease has changed, we adjust the amortization period accordingly. Fully amortized deferred leasing costs are written off each quarter.
Deferred Financing Costs, Debt Discounts and Premiums, Exchangeable Debt Instruments, and Gain and Losses on Early Extinguishment of Debt	Deferred Financing Costs Financing costs related to the origination or assumption of long-term debt are deferred and generally amortized using the straight-line method of accounting, which approximates the effective interest method, over the contractual terms of the applicable financings. Fully amortized deferred financing costs are written off when the corresponding financing is repaid. As of December 31, 2016 and 2015 , our secured debt was reported net of unamortized deferred financing costs of $1.4 million and $1.1 million , respectively, and our unsecured debt was reported net of unamortized deferred financing costs of $10.1 million and $12.0 million , respectively. Deferred financing costs related to our unsecured line of credit were reported in prepaid expenses and other assets net of accumulated amortization of $5.7 million and $4.3 million as of December 31, 2016 and 2015 , respectively. Debt Discounts and Premiums Original issuance debt discounts and discounts/premiums related to recording debt acquired in connection with operating property acquisitions at fair value are generally amortized and accreted on a straight-line basis, which approximates the effective interest method. Discounts are recorded as additional interest expense from date of issuance or acquisition through the contractual maturity date of the related debt. Premiums are recorded as a reduction to interest expense from the date of issuance or acquisition through the contractual maturity date of the related debt. Our secured debt is presented including unamortized premiums of $4.4 million and $6.2 million as of December 31, 2016 and 2015 , respectively. Our unsecured senior notes are presented net of unamortized discounts of $6.6 million and $7.4 million , as of December 31, 2016 and 2015 , respectively.
Noncontrolling Interest and Partnership Interests	Noncontrolling Interests - Common Units of the Operating Partnership in the Company's Consolidated Financial Statements Common units of the Operating Partnership within noncontrolling interests in the Company’s consolidated financial statements represent the common limited partnership interests in the Operating Partnership not held by the Company (“noncontrolling common units”). Noncontrolling common units are presented in the equity section of the Company’s consolidated balance sheets and are reported at their proportionate share of the net assets of the Operating Partnership. Noncontrolling interests with redemption provisions that permit the issuer to settle in either cash or shares of common stock must be further evaluated to determine whether equity or temporary equity classification on the balance sheet is appropriate. Since the common units contain such a provision, we evaluated the accounting guidance and determined that the common units qualify for equity presentation in the Company’s consolidated financial statements. Net income attributable to noncontrolling common units is allocated based on their relative ownership percentage of the Operating Partnership during the reported period. The noncontrolling interest ownership percentage is determined by dividing the number of noncontrolling common units by the total number of common units outstanding. The issuance or redemption of additional shares of common stock or common units results in changes to the noncontrolling interest percentage as well as the total net assets of the Company. As a result, all equity transactions result in an allocation between equity and the noncontrolling interest in the Company’s consolidated balance sheets and statements of equity to account for the changes in the noncontrolling interest ownership percentage as well as the change in total net assets of the Company. Noncontrolling Interests in Consolidated Property Partnerships Noncontrolling interests in consolidated property partnerships represent the equity interests held by unrelated third parties in our three consolidated property partnerships (see Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements” and see Note 12 “Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements”). Noncontrolling interests in consolidated property partnerships are not redeemable and are presented as permanent equity in the Company's consolidated balance sheets. We account for the noncontrolling interests in consolidated property partnerships using the hypothetical liquidation at book value (“HLBV”) method to attribute the earnings or losses of the consolidated property partnerships between the controlling and noncontrolling interests. Under the HLBV method, the amounts reported as noncontrolling interests in consolidated property partnerships in the consolidated balance sheets represent the amounts the noncontrolling interests would hypothetically receive at each balance sheet reporting date under the liquidation provisions of the governing agreements assuming the net assets of the consolidated property partnerships were liquidated at recorded amounts and distributed between the controlling and noncontrolling interests in accordance with the governing documents. The net income attributable to noncontrolling interests in consolidated property partnerships in the consolidated statements of operations is associated with the increase or decrease in the noncontrolling interest holders’ contractual claims on the respective entities’ balance sheets assuming a hypothetical liquidation at the end of that reporting period when compared with their claims on the respective entities’ balance sheets assuming a hypothetical liquidation at the beginning of that reporting period, after removing any contributions or distributions. Preferred Partnership Interests on the Operating Partnership’s Consolidated Balance Sheets Preferred partnership interests of the Operating Partnership represent the issued and outstanding 4,000,000 6.875% Series G Cumulative Redeemable Preferred Units (“Series G Preferred Units”) and the 4,000,000 6.375% Series H Cumulative Redeemable Preferred Units (“Series H Preferred Units”) which were outstanding as of December 31, 2016 and 2015 . The Series G and Series H Preferred Units are presented in the permanent equity section of the Operating Partnership’s consolidated balance sheets given that the Series G and Series H Preferred Units may only be redeemed at our option (see Note 14 “Preferred and Common Units of the Operating Partnership”). The Company is the holder of both the Series G and Series H Preferred Units and for each Series G and Series H Preferred Unit the Company has an equivalent number of shares of the Company’s 6.875% Series G Cumulative Redeemable Preferred Stock and shares of the Company’s 6.375% Series H Cumulative Redeemable Preferred Stock publicly issued and outstanding.
Equity Offerings	Equity Offerings Underwriting commissions and offering costs incurred in connection with common equity offerings and our at-the-market stock offering program (see Note 13 “Stockholders’ Equity of the Company”) are reflected as a reduction of additional paid-in capital. Issuance costs incurred in connection with preferred equity offerings are reflected as a reduction of the carrying value of the preferred equity. The Company records preferred stock issuance costs as a non-cash preferred equity distribution at the time we notify the holders of preferred stock or units of our intent to redeem such shares or units. The net proceeds from any equity offering of the Company are generally contributed to the Operating Partnership in exchange for a number of common or preferred units equivalent to the number of shares of common or preferred stock issued and are reflected in the Operating Partnership’s consolidated financial statements as an increase in partners’ capital.
Share-based Incentive Compensation Accounting	Share-based Incentive Compensation Accounting Compensation cost for all share-based awards, including options, requires measurement at estimated fair value on the grant date. Compensation cost is recognized over the service vesting period, which represents the requisite service period, on a straight-line basis. The grant date fair value of market measure-based share-based compensation plans are calculated using a Monte Carlo simulation pricing model. The grant date fair value of stock option grants is calculated using the Black-Scholes valuation model. Equity awards settled in cash are valued at the fair value of our common stock on the period end date through the settlement date. Equity awards settled in cash are remeasured at each reporting period and are recognized as a liability in the consolidated balance sheet during the vesting period until settlement. For share-based awards in which the performance period precedes the grant date, we recognize compensation cost over the requisite service period, which includes both the performance and service vesting periods, using the accelerated attribution expense method. The requisite service period begins on the date the Executive Compensation Committee authorizes the award and adopts any relevant performance measures. For programs with performance-based measures, the total estimated compensation cost is based on our most recent estimate of the probable achievement of the pre-established specific corporate performance measures. These estimates are based on our latest internal forecasts for each performance measure. For programs with market measures, the total estimated compensation cost is based on the fair value of the award at the grant date. For programs with performance-based measures and market measures, the total estimated compensation cost is based on the fair value per share at the grant date multiplied by our most recent estimate of the number of shares to be earned based on the probable achievement of the pre-established corporate performance measures based on our latest internal forecasts. In accordance with the provisions of our share-based incentive compensation plans, we accept the return of shares of Company common stock, at the current quoted market price, from employees to satisfy minimum statutory tax-withholding requirements related to shares that vested during the period. For share based awards granted by the Company, the Operating Partnership issues a number of common units equal to the number of shares of common stock ultimately granted by the Company in respect of such awards.
Basic and Diluted Net Income (Loss)	Basic and Diluted Net Income Available to Common Stockholders per Share Basic net income available to common stockholders per share is computed by dividing net income available to common stockholders, after preferred distributions and the allocation of income to participating securities, by the weighted-average number of shares of common stock outstanding for the period. Diluted net income available to common stockholders per share is computed by dividing net income available for common stockholders, after preferred distributions and the allocation of income to participating securities, by the sum of the weighted-average number of shares of common stock outstanding for the period plus the assumed exercise of all dilutive securities. The impact of the outstanding common units is considered in the calculation of diluted net income available to common stockholders per share. The common units are not reflected in the diluted net income available to common stockholders per share calculation because the exchange of common units into common stock is on a one for one basis, and the common units are allocated net income on a per share basis equal to the common stock (see Note 22 “Net Income Available to Common Stockholders Per Share of the Company”). Accordingly, any exchange would not have any effect on diluted net income (loss) available to common stockholders per share. Nonvested share-based payment awards (including nonvested restricted stock units (“RSUs”), vested market-measure RSUs and vested dividend equivalents issued to holders of RSUs) containing nonforfeitable rights to dividends or dividend equivalents are accounted for as participating securities and included in the computation of basic and diluted net income available to common stockholders per share pursuant to the two-class method. The dilutive effect of stock options is reflected in the weighted average diluted outstanding shares calculation by application of the treasury stock method. The dilutive effect of the outstanding nonvested shares of common stock (“nonvested shares”) and RSUs that have not yet been granted but are contingently issuable under the share-based compensation programs is reflected in the weighted average diluted shares calculation by application of the treasury stock method at the beginning of the quarterly period in which all necessary conditions have been satisfied.
Fair Value Measurements	Fair Value Measurements The fair value of our financial assets and liabilities are disclosed in Note 19, “Fair Value Measurements and Disclosures,” to our consolidated financial statements. The only financial assets recorded at fair value on a recurring basis in our consolidated financial statements are our marketable securities. We elected not to apply the fair value option for any of our eligible financial instruments or other items. We determine the estimated fair value of financial assets and liabilities utilizing a hierarchy of valuation techniques based on whether the inputs to a fair value measurement are considered to be observable or unobservable in a marketplace. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect our market assumptions. This hierarchy requires the use of observable market data when available. The following is the fair value hierarchy: • Level 1 – quoted prices for identical instruments in active markets; • Level 2 – quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active and model-derived valuations in which significant inputs and significant value drivers are observable in active markets; and • Level 3 – fair value measurements derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. We determine the fair value for the marketable securities using quoted prices in active markets for identical assets. Our other financial instruments, which are only disclosed at fair value, are comprised of secured debt, unsecured senior notes, unsecured line of credit and unsecured term loan facility. We generally determine the fair value of our secured debt, unsecured debt, and unsecured line of credit by performing discounted cash flow analyses using an appropriate market discount rate. We calculate the market rate by obtaining period-end treasury rates for maturities that correspond to the maturities of our fixed-rate debt and then adding an appropriate credit spread based on information obtained from third-party financial institutions. These credit spreads take into account factors, including but not limited to, our credit profile, the tenure of the debt, amortization period, whether the debt is secured or unsecured, and the loan-to-value ratio of the debt to the collateral. These calculations are significantly affected by the assumptions used, including the discount rate, credit spreads and estimates of future cash flow. We calculate the market rate of our unsecured line of credit, unsecured term loan facility, and unsecured term loan by obtaining the period-end London Interbank Offered Rate (“LIBOR”) and then adding an appropriate credit spread based on our credit ratings, and the amended terms of our unsecured line of credit, unsecured term loan facility, and unsecured term loan agreement. We determine the fair value of each of our publicly traded unsecured senior notes based on their quoted trading price at the end of the reporting period, if such prices are available. Carrying amounts of our cash and cash equivalents, restricted cash and accounts payable approximate fair value due to their short-term maturities.
Income Taxes	Income Taxes We have elected to be taxed as a REIT under Sections 856 through 860 of the Code. To qualify as a REIT, we must distribute annually at least 90% of our adjusted taxable income, as defined in the Code, to our stockholders and satisfy certain other organizational and operating requirements. We generally will not be subject to federal income taxes if we distribute 100% of our taxable income for each year to our stockholders. If we fail to qualify as a REIT in any taxable year, we will be subject to federal income taxes (including any applicable alternative minimum tax) on our taxable income at regular corporate rates and we may not be able to qualify as a REIT for four subsequent taxable years. Even if we qualify for taxation as a REIT, we may be subject to certain state and local taxes on our income and property and to federal income taxes and excise taxes on our undistributed taxable income. We believe that we have met all of the REIT distribution and technical requirements for the years ended December 31, 2016 , 2015 and 2014 , and we were not subject to any federal income taxes (see Note 26 “Tax Treatment of Distributions” for additional information). We intend to continue to adhere to these requirements and maintain the Company’s REIT status. Accordingly, no provision for income taxes has been made in the accompanying financial statements. In addition, any taxable income from our taxable REIT subsidiary, which was formed in 2002, is subject to federal, state, and local income taxes. For the years ended December 31, 2016 , 2015 and 2014 the taxable REIT subsidiary had de minimis taxable income.
Uncertain Tax Positions	Uncertain Tax Positions We include favorable tax positions in the calculation of tax liabilities if it is more likely than not that our adopted tax position will prevail if challenged by tax authorities. We evaluated the potential impact of identified uncertain tax positions for all tax years still subject to audit under state and federal income tax law and concluded that we did not have any unrecognized tax benefits or any additional tax liabilities as of December 31, 2016 or 2015 . As of December 31, 2016 , the years still subject to audit are 2012 through 2016 under the California state income tax law and 2013 through 2016 under the federal income tax law.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported periods. Actual results could differ from those estimates.
Segment	Segment We currently operate in one operating segment, our office properties segment.
Concentration of Credit Risk	Concentration of Credit Risk All of our properties and development and redevelopment projects are owned and all of our business is currently conducted in the state of California with the exception of the ownership and operation of twelve office properties and one near-term development project located in the state of Washington. The ability of tenants to honor the terms of their leases is dependent upon the economic, regulatory, and social factors affecting the communities in which our tenants operate. As of December 31, 2016 , our 15 largest tenants represented approximately 37.3% of total annualized base rental revenues. We have deposited cash with financial institutions that is insured by the Federal Deposit Insurance Corporation (“FDIC”) up to $250,000 per institution. As of December 31, 2016 and 2015 , we had cash accounts in excess of FDIC insured limits.
Recent Accounting Pronouncements	Recently Issued Accounting Pronouncements On January 5, 2017, the FASB issued ASU No. 2017-01 (“ASU 2017-01”) to amend the guidance for determining whether a transaction involves the purchase or disposal of a business or an asset. The amendments clarify that when substantially all of the fair value of the gross assets acquired or disposed of is concentrated in a single identifiable asset or a group of similar assets, the set of assets and activities is not a business. ASU 2017-01 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years and early adoption is permitted for transactions which have not been previously reported in financial statements that have been issued. The Company currently anticipates that it will early adopt the guidance effective January 1, 2017 and that the guidance will result in acquisitions of operating properties being accounted for as asset acquisitions instead of business combinations. The adoption of this guidance will also change the accounting for the transaction costs for acquisitions of operating properties such that transaction costs will be able to be capitalized as part of the purchase price of the acquisition instead of being expensed as acquisition-related expenses. On November 17, 2016, the FASB issued ASU No. 2016-18 (“ASU 2016-18”) to require that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents will be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years and early adoption is permitted. The Company does not currently anticipate that the guidance will have a material impact on our consolidated financial statements or notes to our consolidated financial statements. On August 26, 2016, the FASB issued ASU No. 2016-15 (“ASU 2016-15”) to provide guidance for areas where there is diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company does not currently anticipate that the guidance will have a material impact on our consolidated financial statements or notes to our consolidated financial statements. On June 16, 2016, the FASB issued ASU No. 2016-13 (“ASU 2016-13”) to amend the accounting for credit losses for certain financial instruments. Under the new guidance, an entity recognizes its estimate of expected credit losses as an allowance, which the FASB believes will result in more timely recognition of such losses. ASU 2016-13 is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company does not currently anticipate that the guidance will have a material impact on our consolidated financial statements or notes to our consolidated financial statements. On May 9, 2016, the FASB issued ASU No. 2016-12, which clarifies and provides practical expedients for certain aspects of ASU No. 2014-09, which outlines a single comprehensive model for entities to use in accounting for revenues arising from contracts with customers and notes that lease contracts with customers are a scope exception. Public business entities may elect to adopt the amendments as of the original effective date; however, adoption is required for annual reporting periods beginning after December 15, 2017. The Company is currently conducting its evaluation of the impact of the guidance. More specifically, the Company is evaluating the impact on the timing of gain recognition for dispositions, but currently does not believe there will be a material impact to our consolidated financial statements for dispositions given the simplicity of the Company’s historical disposition transactions. In addition, the Company is in the process of evaluating whether the guidance will impact the accounting for tenant reimbursements, but we currently do not believe this will have a material impact on our consolidated financial statements and notes to our consolidated financial statements. On March 30, 2016, the FASB issued ASU No. 2016-09 (“ASU 2016-09”) to amend the accounting guidance for share-based payment accounting. The areas for simplification in ASU 2016-09 involve several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for annual periods beginning after December 15, 2016 and interim periods within those annual periods and early adoption is permitted. The Company adopted this guidance effective January 1, 2017 and the adoption did not have a material impact on our consolidated financial statements or notes to our consolidated financial statements. On February 25, 2016, the FASB issued ASU No. 2016-02 (“ASU 2016-02”) to amend the accounting guidance for leases. The accounting applied by a lessor is largely unchanged under ASU 2016-02. However, the standard requires lessees to recognize lease assets and lease liabilities for leases classified as operating leases on the balance sheet. Lessees will recognize in the statement of financial position a liability to make lease payments and a right-of-use asset representing its right to use the underlying asset for the lease term. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it will recognize lease expense for such leases generally on a straight-line basis over the lease term. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018 and early adoption is permitted. The Company is currently conducting its evaluation of the impact of the guidance. The Company currently believes that the adoption of the standard will not have a material impact for leases where it is a lessor. However, for leases where the Company is a lessee, specifically for the Company’s ground leases, the Company has preliminarily concluded that the adoption of the standard will have a material impact on its consolidated balance sheets since both existing ground leases and any future ground leases will be recorded on the Company's consolidated balance sheet as an obligation of the Company. In addition, for new ground leases entered into after the adoption date of the new standard, the Company currently believes such leases may be required to be accounted for as a financing type lease resulting in ground lease expense recorded using the effective interest method instead of on a straight line basis over the term of the lease. The Company currently believes this could have a material impact on the Company’s results of operations if it entered into material new ground leases after the date of adoption since ground lease expense calculated using the effective interest method results in an increased amount of ground lease expense in the earlier years of a ground lease as compared to the current straight line method. On January 5, 2016, the FASB issued ASU No. 2016-01 (“ASU 2016-01”) to amend the accounting guidance on the classification and measurement of financial instruments. The standard requires that all investments in equity securities, including other ownership interests, are carried at fair value through net income. This requirement does not apply to investments that qualify for equity method accounting or to those that result in consolidation of the investee or for which the entity has elected the predictability exception to fair value measurement. Additionally, the standard requires that the portion of the total fair value change caused by a change in instrument-specific credit risk for financial liabilities for which the fair value option has been elected would be recognized in other comprehensive income. Any accumulated amount remaining in other comprehensive income is reclassified to earnings when the liability is extinguished. ASU 2016-01 is effective for fiscal years beginning after December 15, 2017. The Company does not currently anticipate that the guidance will have a material impact on our consolidated financial statements or notes to our consolidated financial statements.
Kilroy Realty, L.P. [Member]
Basis of presentation and significant accounting policies [Line Items]
Noncontrolling Interest and Partnership Interests	Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements Noncontrolling interests in the Operating Partnership’s consolidated financial statements include the non-controlling interest in property partnerships (see Note 12 “Noncontrolling Interests on the Operating Partnership’s Consolidated Financial Statements”) and the Company’s 1.0% general partnership interest in the Finance Partnership. The 1.0% general partnership interest in the Finance Partnership noncontrolling interest is presented in the permanent equity section of the Operating Partnership’s consolidated balance sheets given that these interests are not convertible or redeemable into any other ownership interest of the Company or the Operating Partnership. Common Partnership Interests on the Operating Partnership’s Consolidated Balance Sheets The common units held by the Company and the noncontrolling common units held by the common limited partners are both presented in the permanent equity section of the Operating Partnership’s consolidated balance sheets in partners’ capital. The redemption rights of the noncontrolling common units permit us to settle the redemption obligation in either cash or shares of the Company’s common stock at our option (see Note 11 “Noncontrolling Interests on the Company’s Consolidated Financial Statements” for additional information).
Basic and Diluted Net Income (Loss)	Basic and Diluted Net Income Available to Common Unitholders per Unit Basic net income available to common unitholders per unit is computed by dividing net income available to common unitholders, after preferred distributions and the allocation of income to participating securities, by the weighted-average number of vested common units outstanding for the period. Diluted net income available to common unitholders per unit is computed by dividing net income available to common unitholders, after preferred distributions and the allocation of income to participating securities, by the sum of the weighted-average number of common units outstanding for the period plus the assumed exercise of all dilutive securities. The dilutive effect of stock options, outstanding nonvested shares, RSUs, and awards containing nonforfeitable rights to dividend equivalents are reflected in diluted net income available to common unitholders per unit in the same manner as noted above for net income available to common stockholders per share.

Organization and Ownership (Tab

Organization and Ownership (Tables)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of real estate properties	Number of Properties/Projects Estimated Office Rentable Square Feet (unaudited) Properties held for sale (1) 1 67,995 Development project in “ lease-up" (2) 1 377,000 Development projects under construction (2)(3) 3 1,100,000 _______________ (1) See Note 4 “Dispositions and Real Estate Assets Held for Sale” for additional information. (2) Estimated rentable square feet upon completion. (3) Development projects under construction also include 96,000 square feet of retail space and 237 residential units in addition to the estimated office rentable square feet noted above. Our stabilized portfolio of operating properties was comprised of the following properties at December 31, 2016 : Number of Buildings Rentable Square Feet (unaudited) Number of Tenants Percentage Occupied (unaudited) Percentage Leased (unaudited) Stabilized Office Properties 108 14,025,856 549 96.0 % 97.0 % Number of Number of Units Percentage Occupied (unaudited) Percentage Leased (unaudited) Stabilized Residential Property 1 200 46.0 % 56.5 %

Basis of Presentation and Sig47

Basis of Presentation and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Basis of Presentation and Significant Accounting Policies [Abstract]
Buildings, improvements, and tenant improvements depreciation	Asset Description Depreciable Lives Buildings and improvements 25 – 40 years Tenant improvements 1 – 20 years (1) ________________________ (1) Tenant improvements are amortized over the shorter of the lease term or the estimated useful life.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Schedule of Acquisitions	Property Date of Acquisition Number of Buildings Rentable Square Feet (unaudited) Occupancy as of December 31, 2016 (unaudited) Purchase Price (in millions) (1) 2016 Acquisitions 1290-1300 Terra Bella Avenue, Mountain View, CA (2) June 8, 2016 1 114,175 100.0% $ 55.4 8560-8590 West Sunset Blvd., West Hollywood, CA (3) December 7, 2016 4 178,699 87.5% 209.2 1701 Page Mill Rd. and 3150 Porter Dr., Palo Alto, CA (4) December 19, 2016 2 165,585 100.0% 130.0 Total (5) 7 458,459 $ 394.6 ________________________ (1) Excludes acquisition-related costs and non-lease related accrued liabilities assumed. Includes assumed unpaid leasing commissions and tenant improvements. (2) In connection with this acquisition, the Company assumed $0.2 million in accrued liabilities that are not included in the purchase price above. (3) This acquisition encompasses a 10-story office tower, three retail buildings, a four-level subterranean parking structure and three billboards. As of December 31, 2016 , this property was temporarily being held in a separate VIE to facilitate potential Section 1031 Exchanges. During January 2017, the Company closed out the Section 1031 Exchange related to this VIE. See Note 2 “Basis of Presentation and Significant Accounting Policies.” In connection with this acquisition, the Company assumed $0.1 million in accrued liabilities that are not included in the purchase price above. (4) In connection with this acquisition, the Company entered into a long-term ground lease expiring in December 2067. (5) The results of operations for the properties acquired during 2016 contributed $5.2 million and $1.7 million to revenue and net income from continuing operations, respectively, for the year ended December 31, 2016 . During the year ended December 31, 2015 we acquired the following undeveloped land sites listed below from unrelated third parties: Project Date of Acquisition City/Submarket Type Purchase Price (1) (in millions) 2015 Acquisitions 333 Dexter (2) February 13, 2015 Seattle, WA Land $ 49.5 100 Hooper (3) July 7, 2015 San Francisco, CA Land 78.0 Total $ 127.5 _______________ (1) See Note 18 “Commitments and Contingencies” for additional information on certain accrued liabilities for these acquisitions. (2) Acquisition comprised of four adjacent parcels in the South Lake Union submarket of Seattle, Washington located at 330 Dexter Avenue North, 333 Dexter Avenue North, 401 Dexter Avenue North, and 400 Aurora Avenue North. In connection with this acquisition, we also assumed $2.4 million in accrued liabilities and acquisition costs that are not included in the purchase price above. (3) Includes the land parcel located at 150 Hooper. In connection with this acquisition, we assumed $4.1 million in accrued liabilities and acquisition costs that are not included in the purchase price above.
Schedule of estimated fair values of the assets acquired and liabilities assumed	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the respective acquisition dates for our 2016 operating property acquisitions: Acquisitions Total 2016 Acquisitions (1) Assets (in thousands) Land and improvements $ 120,110 Buildings and improvements (2) 259,301 Deferred leasing costs and acquisition-related intangible assets (3) 33,529 Total assets acquired 412,940 Liabilities Accounts payable, accrued expenses and other liabilities 1,122 Deferred revenue and acquisition-related intangible liabilities (4) 18,050 Total liabilities assumed 19,172 Net assets and liabilities acquired $ 393,768 _______________ (1) The purchase price of the three acquisitions completed during the year ended December 31, 2016 were individually less than 5% and in aggregate less than 10% of the Company’s total assets as of December 31, 2015 . (2) Represents buildings, building improvements and tenant improvements. (3) Represents in-place leases (approximately $27.1 million with a weighted average amortization period of 3.9 years), above-market leases (approximately $0.6 million with weighted average amortization period of 15.8 years) and leasing commissions (approximately $5.8 million with a weighted average amortization period of 5.1 years). (4) Represents below-market leases (approximately $18.1 million with a weighted average amortization period of 8.4 years)

Dispositions and Real Estate 49

Dispositions and Real Estate Assets Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of operating property dispositions	The following table summarizes the operating properties sold during the years ended December 31, 2016 , 2015 and 2014 : Location Month of Disposition Number of Buildings Rentable Square Feet (unaudited) Sales Price (in millions) (1) 2016 Dispositions Torrey Santa Fe Properties (2) January 4 465,812 $ 262.3 4930, 4939 & 4955 Directors Place, San Diego, CA (3) July 2 136,908 49.0 Total 2016 Dispositions 6 602,720 $ 311.3 2015 Dispositions 15050 NE 36th Street, Redmond, WA April 1 122,103 $ 51.2 San Diego Properties - Tranches 1 and 2 (4) April/July 9 924,291 258.0 Total 2015 Dispositions 10 1,046,394 $ 309.2 2014 Dispositions (5) San Diego Properties, San Diego, CA (6) January 12 1,049,035 $ 294.7 9785 & 9791 Towne Centre Drive, San Diego, CA June 2 126,000 29.5 111 Pacifica, Irvine, CA September 1 67,496 15.1 4040 Civic Center Drive, San Rafael, CA October 1 130,237 34.9 999 Town & Country Road, Orange, CA December 1 98,551 25.3 Total 2014 Dispositions 17 1,471,319 $ 399.5 __________________ (1) Represents gross sales price before the impact of broker commissions and closing costs. (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe and 7555 Torrey Santa Fe. These properties were classified as held for sale at December 31, 2015 . (3) Includes two operating properties totaling 136,908 rentable square feet and a 7.0 acre undeveloped land parcel. (4) The San Diego Properties - Tranche 1 includes the following properties: 10770 Wateridge Circle, 6200 Greenwich Drive and 6220 Greenwich Drive. The San Diego Properties - Tranche 2 includes the following properties: 6260 Sequence Drive, 6290, Sequence Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive and 4921 Directors Place. (5) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, results of operations for properties disposed of subsequent of January 1, 2015 are presented in continuing operations because they did not represent strategic shifts. Properties disposed of prior to January 1, 2015 are presented in discontinued operations. (6) The San Diego Properties included the following properties: 10020 Pacific Mesa Boulevard, 6055 Lusk Avenue, 5010 and 5005 Wateridge Vista Drive, 15435 and 15445 Innovation Drive, and 15051, 15073, 15231, 15253, 15333 and 15378 Avenue of Science. These properties were held for sale as of December 31, 2013.
Schedule of operating properties and land held for sale	The major classes of assets and liabilities of the properties held for sale as of December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Real estate assets and other assets held for sale (in thousands) Land and improvements $ 2,693 $ 10,534 Buildings and improvements 10,500 144,716 Undeveloped land and construction in progress — 4,824 Total real estate held for sale 13,193 160,074 Accumulated depreciation and amortization (3,900 ) (46,191 ) Total real estate held for sale, net 9,293 113,883 Deferred rent receivables, net — 2,500 Deferred leasing costs and acquisition-related intangible assets, net — 1,115 Prepaid expenses and other assets, net 124 168 Real estate and other assets held for sale, net $ 9,417 $ 117,666 Liabilities and deferred revenue of real estate assets held for sale Secured debt $ — $ 561 Accounts payable, accrued expenses and other liabilities 56 2,497 Deferred revenue and acquisition-related intangible liabilities, net — 2,899 Rents received in advance and tenant security deposits — 1,586 Liabilities and deferred revenue of real estate assets held for sale $ 56 $ 7,543 As of December 31, 2015 , the following land parcel was classified as held for sale: Properties Submarket Gross Site Acreage (unaudited) Sales Price 2015 Held for Sale Carlsbad Oaks - Lot 7 (1) Carlsbad 7.6 $ 4.5 __________________ (1) During the year ended December 31, 2015, the Company recognized a loss relating to selling costs of approximately $0.2 million . As of December 31, 2016 and 2015 , the properties listed below were classified as held for sale. Properties Submarket Property Type Number of Buildings Rentable Square Feet (unaudited) 2016 Held for Sale 5717 Pacific Center Drive (1) Sorrento Mesa Office 1 67,995 2015 Held for Sale Torrey Santa Fe Properties (2)(3) Del Mar Office 4 465,812 __________________ (1) In January 2017, the Company completed the sale of this property for a total sales price of $12.1 million . (2) The Torrey Santa Fe Properties include the following properties: 7525 Torrey Santa Fe, 7535 Torrey Santa Fe, 7545 Torrey Santa Fe, and 7555 Torrey Santa Fe. (3) In January 2016, the Company completed the sale of these properties for a total sales price of $262.3 million .
Schedule of land dispositions	The following table summarizes the land dispositions completed during the years ended December 31, 2016 , 2015 and 2014 : Properties Submarket Month of Disposition Gross Site Acreage (unaudited) Sales Price (1) (in millions) 2016 Land Dispositions Carlsbad Oaks - Lot 7 (2) Carlsbad January 7.6 $ 4.5 Carlsbad Oaks - Lots 4 & 5 Carlsbad June 11.2 6.0 Carlsbad Oaks - Lot 8 Carlsbad June 13.2 8.9 Total 2016 Land Dispositions (3)(4) 32.0 $ 19.4 2015 Land Disposition 17150 Von Karman (4) Irvine January 8.5 $ 26.0 2014 Land Disposition 10850 Via Frontera (4) Rancho Bernardo April 21.0 $ 33.1 __________________ (1) Represents gross sales price before the impact of commissions and closing costs. (2) This land parcel was classified as held for sale as of December 31, 2015. (3) In connection with these land dispositions, $2.3 million of secured debt was assumed by the buyers. See Note 9 “Secured and Unsecured Debt of the Operating Partnership” for additional information. (4) The 2016 land dispositions resulted in a net loss on sales of $0.3 million and the 2015 and 2014 land dispositions resulted in gain on sales of $17.3 million and $3.5 million , respectively. The following table summarizes the revenue and expense components that comprise income from discontinued operations for the year ended December 31, 2014 : 2014 (in thousands) Revenues: Rental income $ 7,206 Tenant reimbursements 278 Other property income 13 Total revenues 7,497 Expenses: Property expenses 2,171 Real estate taxes 692 Depreciation and amortization 2,061 Total expenses 4,924 Income from discontinued operations before net gain on dispositions of discontinued operations 2,573 Net gain on dispositions of discontinued operations 121,922 Total income from discontinued operations $ 124,495

Deferred Leasing Costs and Ac50

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of identified deferred leasing costs and acquisition-related intangible assets	The following table summarizes our deferred leasing costs and acquisition-related intangible assets (acquired value of leasing costs, above-market operating leases, in-place leases and below-market ground lease obligation) and intangible liabilities (acquired value of below-market operating leases and above-market ground lease obligation) as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Deferred Leasing Costs and Acquisition-related Intangible Assets, net: (1) Deferred leasing costs $ 239,958 $ 205,888 Accumulated amortization (89,633 ) (72,745 ) Deferred leasing costs, net 150,325 133,143 Above-market operating leases 10,304 10,989 Accumulated amortization (6,933 ) (6,739 ) Above-market operating leases, net 3,371 4,250 In-place leases 94,813 72,639 Accumulated amortization (40,593 ) (33,810 ) In-place leases, net 54,220 38,829 Below-market ground lease obligation 490 490 Accumulated amortization (38 ) (29 ) Below-market ground lease obligation, net 452 461 Total deferred leasing costs and acquisition-related intangible assets, net $ 208,368 $ 176,683 Acquisition-related Intangible Liabilities, net: (2) Below-market operating leases $ 69,472 $ 53,502 Accumulated amortization (33,689 ) (27,074 ) Below-market operating leases, net 35,783 26,428 Above-market ground lease obligation 6,320 6,320 Accumulated amortization (525 ) (424 ) Above-market ground lease obligation, net 5,795 5,896 Total acquisition-related intangible liabilities, net $ 41,578 $ 32,324 _______________ (1) Excludes deferred leasing costs and acquisition-related intangible assets, net related to properties held for sale as of December 31, 2015 . (2) Included in deferred revenue and acquisition-related intangible liabilities, net in the consolidated balance sheets.
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	The following table sets forth amortization related to deferred leasing costs and acquisition-related intangibles for the years ended December 31, 2016 , 2015 and 2014 , including amounts attributable to discontinued operations for the year ended December 31, 2014. Year Ended December 31, 2016 2015 2014 (in thousands) Deferred leasing costs (1) $ 28,639 $ 27,866 $ 27,555 Above-market operating leases (2) 1,509 2,532 5,303 In-place leases (1) 11,676 14,622 21,628 Below-market ground lease obligation (3) 8 8 8 Below-market operating leases (4) (8,674 ) (10,980 ) (13,238 ) Above-market ground lease obligation (5) (101 ) (101 ) (101 ) Total $ 33,057 $ 33,947 $ 41,155 _______________ (1) The amortization of deferred leasing costs and in-place leases is recorded to depreciation and amortization expense and the amortization of lease incentives is recorded as a reduction to rental income in the consolidated statements of operations for the periods presented. (2) The amortization of above-market operating leases is recorded as a decrease to rental income in the consolidated statements of operations for the periods presented. (3) The amortization of the below-market ground lease obligation is recorded as an increase to ground lease expense in the consolidated statements of operations for the periods presented. (4) The amortization of below-market operating leases is recorded as an increase to rental income in the consolidated statements of operations for the periods presented. (5) The amortization of the above-market ground lease obligation is recorded as a decrease to ground lease expense in the consolidated statements of operations for the periods presented.
Estimated annual amortization related to deferred leasing costs and acquisition-related intangibles	The following table sets forth the estimated annual amortization expense related to deferred leasing costs and acquisition-related intangibles as of December 31, 2016 for future periods: Year Deferred Leasing Costs Above-Market Operating Leases (1) In-Place Leases Below-Market Ground Lease Obligation (2) Below-Market Operating Leases (3) Above-Market Ground Lease Obligation (4) (in thousands) 2017 $ 29,190 $ 1,298 $ 18,366 $ 8 $ (10,633 ) $ (101 ) 2018 25,761 869 13,556 8 (9,116 ) (101 ) 2019 21,397 681 8,856 8 (6,519 ) (101 ) 2020 16,703 53 5,739 8 (3,676 ) (101 ) 2021 12,590 53 2,505 8 (1,031 ) (101 ) Thereafter 44,684 417 5,198 412 (4,808 ) (5,290 ) Total $ 150,325 $ 3,371 $ 54,220 $ 452 $ (35,783 ) $ (5,795 ) _______________ (1) Represents estimated annual amortization related to above-market operating leases. Amounts will be recorded as a decrease to rental income in the consolidated statements of operations. (2) Represents estimated annual amortization related to below-market ground lease obligations. Amounts will be recorded as an increase to ground lease expense in the consolidated statements of operations. (3) Represents estimated annual amortization related to below-market operating leases. Amounts will be recorded as an increase to rental income in the consolidated statements of operations. (4) Represents estimated annual amortization related to above-market ground lease obligations. Amounts will be recorded as a decrease to ground lease expense in the consolidated statements of operations.

Receivables (Tables)

Receivables (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Current Receivables, net	Current receivables, net is primarily comprised of contractual rents and other lease-related obligations due from tenants. The balance consisted of the following as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Current receivables $ 15,172 $ 13,233 Allowance for uncollectible tenant receivables (1,712 ) (2,080 ) Current receivables, net $ 13,460 $ 11,153
Deferred Rent Receivables, net	Deferred rent receivables, net consisted of the following as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Deferred rent receivables $ 220,501 $ 191,586 Allowance for deferred rent receivables (1,524 ) (1,882 ) Deferred rent receivables, net (1) $ 218,977 $ 189,704 __________________ (1) Excludes deferred rent receivables, net related to real estate held for sale as of December 31, 2015.

Prepaid Expenses and Other As52

Prepaid Expenses and Other Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses and other assets, net	Prepaid expenses and other assets, net consisted of the following at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Furniture, fixtures and other long-lived assets, net $ 40,395 $ 11,324 Notes receivable (1) 19,439 3,056 Prepaid expenses 10,774 12,853 Total Prepaid Expenses and Other Assets, Net $ 70,608 $ 27,233 _______________ (1) Approximately $15.1 million of our notes receivables are secured by real estate.

Secured and Unsecured Debt of53

Secured and Unsecured Debt of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Instrument [Line Items]
Exchangeable notes interest expense	The following table summarizes the total interest expense attributable to the 4.25% Exchangeable Notes prior to maturity in November 2014, based on the effective interest rates, before the effect of capitalized interest, for the year ended December 31, 2014 : Year Ended December 31, 2014 Contractual interest payments $ 5,608 Amortization of discount 3,769 Interest expense attributable to the 4.25% Exchangeable Notes $ 9,377
Per share average trading price of the Company's common stock	Period Ended November 15, 2014 (1) Per share average trading price of the Company's common stock $ 60.04 _______________ (1) Represents the maturity date of the 4.25% Exchangeable Notes.
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Schedule of unsecured revolving credit facility	The following table summarizes the balance and terms of our unsecured revolving credit facility as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Outstanding borrowings $ — $ — Remaining borrowing capacity 600,000 600,000 Total borrowing capacity (1) $ 600,000 $ 600,000 Interest rate (2) 1.82 % 1.48 % Facility fee-annual rate (3) 0.200% Maturity date July 2019 _______________ (1) We may elect to borrow, subject to bank approval and obtaining commitments for any additional borrowing capacity, up to an additional $311.0 million under an accordion feature under the terms of the unsecured revolving credit facility and unsecured term loan facility. (2) The interest rate on our unsecured revolving credit facility is based on an annual rate of LIBOR plus 1.050% . (3) Our facility fee is paid on a quarterly basis and is calculated based on the total borrowing capacity. In addition to the facility fee, we incurred debt origination and legal costs. As of December 31, 2016 and 2015 , $3.3 million and $4.6 million of deferred financing costs remained to be amortized through the maturity date of our unsecured revolving credit facility, which are included in prepaid expenses and other assets, net on our consolidated balance sheets.
Schedule of term loan facility	The following table summarizes the balance and terms of our term loan facility, which is included in our unsecured debt, as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Outstanding borrowings (1) $ 150,000 $ 150,000 Interest rate (2) 1.85 % 1.40 % Maturity date July 2019 _______________ (1) As of December 31, 2016 and December 31, 2015 , $0.7 million and $0.9 million of unamortized deferred financing costs, respectively, remained to be amortized through the maturity date of our unsecured term loan facility. (2) Our unsecured term loan facility interest rate was calculated based on an annual rate of LIBOR plus 1.150% .
Stated debt maturities and scheduled amortization payments, excluding debt discounts	The following table summarizes the stated debt maturities and scheduled amortization payments as of December 31, 2016 : Year (in thousands) 2017 $ 7,286 2018 451,669 2019 265,309 2020 255,137 2021 5,342 Thereafter 1,349,023 Total aggregate principal value (1)(2) $ 2,333,766 ________________________ (1) Includes gross principal balance of outstanding debt before the effect of the following at December 31, 2016 : $11.5 million of unamortized deferred financing costs, $6.6 million of unamortized discounts for the unsecured senior notes and $4.4 million of unamortized premiums for the secured debt. (2) Excludes the Series A and B Notes issuable pursuant to the Note Purchase Agreement entered into in September 2016 as no Series A or B Notes were issued and outstanding under these notes as of December 31, 2016 .
Capitalized interest and loan fees	The following table sets forth gross interest expense reported in continuing operations, including debt discount/premium and deferred financing cost amortization, net of capitalized interest, for the years ended December 31, 2016 , 2015 and 2014 . The interest expense capitalized was recorded as a cost of development and redevelopment, and increased the carrying value of undeveloped land and construction in progress. Year Ended December 31, 2016 2015 2014 (in thousands) Gross interest expense $ 105,263 $ 109,647 $ 114,661 Capitalized interest (49,460 ) (51,965 ) (47,090 ) Interest expense $ 55,803 $ 57,682 $ 67,571
Kilroy Realty, L.P. [Member] | Secured debt [Member]
Debt Instrument [Line Items]
Debt balance and significant terms	The following table sets forth the composition of our secured debt as of December 31, 2016 and 2015 : Annual Stated Interest Rate (1) GAAP Effective Rate (1)(2) Maturity Date December 31, Type of Debt 2016 2015 (in thousands) Mortgage note payable (3) 3.57% 3.57% December 2026 $ 170,000 $ — Mortgage note payable (4) 4.27% 4.27% February 2018 125,756 128,315 Mortgage note payable (4) 4.48% 4.48% July 2027 94,754 96,354 Mortgage note payable (4)(5) 6.05% 3.50% June 2019 82,443 85,890 Mortgage note payable (6) 7.15% 7.15% May 2017 1,215 3,987 Mortgage note payable (7) 6.51% 6.51% February 2017 — 65,563 Other (8) Various Various Various — 1,809 Total secured debt $ 474,168 $ 381,918 Unamortized Deferred Financing Costs (1,396 ) (1,083 ) Total secured debt, net $ 472,772 $ 380,835 ______________ (1) All interest rates presented are fixed-rate interest rates. (2) Represents the effective interest rate including the amortization of initial issuance discounts/premiums excluding the amortization of deferred financing costs. (3) This mortgage note payable was entered into in November 2016. (4) The secured debt and the related properties that secure the debt are held in a special purpose entity and the properties are not available to satisfy the debts and other obligations of the Company or the Operating Partnership. (5) As of December 31, 2016 and 2015 , the mortgage loan had unamortized debt premiums of $4.4 million and $6.2 million , respectively. (6) This mortgage note payable was repaid in February 2017 at par. (7) This mortgage note payable was repaid in December 2016 at par. (8) Balance of $1.8 million as of December 31, 2015 included public facility bonds that were assumed by the buyers in connection with sales of land during the year ended December 31, 2016 .
Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Debt Instrument [Line Items]
Debt balance and significant terms	The following table summarizes the balance and significant terms of the registered unsecured senior notes issued by the Operating Partnership as of December 31, 2016 and 2015 : Net Carrying Amount Issuance date Maturity date Stated coupon rate Effective interest rate (1) 2016 2015 (in thousands) 4.375% Unsecured Senior Notes (2) September 2015 October 2025 4.375% 4.440% $ 400,000 $ 400,000 Unamortized discount and deferred financing costs (4,846 ) (5,400 ) Net carrying amount $ 395,154 $ 394,600 4.250% Unsecured Senior Notes (3) July 2014 August 2029 4.250% 4.350% $ 400,000 $ 400,000 Unamortized discount and deferred financing costs (6,696 ) (7,228 ) Net carrying amount $ 393,304 $ 392,772 3.800% Unsecured Senior Notes (4) January 2013 January 2023 3.800% 3.804% $ 300,000 $ 300,000 Unamortized discount and deferred financing costs (1,656 ) (1,931 ) Net carrying amount $ 298,344 $ 298,069 4.800% Unsecured Senior Notes (4)(5) July 2011 July 2018 4.800% 4.827% $ 325,000 $ 325,000 Unamortized discount and deferred financing costs (767 ) (1,251 ) Net carrying amount $ 324,233 $ 323,749 6.625% Unsecured Senior Notes (6) May 2010 June 2020 6.625% 6.743% $ 250,000 $ 250,000 Unamortized discount and deferred financing costs (1,868 ) (2,414 ) Net carrying amount $ 248,132 $ 247,586 Total Unsecured Senior Notes, Net $ 1,659,167 $ 1,656,776 ________________________ (1) Represents the effective interest rate including the amortization of initial issuance discounts, excluding the amortization of deferred financing costs. (2) Interest on these notes is payable semi-annually in arrears on April 1st and October 1st of each year. (3) Interest on these notes is payable semi-annually in arrears on February 15th and August 15th of each year. (4) Interest on these notes is payable semi-annually in arrears on January 15th and July 15th of each year. (5) In October 2015, certain common limited partners in the Operating Partnership that previously contributed their interests in the property at 6255 W. Sunset Blvd., Los Angeles, California to the Operating Partnership entered into an agreement with the Company. Pursuant to this agreement, such common limited partners will reimburse the Company for a portion of any amounts the Company may be required to pay pursuant to its guarantee of the Operating Partnership's 4.800% Senior Notes due 2018 or that the Company may otherwise become required to pay under applicable law with respect to such notes. (6) Interest on these notes is payable semi-annually in arrears on June 1st and December 1st of each year.

Deferred Revenue and Acquisit54

Deferred Revenue and Acquisition Related Liabilities, net (Tables)	12 Months Ended
	Dec. 31, 2016
Deferred Revenue Disclosure [Abstract]
Deferred revenue and acquisition-related liabilities	Deferred revenue and acquisition-related liabilities, net consisted of the following at December 31, 2016 and 2015 : December 31, 2016 2015 (in thousands) Deferred revenue related to tenant-funded tenant improvements (1) $ 99,489 $ 90,825 Other deferred revenue 9,293 5,007 Acquisition-related intangible liabilities, net (2) 41,578 32,324 Total $ 150,360 $ 128,156 ________________________ (1) Excludes deferred revenue related to tenant-funded tenant improvements related to properties held for sale at December 31, 2015 . (2) See Note 2 “Basis of Presentation and Significant Accounting Policies” and Note 5 “Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net” for additional information.
Estimated amortization of deferred revenue related to tenant-funded improvements	The following is the estimated amortization of deferred revenue related to tenant-funded tenant improvements as of December 31, 2016 for the next five years and thereafter: Year Ending (in thousands) 2017 $ 14,453 2018 13,891 2019 12,349 2020 11,767 2021 10,524 Thereafter 36,505 Total $ 99,489

Stockholders' Equity of the C55

Stockholders' Equity of the Company (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Schedule of common stock sales under the at-the-market offering	The following table sets forth information regarding sales of our common stock under our at-the-market offering programs for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in millions, except share data) Shares of common stock sold during the period 451,398 1,866,267 1,599,123 Aggregate gross proceeds $ 32.3 $ 140.1 $ 104.7 Aggregate net proceeds after selling commissions $ 31.9 $ 138.2 $ 103.1
Schedule of accrued dividends and distributions	The following tables summarize accrued dividends and distributions for the noted outstanding shares of common stock, preferred stock, and noncontrolling units as of December 31, 2016 and 2015 : December 31, 2016 2015 (in thousands) Dividends and Distributions payable to: Common stockholders $ 212,074 $ 32,291 Noncontrolling common unitholders of the Operating Partnership 5,418 618 RSU holders (1) 3,158 427 Total accrued dividends and distribution to common stockholders and noncontrolling unitholders 220,650 33,336 Preferred stockholders 1,656 1,656 Total accrued dividends and distributions $ 222,306 $ 34,992 ______________________ (1) The amount includes the value of the dividend equivalents that will be paid with additional RSUs (see Note 15 “Share-Based Compensation” for additional information)
Schedule of outstanding shares of common stock, preferred stock and noncontrolling units	December 31, 2016 2015 Outstanding Shares and Units: Common stock (1) 93,219,439 92,258,690 Noncontrolling common units 2,381,543 1,764,775 RSUs (2) 1,395,189 1,269,809 Series G Preferred stock 4,000,000 4,000,000 Series H Preferred stock 4,000,000 4,000,000 ______________________ (1) The amount includes nonvested shares. (2) The amount includes nonvested RSUs. Does not include the 659,051 and 425,452 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2016 and 2015 , respectively.

Preferred and Common Units of t

Preferred and Common Units of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2016
Class of Stock [Line Items]
Schedule of common stock sales under the at-the-market offering	The following table sets forth information regarding sales of our common stock under our at-the-market offering programs for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in millions, except share data) Shares of common stock sold during the period 451,398 1,866,267 1,599,123 Aggregate gross proceeds $ 32.3 $ 140.1 $ 104.7 Aggregate net proceeds after selling commissions $ 31.9 $ 138.2 $ 103.1
Redeemable noncontrolling interest	The following table sets forth the number of common units held by the Company and the number of common units held by non-affiliated investors and certain of our executive officers and directors in the form of noncontrolling common units as well as the ownership interest held on each respective date: December 31, 2016 December 31, 2015 Company owned common units in the Operating Partnership 93,219,439 92,258,690 Company owned general partnership interest 97.5 % 98.1 % Noncontrolling common units of the Operating Partnership 2,381,543 1,764,775 Ownership interest of noncontrolling interest 2.5 % 1.9 %
Schedule of accrued dividends and distributions	The following tables summarize accrued dividends and distributions for the noted outstanding shares of common stock, preferred stock, and noncontrolling units as of December 31, 2016 and 2015 : December 31, 2016 2015 (in thousands) Dividends and Distributions payable to: Common stockholders $ 212,074 $ 32,291 Noncontrolling common unitholders of the Operating Partnership 5,418 618 RSU holders (1) 3,158 427 Total accrued dividends and distribution to common stockholders and noncontrolling unitholders 220,650 33,336 Preferred stockholders 1,656 1,656 Total accrued dividends and distributions $ 222,306 $ 34,992 ______________________ (1) The amount includes the value of the dividend equivalents that will be paid with additional RSUs (see Note 15 “Share-Based Compensation” for additional information)
Schedule of outstanding shares of common stock, preferred stock and noncontrolling units	December 31, 2016 2015 Outstanding Shares and Units: Common stock (1) 93,219,439 92,258,690 Noncontrolling common units 2,381,543 1,764,775 RSUs (2) 1,395,189 1,269,809 Series G Preferred stock 4,000,000 4,000,000 Series H Preferred stock 4,000,000 4,000,000 ______________________ (1) The amount includes nonvested shares. (2) The amount includes nonvested RSUs. Does not include the 659,051 and 425,452 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2016 and 2015 , respectively.
Kilroy Realty, L.P. [Member]
Class of Stock [Line Items]
Schedule of common stock sales under the at-the-market offering	During the years ended December 31, 2016 , 2015 and 2014 , the Company utilized its at-the-market stock offering programs to issue shares of common stock (see Note 13 “Stockholders’ Equity of the Company” for additional information). The net offering proceeds and property acquired using net offering proceeds were contributed by the Company to the Operating Partnership in exchange for common units for the years ended December 31, 2016 , 2015 and 2014 are as follows: Year Ended December 31, 2016 2015 2014 (in millions, except share and per share data) Shares of common stock contributed by the Company 451,398 1,866,267 1,599,123 Common units exchanged for shares of common stock by the Company 451,398 1,866,267 1,599,123 Aggregate gross proceeds $ 32.3 $ 140.1 $ 104.7 Aggregate net proceeds after selling commissions $ 31.9 $ 138.2 $ 103.1
Schedule of accrued dividends and distributions	The following tables summarize accrued distributions for the noted common and preferred units as of December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 (in thousands) Distributions payable to: General partner $ 212,074 $ 32,291 Common limited partners 5,418 618 RSU holders (1) 3,158 427 Total accrued distributions to common unitholders 220,650 33,336 Preferred unitholders 1,656 1,656 Total accrued distributions $ 222,306 $ 34,992 ______________________ (1) The amount includes the value of the dividend equivalents that will be paid with additional RSUs (see Note 15 “Share-Based Compensation” for additional information).
Schedule of outstanding shares of common stock, preferred stock and noncontrolling units	December 31, 2016 December 31, 2015 Outstanding Units: Common units held by the general partner 93,219,439 92,258,690 Common units held by the limited partners 2,381,543 1,764,775 RSUs (1) 1,395,189 1,269,809 Series G Preferred units 4,000,000 4,000,000 Series H Preferred units 4,000,000 4,000,000 ______________________ (1) Does not include the 659,051 and 425,452 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2016 and 2015 , respectively.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Restricted Stock Units Valuation Assumptions	The total fair value of the Time-Based RSUs is based on the Company's closing share price on the NYSE on the respective fair valuation dates as detailed in the table below: 2016 Time-Based RSU Grant 2015 Time-Based RSU Grant Service vesting period January 28, 2016 - January 5, 2019 January 27, 2015 - January 5, 2018 Fair value on valuation date (in millions) $ 7.1 $ 6.4 Fair value per share $ 56.23 $ 75.34 Date of fair valuation January 28, 2016 January 27, 2015 As a result, the number of RSUs earned as of that date based on the FFO per share performance, excluding the impact of forfeitures, was as follows: 2016 Performance-Based RSU Grant 2015 Performance-Based RSU Grant Service vesting period January 28, 2016 - January 5, 2019 January 27, 2015 - January 5, 2018 Target RSUs granted 168,077 127,657 Estimated RSUs earned based on FFO per share performance condition 241,438 185,510 Date of fair valuation January 28, 2016 January 27, 2015 The following table summarizes the assumptions utilized in the Monte Carlo simulation pricing models: 2016 Award Fair Value Assumptions 2015 Award Fair Value Assumptions Valuation date January 28, 2016 January 27, 2015 Fair value per share on valuation date $57.08 $78.55 Expected share price volatility 26.00% 20.00% Risk-free interest rate 1.13% 0.92% Remaining expected life 2.9 years 2.9 years
Summary of Nonvested Restricted Stock	A summary of our nonvested restricted stock activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested Weighted-Average Outstanding at January 1, 2016 60,797 $ 47.32 Vested (1) (24,262 ) 46.39 Outstanding as of December 31, 2016 36,535 $ 47.93 _______________ (1) The total shares vested includes 12,661 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the restricted shares that have vested. We accept the return of shares at the current quoted closing share price of the Company’s common stock to satisfy tax withholding obligations.
Summary of Nonvested and Vested Restricted Stock Activity	A summary of our nonvested and vested restricted stock activity for years ended December 31, 2016 , 2015 and 2014 is presented below: Shares Granted Shares Vested Years ended December 31, Nonvested Shares Issued Weighted-Average Grant Date Fair Value Per Share Vested Shares Total Fair Value at Vest Date (1) (in thousands) 2016 — $ — (24,262 ) $ 1,527 2015 — — (24,264 ) 1,725 2014 213 51.35 (25,899 ) 1,323 _______________ (1) Total fair value of shares vested was calculated based on the quoted closing share price of the Company’s common stock on the NYSE on the date of vesting.
Schedule of Stock Options Valuation Assumptions	February 2012 Option Grant Fair value of options granted per share $9.20 Expected stock price volatility 33.00% Risk-free interest rate 1.35% Dividend yield 3.80% Expected life of option 6.5 years
Summary of Stock Options Activity	A summary of our stock option activity related to the February 2012 grant from January 1, 2016 through December 31, 2016 is presented below: Number of Options Exercise Price Intrinsic Value (in millions) (1) Outstanding at December 31, 2015 610,000 $ 42.61 $ 12.6 Exercised (286,500 ) 42.61 8.4 Forfeited (9,000 ) 42.61 0.1 Outstanding at December 31, 2016 (2) 314,500 $ 42.61 $ 9.6 Options exercisable at December 31, 2016 (3) 50,500 $ 42.61 $ 1.5 _______________ (1) The intrinsic value of a stock option is the amount by which the fair value of the underlying stock exceeds the exercise price of an option. The fair value of the underlying stock was determined by using the closing share price on the NYSE on the date of exercise, forfeiture or respective period end. (2) As of December 31, 2016 , the average remaining life of stock options outstanding was 5.1 years (3) As of December 31, 2016 , the average remaining life of stock options exercisable was approximately 5.1 years.
Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Restricted Stock Units Award Activity	A summary of our market-measure based RSU activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested RSUs Vested RSUs Total RSUs Amount Weighted-Average (1) Outstanding at January 1, 2016 425,452 $ 67.68 — 425,452 Granted 258,393 57.36 — 258,393 Vested (36,914 ) 43.53 36,914 — Settled (2) (36,914 ) (36,914 ) Issuance of dividend equivalents (3) 12,120 65.50 — 12,120 Outstanding as of December 31, 2016 (4) 659,051 $ 64.95 — 659,051 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014. (2) Represents vested RSUs that were settled in shares of the Company’s common stock. Total shares settled include 19,264 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the RSUs settled. We accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy tax obligations. (3) Represents the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement. (4) Outstanding RSUs as of December 31, 2016 represent the achievement of the maximum performance conditions and assumed target levels for the market conditions. The number of restricted stock units ultimately earned is subject to change based upon actual performance over the three-year vesting period. Dividend equivalents earned will vest along with the underlying award and are also subject to changes based on the number of RSUs ultimately earned for each underlying award. A summary of our market-measure based RSU activity for years ended December 31, 2016 , 2015 and 2014 is presented below: RSUs Granted RSUs Vested Years ended December 31, Non-Vested RSUs Granted Weighted-Average Fair Value Per Share (1) Vested RSUs Total Vest-Date Fair Value (in thousands) 2016 258,393 $ 57.36 (36,914 ) $ 2,788 2015 191,483 79.25 — — 2014 183,365 64.86 (16,338 ) 1,092 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014.
Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Restricted Stock Units Award Activity	A summary of our time-based RSU activity from January 1, 2016 through December 31, 2016 is presented below: Nonvested RSUs Vested RSUs Total RSUs Amount Weighted Average Fair Value (1) Outstanding at January 1, 2016 318,449 $ 58.91 951,360 1,269,809 Granted 173,747 58.29 — 173,747 Vested (130,784 ) 57.91 130,784 — Settled (2) (72,148 ) (72,148 ) Issuance of dividend equivalents (3) 5,027 65.78 23,243 28,270 Canceled (4) (4,489 ) (4,489 ) Outstanding as of December 31, 2016 366,439 $ 59.07 1,028,750 1,395,189 _______________ (1) Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant, which was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014, as an insufficient number of shares were available to settle these RSUs upon initial grant on January 29, 2014. (2) Represents vested RSUs that were settled in shares of the Company’s common stock. Total shares settled include 23,087 shares that were tendered in accordance with the terms of the 2006 Plan to satisfy minimum statutory tax withholding requirements related to the RSUs settled. We accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy tax obligations. (3) Represents the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement. (4) For shares vested but not yet settled, we accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy minimum statutory tax-withholding requirements related to either the settlement or vesting of RSUs in accordance with the terms of the 2006 Plan. A summary of our time-based RSU activity for the years ended December 31, 2016 , 2015 and 2014 is presented below: RSUs Granted RSUs Vested Year ended December 31, Non-Vested RSUs Issued Weighted-Average Grant Date Fair Value Per Share Vested RSUs Total Vest-Date Fair Value (1) (in thousands) 2016 173,747 $ 58.29 (130,784 ) $ 8,438 2015 98,802 74.49 (107,541 ) 7,528 2014 155,016 59.89 (116,447 ) 6,675 _______________ (1) Total fair value of RSUs vested was calculated based on the quoted closing share price of the Company’s common stock on the NYSE on the day of vesting. Excludes the issuance of dividend equivalents earned on the underlying RSUs. The dividend equivalents vest based on terms specified under the related RSU award agreement.

Future Minimum Rent (Tables)

Future Minimum Rent (Tables)	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Future contractual minimum rent under operating lease	Future contractual minimum rent under operating leases as of December 31, 2016 for future periods is summarized as follows: Year Ending (in thousands) 2017 $ 538,269 2018 537,891 2019 493,998 2020 424,791 2021 370,941 Thereafter 1,901,303 Total (1) $ 4,267,193 The minimum commitment under our ground leases as of December 31, 2016 for five years and thereafter is as follows: Year Ending (in thousands) 2017 $ 4,934 2018 4,934 2019 4,934 2020 4,934 2021 4,934 Thereafter 231,402 Total (1)(2)(3)(4)(5) $ 256,072 ________________________ (1) Excludes contingent future rent payments based on gross income or adjusted gross income and reflects the minimum ground lease obligations before the impact of ground lease extension options. (2) One of our ground lease obligations is subject to a fair market value adjustment every five years ; however, the lease includes ground rent subprotection and infrastructure rent credits which currently limit our annual rental obligations to $1.0 million . The contractual obligations for that ground lease included above assumes the lesser of $1.0 million or annual lease rental obligation in effect as of December 31, 2016 . (3) One of our ground lease obligations includes a component which is based on the percentage of gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every five years based on 50% of the average annual percentage rent for the previous five years. (4) One of our ground lease obligations is subject to a fair market value adjustment every five years based on a combination of CPI adjustments and third-party appraisals limited to maximum increases annually. The contractual obligations included above assume the annual lease rental obligation in effect as of December 31, 2016 . (5) One of our ground lease obligations includes a component which is based on the percentage of adjusted gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every 10 years by an amount equal to 60% of the average annual percentage rent for the previous three years.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Schedule of contractual expiration dates for ground leases	The following table summarizes our properties that are held subject to long-term noncancellable ground lease obligations and the respective contractual expiration dates: Property Contractual Expiration Date (1) 601 108th Ave NE, Bellevue, WA November 2093 701, 801 and 837 N. 34th Street, Seattle, WA (2) December 2041 1701 Page Mill Road and 3150 Porter Drive, Palo Alto, CA December 2067 Kilroy Airport Center Phases I, II, and III, Long Beach, CA July 2084 ____________________ (1) Reflects the contractual expiration date prior to the impact of any extension or purchase options held by the Company. (2) The Company has three 10 year and one 45 year extension options for this ground lease, which if exercised would extend the expiration date to December 2116.
Schedule of future minimum rental repayments for ground leases	Future contractual minimum rent under operating leases as of December 31, 2016 for future periods is summarized as follows: Year Ending (in thousands) 2017 $ 538,269 2018 537,891 2019 493,998 2020 424,791 2021 370,941 Thereafter 1,901,303 Total (1) $ 4,267,193 The minimum commitment under our ground leases as of December 31, 2016 for five years and thereafter is as follows: Year Ending (in thousands) 2017 $ 4,934 2018 4,934 2019 4,934 2020 4,934 2021 4,934 Thereafter 231,402 Total (1)(2)(3)(4)(5) $ 256,072 ________________________ (1) Excludes contingent future rent payments based on gross income or adjusted gross income and reflects the minimum ground lease obligations before the impact of ground lease extension options. (2) One of our ground lease obligations is subject to a fair market value adjustment every five years ; however, the lease includes ground rent subprotection and infrastructure rent credits which currently limit our annual rental obligations to $1.0 million . The contractual obligations for that ground lease included above assumes the lesser of $1.0 million or annual lease rental obligation in effect as of December 31, 2016 . (3) One of our ground lease obligations includes a component which is based on the percentage of gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every five years based on 50% of the average annual percentage rent for the previous five years. (4) One of our ground lease obligations is subject to a fair market value adjustment every five years based on a combination of CPI adjustments and third-party appraisals limited to maximum increases annually. The contractual obligations included above assume the annual lease rental obligation in effect as of December 31, 2016 . (5) One of our ground lease obligations includes a component which is based on the percentage of adjusted gross income that exceeds the minimum ground rent. The minimum rent is subject to increases every 10 years by an amount equal to 60% of the average annual percentage rent for the previous three years.

Fair Value Measurements and D60

Fair Value Measurements and Disclosures (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair value of the company's marketable securities	The following table sets forth the fair value of our marketable securities as of December 31, 2016 and 2015 : Fair Value (Level 1) (1) 2016 2015 Description (in thousands) Marketable securities (2) $ 14,773 $ 12,882 _______________ (1) Based on quoted prices in active markets for identical securities. (2) The marketable securities are held in a limited rabbi trust .
Net gain (loss) on marketable securities	The following table sets forth the net gain (loss) on marketable securities recorded during the years ended December 31, 2016 , 2015 and 2014 : December 31, 2016 2015 2014 Description (in thousands) Net gain (loss) on marketable securities $ 1,130 $ (269 ) $ 397
Carrying value and fair value of company's remaining financial assets and liabilities	The following table sets forth the carrying value and the fair value of our other financial instruments as of December 31, 2016 and 2015 : December 31, 2016 2015 Carrying Value Fair Value (1) Carrying Value Fair Value (1) (in thousands) Liabilities Secured debt, net $ 472,772 $ 469,234 $ 380,835 $ 391,611 Unsecured debt, net 1,847,351 1,900,487 1,844,634 1,898,863 _______________ (1) Fair value calculated using Level II inputs, which are based on model-derived valuations in which significant inputs and significant value drivers are observable in active markets.

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Revenue and expense components comprising income from discontinued operations	The following table summarizes the land dispositions completed during the years ended December 31, 2016 , 2015 and 2014 : Properties Submarket Month of Disposition Gross Site Acreage (unaudited) Sales Price (1) (in millions) 2016 Land Dispositions Carlsbad Oaks - Lot 7 (2) Carlsbad January 7.6 $ 4.5 Carlsbad Oaks - Lots 4 & 5 Carlsbad June 11.2 6.0 Carlsbad Oaks - Lot 8 Carlsbad June 13.2 8.9 Total 2016 Land Dispositions (3)(4) 32.0 $ 19.4 2015 Land Disposition 17150 Von Karman (4) Irvine January 8.5 $ 26.0 2014 Land Disposition 10850 Via Frontera (4) Rancho Bernardo April 21.0 $ 33.1 __________________ (1) Represents gross sales price before the impact of commissions and closing costs. (2) This land parcel was classified as held for sale as of December 31, 2015. (3) In connection with these land dispositions, $2.3 million of secured debt was assumed by the buyers. See Note 9 “Secured and Unsecured Debt of the Operating Partnership” for additional information. (4) The 2016 land dispositions resulted in a net loss on sales of $0.3 million and the 2015 and 2014 land dispositions resulted in gain on sales of $17.3 million and $3.5 million , respectively. The following table summarizes the revenue and expense components that comprise income from discontinued operations for the year ended December 31, 2014 : 2014 (in thousands) Revenues: Rental income $ 7,206 Tenant reimbursements 278 Other property income 13 Total revenues 7,497 Expenses: Property expenses 2,171 Real estate taxes 692 Depreciation and amortization 2,061 Total expenses 4,924 Income from discontinued operations before net gain on dispositions of discontinued operations 2,573 Net gain on dispositions of discontinued operations 121,922 Total income from discontinued operations $ 124,495

Net Income Available to Commo62

Net Income Available to Common Stockholders Per Share of the Company (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income available to common stockholders	The following table reconciles the numerator and denominator in computing the Company’s basic and diluted per-share computations for net income available to common stockholders for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 303,798 $ 238,604 $ 59,313 Income from continuing operations attributable to noncontrolling interests (10,010 ) (4,523 ) (966 ) Preferred dividends and distributions (13,250 ) (13,250 ) (13,250 ) Allocation to participating securities (1) (3,839 ) (1,634 ) (1,699 ) Numerator for basic and diluted income from continuing operations available to common stockholders 276,699 219,197 43,398 Income from discontinued operations (2) — — 124,495 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — — (2,623 ) Numerator for basic and diluted net income available to common stockholders $ 276,699 $ 219,197 $ 165,270 Denominator: Basic weighted average vested shares outstanding 92,342,483 89,854,096 83,090,235 Effect of dilutive securities – contingently issuable shares and stock options 680,551 541,679 1,877,485 Diluted weighted average vested shares and common stock equivalents outstanding 93,023,034 90,395,775 84,967,720 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 3.00 $ 2.44 $ 0.52 Income from discontinued operations per share of common stock (2) — — 1.47 Net income available to common stockholders per share $ 3.00 $ 2.44 $ 1.99 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 2.97 $ 2.42 $ 0.51 Income from discontinued operations per share of common stock (2) — — 1.44 Net income available to common stockholders per share $ 2.97 $ 2.42 $ 1.95 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs. (2) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are no longer presented as discontinued operations.

Net Income Available to Commo63

Net Income Available to Common Unitholders Per Unit of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2016
Net Income Available To Common Unitholders [Line Items]
Net income available to common unitholders	The following table reconciles the numerator and denominator in computing the Company’s basic and diluted per-share computations for net income available to common stockholders for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 303,798 $ 238,604 $ 59,313 Income from continuing operations attributable to noncontrolling interests (10,010 ) (4,523 ) (966 ) Preferred dividends and distributions (13,250 ) (13,250 ) (13,250 ) Allocation to participating securities (1) (3,839 ) (1,634 ) (1,699 ) Numerator for basic and diluted income from continuing operations available to common stockholders 276,699 219,197 43,398 Income from discontinued operations (2) — — 124,495 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — — (2,623 ) Numerator for basic and diluted net income available to common stockholders $ 276,699 $ 219,197 $ 165,270 Denominator: Basic weighted average vested shares outstanding 92,342,483 89,854,096 83,090,235 Effect of dilutive securities – contingently issuable shares and stock options 680,551 541,679 1,877,485 Diluted weighted average vested shares and common stock equivalents outstanding 93,023,034 90,395,775 84,967,720 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 3.00 $ 2.44 $ 0.52 Income from discontinued operations per share of common stock (2) — — 1.47 Net income available to common stockholders per share $ 3.00 $ 2.44 $ 1.99 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 2.97 $ 2.42 $ 0.51 Income from discontinued operations per share of common stock (2) — — 1.44 Net income available to common stockholders per share $ 2.97 $ 2.42 $ 1.95 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs. (2) The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are no longer presented as discontinued operations.
Kilroy Realty, L.P. [Member]
Net Income Available To Common Unitholders [Line Items]
Net income available to common unitholders	The following table reconciles the numerator and denominator in computing the Operating Partnership’s basic and diluted per-unit computations for net income available to common unitholders for the years ended December 31, 2016 , 2015 and 2014 : Year Ended December 31, 2016 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 303,798 $ 238,604 $ 59,313 Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries (3,735 ) (467 ) (247 ) Preferred distributions (13,250 ) (13,250 ) (13,250 ) Allocation to participating securities (1) (3,839 ) (1,634 ) (1,699 ) Numerator for basic and diluted income from continuing operations available to common unitholders 282,974 223,253 44,117 Income from discontinued operations (2) — — 124,495 (Income) loss from discontinued operations attributable to noncontrolling interests in consolidated subsidiaries (2) — — (13 ) Numerator for basic and diluted net income available to common unitholders $ 282,974 $ 223,253 $ 168,599 Denominator: Basic weighted average vested units outstanding 94,771,688 91,645,578 84,894,498 Effect of dilutive securities - contingently issuable shares and stock options 680,551 541,679 1,877,485 Diluted weighted average vested units and common unit equivalents outstanding 95,452,239 92,187,257 86,771,983 Basic earnings per unit: Income from continuing operations available to common unitholders per unit $ 2.99 $ 2.44 $ 0.52 Income from discontinued operations per common unit (2) — — 1.47 Net income available to common unitholders per unit $ 2.99 $ 2.44 $ 1.99 Diluted earnings per unit: Income from continuing operations available to common unitholders per unit $ 2.96 $ 2.42 $ 0.51 Income from discontinued operations per common unit (2) — — 1.43 Net income available to common unitholders per unit $ 2.96 $ 2.42 $ 1.94 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs. (2) The Operating Partnership adopted ASU 2014-08 effective January 1, 2015 (see Note 2 “Basis of Presentation and Significant Accounting Policies” for additional information). As a result, properties classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift are no longer presented as discontinued operations.

Supplemental Cash Flow Inform64

Supplemental Cash Flow Information of the Company (Tables)	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Schedule of supplemental cash flows, company	Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common unitholders (Notes 13 and 29) $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 13 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units of the Operating Partnership in connection with an acquisition $ 48,033 $ — $ — Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ — Issuance of shares of common stock in connection with a development property $ — $ — $ 21,631 Exchange of common units of the Operating Partnership into shares of the Company’s common stock $ 8,893 $ 1,223 $ 28 Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 14 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units in connection with a development property acquisition (Note 3) $ 48,033 $ — $ 21,631 Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ —

Supplemental Cash Flow Elements

Supplemental Cash Flow Elements (Tables)	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Schedule of supplemental cash flows, operating unit	Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common unitholders (Notes 13 and 29) $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 13 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units of the Operating Partnership in connection with an acquisition $ 48,033 $ — $ — Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ — Issuance of shares of common stock in connection with a development property $ — $ — $ 21,631 Exchange of common units of the Operating Partnership into shares of the Company’s common stock $ 8,893 $ 1,223 $ 28 Supplemental cash flow information follows (in thousands): Year Ended December 31, 2016 2015 2014 SUPPLEMENTAL CASH FLOWS INFORMATION: Cash paid for interest, net of capitalized interest of $47,675, $50,923, and $44,385 as of December 31, 2016, 2015 and 2014, respectively $ 54,295 $ 54,747 $ 58,944 NON-CASH INVESTING TRANSACTIONS: Accrual for expenditures for operating properties and development and redevelopment properties $ 62,589 $ 109,715 $ 77,091 Tenant improvements funded directly by tenants $ 18,050 $ 13,387 $ 42,906 Assumption of other assets and liabilities in connection with operating and development property acquisitions, net (Note 3) $ 5,863 $ 6,254 $ 14,917 Accrual for receivable related to development properties $ 1,350 $ — $ — Release of holdback funds to third party $ — $ 9,279 $ — NON-CASH FINANCING TRANSACTIONS: Accrual of dividends and distributions payable to common stockholders and common $ 220,650 $ 33,336 $ 31,243 Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders (Notes 14 and 29) $ 1,656 $ 1,656 $ 1,656 Issuance of common units in connection with a development property acquisition (Note 3) $ 48,033 $ — $ 21,631 Secured debt assumed by buyers in connection with land disposition (Note 4) $ 2,322 $ — $ —

Tax Treatment of Distributions

Tax Treatment of Distributions (Tables)	12 Months Ended
	Dec. 31, 2016
Class of Stock [Line Items]
Reconciliation of dividends declared to dividends paid	The following table reconciles the dividends declared per share of common stock to the dividends paid per share of common stock during the years ended December 31, 2016 , 2015 and 2014 as follows: Year Ended December 31, Dividends 2016 2015 2014 Dividends declared per share of common stock $ 3.375 $ 1.400 $ 1.400 Less: Dividends declared in the current year and paid in the following year (1) (2.275 ) (0.350 ) (0.350 ) Add: Dividends declared in the prior year and paid in the current year 0.350 0.350 0.350 Dividends paid per share of common stock $ 1.450 $ 1.400 $ 1.400 _________________ (1) The fourth quarter 2016 dividend of $2.275 per share of common stock consists of a special cash dividend of $1.90 per share of common stock and a regular quarterly cash dividend of $0.375 per share of common stock. The $1.90 per share special distribution is treated as paid in two tax years for income tax purposes: $1.587 is treated as paid on December 31, 2016 and $0.313 is treated as paid on January 13, 2017. The $0.375 per share regular quarterly distribution is considered a 2017 dividend distribution for income tax purposes.
Common stock [Member]
Class of Stock [Line Items]
Reconciliation of dividends declared to dividends paid	The unaudited income tax treatment for the dividends to common stockholders reportable for the years ended December 31, 2016 , 2015 and 2014 as identified in the table above was as follows: Year Ended December 31, Shares of Common Stock 2016 2015 2014 Ordinary income $ 1.500 49.40 % $ 0.992 70.86 % $ 0.998 71.29 % Qualified dividend 0.002 0.06 0.002 0.13 0.002 0.14 Return of capital — — — — 0.398 28.43 Capital gains (1) 1.212 39.89 0.051 3.65 0.002 0.14 Unrecaptured section 1250 gains 0.323 10.65 0.355 25.36 — — $ 3.037 100.00 % $ 1.400 100.00 % $ 1.400 100.00 % _________________ (1) Capital gains are comprised entirely of 20% rate gains.
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Reconciliation of dividends declared to dividends paid	The 6.875% Series G Cumulative Redeemable Preferred Stock was issued in March 2012. The unaudited income tax treatment for the dividends to Series G preferred stockholders reportable for the years ended December 31, 2016 , 2015 , and 2014 was as follows: Year Ended December 31, Preferred Shares 2016 2015 2014 Ordinary income $ 0.848 49.31 % $ 1.218 70.86 % $ 1.711 99.54 % Qualified dividend 0.001 0.06 0.002 0.13 0.003 0.17 Capital gains (1) 0.687 39.97 0.063 3.65 0.005 0.29 Unrecaptured section 1250 gains 0.183 10.66 0.436 25.36 — — $ 1.719 100.00 % $ 1.719 100.00 % $ 1.719 100.00 % __________________ (1) Capital gains are comprised entirely of 20% rate gains.
Series H Preferred Stock [Member]
Class of Stock [Line Items]
Reconciliation of dividends declared to dividends paid	The 6.375% Series H Cumulative Redeemable Preferred Stock was issued in August 2012. The unaudited income tax treatment for the dividends to Series H preferred stockholders reportable for the years ended December 31, 2016 , 2015 , and 2014 was as follows: Year Ended December 31, Preferred Shares 2016 2015 2014 Ordinary income $ 0.786 49.31 % $ 1.129 70.86 % $ 1.587 99.56 % Qualified dividend 0.001 0.06 0.002 0.13 0.003 0.19 Capital gains (1) 0.637 39.97 0.059 3.65 0.004 0.25 Unrecaptured section 1250 gains 0.17 10.66 0.404 25.36 — — $ 1.594 100.00 % $ 1.594 100.00 % $ 1.594 100.00 % __________________ (1) Capital gains are comprised entirely of 20% rate gains.

Quarterly Financial Informati67

Quarterly Financial Information of the Company (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule of summarized quarterly financial data	Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to Kilroy Realty Corporation 174,308 32,847 53,895 32,738 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 170,995 29,535 50,582 29,426 Net income available to common stockholders per share – basic 1.85 0.32 0.54 0.29 Net income available to common stockholders per share – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to Kilroy Realty Corporation 43,187 57,500 104,759 28,635 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 39,874 54,188 101,446 25,323 Net income available to common stockholders per share – basic 0.45 0.61 1.10 0.27 Net income available to common stockholders per share – diluted 0.45 0.61 1.09 0.27 ____________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the Company's repurchase of common stock and its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and its at-the-market stock offering programs that occurred during the year.

Quarterly Financial Informati68

Quarterly Financial Information of the Operating Partnership (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Schedule of summarized quarterly financial data	Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to Kilroy Realty Corporation 174,308 32,847 53,895 32,738 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 170,995 29,535 50,582 29,426 Net income available to common stockholders per share – basic 1.85 0.32 0.54 0.29 Net income available to common stockholders per share – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per share amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to Kilroy Realty Corporation 43,187 57,500 104,759 28,635 Preferred dividends and distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common stockholders 39,874 54,188 101,446 25,323 Net income available to common stockholders per share – basic 0.45 0.61 1.10 0.27 Net income available to common stockholders per share – diluted 0.45 0.61 1.09 0.27 ____________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the Company's repurchase of common stock and its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and its at-the-market stock offering programs that occurred during the year.
Kilroy Realty, L.P. [Member]
Schedule of summarized quarterly financial data	Summarized quarterly financial data for the years ended December 31, 2016 and 2015 was as follows: 2016 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per unit amounts) Revenues $ 145,446 $ 160,133 $ 168,348 $ 168,645 Net income 178,113 33,892 56,375 35,418 Net income attributable to the Operating Partnership 177,833 33,590 55,254 33,386 Preferred distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common unitholders 174,520 30,278 51,941 30,074 Net income available to common unitholders per unit – basic 1.85 0.31 0.54 0.29 Net income available to common unitholders per unit – diluted 1.84 0.31 0.54 0.29 2015 Quarter Ended (1) March 31, June 30, September 30, December 31, (in thousands, except per unit amounts) Revenues $ 146,082 $ 146,227 $ 141,553 $ 147,413 Net income 44,002 58,590 106,704 29,308 Net income attributable to the Operating Partnership 43,927 58,518 106,640 29,052 Preferred distributions (3,313 ) (3,312 ) (3,313 ) (3,312 ) Net income available to common unitholders 40,614 55,206 103,327 25,740 Net income available to common unitholders per unit – basic 0.45 0.61 1.10 0.27 Net income available to common unitholders per unit – diluted 0.45 0.61 1.09 0.27 ___________________ (1) The summation of the quarterly financial data may not equal the annual number reported on the consolidated statements of operations due to rounding. For the year ended December 31, 2016 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to the issuance of common units in connection with an acquisition, the Company’s repurchase of common stock and the its at-the-market stock offering programs that occurred during the year. For the year ended December 31, 2015 , the summation of the quarterly net income available to common stockholders per share does not equal the annual number reported on the consolidated statements of operations due to public offerings of common stock and the Company’s at-the-market stock offering programs that occurred during the year.

Organization and Ownership (Det

Organization and Ownership (Details)	Dec. 31, 2016	Dec. 31, 2016number_of_residential_units	Dec. 31, 2016property_units	Dec. 31, 2016ft²	Dec. 31, 2016project	Dec. 31, 2016tenant	Dec. 31, 2016building	Dec. 31, 2016property	Jan. 31, 2014ft²
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)				14,025,856					79,000
Office properties [Member]
Real Estate Properties [Line Items]
Number of Buildings							108	4
Rentable Square Feet (unaudited)				14,025,856
Number of Tenants | tenant						549
Percentage Occupied (unaudited)	96.00%
Percentage Leased (unaudited)	97.00%
Stabilized residential properties [Member]
Real Estate Properties [Line Items]
Number of Buildings | building							1
Percentage Occupied (unaudited)	46.00%
Percentage Leased (unaudited)	56.50%
Number of units in real estate property | property_units			200
Properties held for sale [Member]
Real Estate Properties [Line Items]
Number of Buildings | property								1
Rentable Square Feet (unaudited)				67,995
Lease up properties [Member]
Real Estate Properties [Line Items]
Number of Buildings | project					1
Rentable Square Feet (unaudited)				377,000
Development properties [Member]
Real Estate Properties [Line Items]
Number of Buildings					3			3
Rentable Square Feet (unaudited)				1,100,000
Number of Residential Units | number_of_residential_units		237
Retail site [Member] | Development properties [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)				96,000

Organization and Ownership (D70

Organization and Ownership (Details Textuals)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016ft²	Dec. 31, 2016project	Dec. 31, 2016building	Dec. 31, 2016a	Dec. 31, 2016property	Dec. 31, 2015	Jan. 31, 2014ft²
Real Estate Properties [Line Items]
Stabilized occupancy	95.00%
Rentable Square Feet (unaudited)		14,025,856						79,000
Percentage of general partnership interest owned by the company in the Operating Partnership	97.50%						98.10%
Ownership interest of noncontrolling interest	2.50%						1.90%
101 First LLC and 303 Second LLC [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership	56.00%
Redwood LLC [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership	93.00%
Kilroy Realty Finance, Inc. [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by wholly-owned subsidiary of the Company	1.00%
Kilroy Realty, L.P. [Member]
Real Estate Properties [Line Items]
Percentage of limited partnership interest owned by Operating Partnership	99.00%
Washington [Member]
Real Estate Properties [Line Items]
Number of Buildings | property						12
Washington - land parcel [Member]
Real Estate Properties [Line Items]
Number of Buildings | building				1
Development properties [Member]
Real Estate Properties [Line Items]
Number of Buildings			3			3
Rentable Square Feet (unaudited)		1,100,000
Development properties [Member] | San Francisco, California [Member]
Real Estate Properties [Line Items]
Number of Buildings | building				2
Rentable Square Feet (unaudited)		640,942
Development properties [Member] | Del Mar, California [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)		73,000
Development Sites [Member]
Real Estate Properties [Line Items]
Number of Buildings | project			7
Office properties [Member]
Real Estate Properties [Line Items]
Number of Buildings				108		4
Rentable Square Feet (unaudited)		14,025,856
Area of land | a					54
Properties and Development Projects [Member]
Real Estate Properties [Line Items]
Property Ownership Percentage	100.00%

Basis of Presentation and Sig71

Basis of Presentation and Significant Accounting Policies (Details)	1 Months Ended		12 Months Ended
	Aug. 31, 2012	Mar. 31, 2012	Dec. 31, 2016USD ($)propertyshares	Dec. 31, 2015USD ($)propertyshares	Dec. 31, 2014USD ($)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Restricted Cash			$ 48,400,000
VIE Asset Amount			654,300,000	$ 203,300,000
VIE, carrying amount, liabilities			166,100,000	28,800,000
Noncontrolling interest in consolidated subsidiary			130,732,000	6,520,000
Depreciation of real estate			171,983,000	159,524,000	$ 153,841,000
Amortization of debt issuance costs			1,400,000
Initial premium on outstanding amount of secured debt			$ 4,400,000
REIT annual taxable income distribution requirement percentage			90.00%
Company annual taxable income distribution			100.00%
Concentration risk, percentage			37.30%
Cash, FDIC insured amount			$ 250,000
Accounting Standards Update 2015-03 and 2015-15 [Member] | Secured debt, net [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Debt issuance costs, net				1,100,000
Accounting Standards Update 2015-03 and 2015-15 [Member] | Unsecured debt, net [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Debt issuance costs, net				12,000,000
Accounting Standards Update 2015-03 and 2015-15 [Member] | Prepaid expenses and other current assets [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Debt issuance costs, line of credit arrangements, net				4,600,000
Real estate investment [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
VIE Asset Amount			588,600,000	187,300,000
Undeveloped land [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Business acquisition, acquisition related costs capitalized			$ 500,000	$ 1,100,000	$ 4,500,000
Properties held for sale [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings | property			1
Torrey Santa Fe Properties [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings | property			4
Torrey Santa Fe Properties [Member] | Properties held for sale [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings | property				4
Minimum [Member] | Building and building improvements [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Property depreciable lives			25 years
Minimum [Member] | Leasehold improvements [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Property depreciable lives			1 year
Maximum [Member] | Building and building improvements [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Property depreciable lives			40 years
Maximum [Member] | Leasehold improvements [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Property depreciable lives			20 years
Lease Agreements [Member] | Minimum [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Finite-lived intangible asset, useful life			1 year
Lease Agreements [Member] | Maximum [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Finite-lived intangible asset, useful life			20 years
Kilroy Realty Finance, Inc. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of general partnership interest owned by wholly-owned subsidiary of the Company			1.00%
Secured debt [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Amortization of debt issuance costs				$ 1,100,000
Unamortized discount (premium), Net				(6,200,000)
Secured debt [Member] | Kilroy Realty, L.P. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Initial premium on outstanding amount of secured debt			$ 4,400,000
Unsecured debt [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Amortization of debt issuance costs			10,100,000	12,000,000
Unamortized discount (premium), Net			(6,600,000)	7,400,000
Line of credit [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Amortization of debt issuance costs			$ 5,700,000	$ 4,300,000
Series G Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares			4,000,000	4,000,000
Preferred stock dividend rate (percentage)			6.875%	6.875%
Series H Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares			4,000,000	4,000,000
Preferred stock dividend rate (percentage)			6.375%	6.375%
Series G Preferred Stock [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares				4,000,000
Preferred stock dividend rate (percentage)		6.875%	6.875%	6.875%
Series G Preferred Stock [Member] | Series G Cumulative Redeemable Preferred Unit [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares			4,000,000
Series H Preferred Stock [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares				4,000,000
Preferred stock dividend rate (percentage)	6.375%		6.375%	6.375%
Series H Preferred Stock [Member] | Series H Cumulative Redeemable Preferred Unit [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Preferred units, issued | shares			4,000,000
Washington [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings | property			12

Acquisitions - 2016 Acquisition

Acquisitions - 2016 Acquisitions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²buildingproperty	Jan. 31, 2014ft²
Business Acquisition [Line Items]
Number of operating properties acquired | property	7
Rentable Square Feet (unaudited) | ft²	14,025,856	79,000
Accounts payable, accrued expenses and other liabilities	$ 1,122
Revenue contributed from 2016 acquired properties	5,200
Net income contributed from 2016 acquired properties	$ 1,700
1290-1300 Terra Bella Avenue, Mountain View, CA [Member]
Business Acquisition [Line Items]
Number of Buildings | building	1
Rentable Square Feet (unaudited) | ft²	114,175
Occupancy as of December 31, 2016 (unaudited)	100.00%
Purchase Price (in millions) (1)	$ 55,400
Accounts payable, accrued expenses and other liabilities	$ 200
8560-8590 West Sunset Blvd., West Hollywood, CA [Member]
Business Acquisition [Line Items]
Number of Buildings | building	4
Rentable Square Feet (unaudited) | ft²	178,699
Occupancy as of December 31, 2016 (unaudited)	87.50%
Purchase Price (in millions) (1)	$ 209,200
Accounts payable, accrued expenses and other liabilities	$ 100
1701 Page Mill Rd. and 3150 Porter Dr., Palo Alto, CA [Member]
Business Acquisition [Line Items]
Number of Buildings | building	2
Rentable Square Feet (unaudited) | ft²	165,585
Occupancy as of December 31, 2016 (unaudited)	100.00%
Purchase Price (in millions) (1)	$ 130,000
Series of individually immaterial business acquisitions [Member]
Business Acquisition [Line Items]
Number of Buildings | building	7
Rentable Square Feet (unaudited) | ft²	458,459
Purchase Price (in millions) (1)	$ 394,600

Acquisitions - Estimated Fair V

Acquisitions - Estimated Fair Values (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Land and improvements	$ 120,110
Buildings and improvements (2)	259,301
Deferred leasing costs and acquisition-related intangible assets (3)	33,529
Total assets acquired	412,940
Accounts payable, accrued expenses and other liabilities	1,122
Deferred revenue and acquisition-related intangible liabilities (4)	18,050
Total liabilities assumed	19,172
Net assets and liabilities acquired	393,768
Below-market leases acquired	$ 18,100
Weighted average amortization period of below-market leases	8 years 4 months 24 days
In-place leases [Member]
Business Acquisition [Line Items]
Deferred leasing costs and acquisition-related intangible assets (3)	$ 27,100
Weighted average amortization period of above-market leases in years	3 years 10 months 24 days
Above market leases [Member]
Business Acquisition [Line Items]
Deferred leasing costs and acquisition-related intangible assets (3)	$ 600
Weighted average amortization period of above-market leases in years	15 years 9 months 18 days
Deferred leasing costs [Member]
Business Acquisition [Line Items]
Deferred leasing costs and acquisition-related intangible assets (3)	$ 5,800
Weighted average amortization period of above-market leases in years	5 years 1 month 6 days

Acquisitions - Development Proj

Acquisitions - Development Project Acquisitions (Details) $ in Thousands	Mar. 11, 2016USD ($)a	Mar. 31, 2016shares	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Total liabilities assumed			$ 19,172
Brannan St Project [Member]
Business Acquisition [Line Items]
Area of land | a	1.75
Payments to acquire businesses	$ 31,000
Business acquisition, equity interest issued or issuable, number of shares | shares		867,701
Business acquisition, equity interest issued or issuable, value assigned	48,000
Business acquisition, transaction costs	2,400
Total liabilities assumed	$ 4,700

Acquisitions - 2015 Acquisition

Acquisitions - 2015 Acquisitions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
333 Dexter [Member]
Business Acquisition [Line Items]
Business acquisition, date of acquisition agreement	Feb. 13, 2015
Payments to acquire land	$ 49.5
Accrued liabilities and acquisition costs	$ 2.4
100 Hooper [Member]
Business Acquisition [Line Items]
Business acquisition, date of acquisition agreement	Jul. 7, 2015
Payments to acquire land	$ 78
Accrued liabilities and acquisition costs	4.1
2015 Total Acquisitions [Member]
Business Acquisition [Line Items]
Payments to acquire land	$ 127.5

Dispositions and Real Estate 76

Dispositions and Real Estate Assets Held for Sale - Operating Property Dispositions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²aproperty	Dec. 31, 2015USD ($)ft²property	Dec. 31, 2014USD ($)ft²property	Jan. 31, 2014ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable Square Feet (unaudited) | ft²	14,025,856			79,000
Gains on sales of depreciable operating properties | $	$ 164,302	$ 109,950	$ 0
Torrey Santa Fe Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property	4
Rentable Square Feet (unaudited) | ft²	465,812
Proceeds from sale of property held-for-sale | $	$ 262,300
4930, 4939 & 4955 Directors Place, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property	2
Rentable Square Feet (unaudited) | ft²	136,908
Proceeds from sale of property held-for-sale | $	$ 49,000
Area of land | a	7
Torrey Santa Fe Properties & 4930, 4939 & 4955 Directors Place, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property	6
Rentable Square Feet (unaudited) | ft²	602,720
Proceeds from sale of property held-for-sale | $	$ 311,300
15050 N.E. 36th St., Redmond, WA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property		1
Rentable Square Feet (unaudited) | ft²		122,103
Proceeds from sale of property held-for-sale | $		$ 51,200
San Diego Properties Tranches 1 & 2, San Diego, CA [Member] [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property		9
Rentable Square Feet (unaudited) | ft²		924,291
Proceeds from sale of property held-for-sale | $		$ 258,000
15050 NE 36th Street, Redmond, WA & San Diego Properties - Tranches 1 and 2 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property		10
Rentable Square Feet (unaudited) | ft²		1,046,394
Proceeds from sale of property held-for-sale | $		$ 309,200
San Diego Properties, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			12
Rentable Square Feet (unaudited) | ft²			1,049,035
Proceeds from sale of property held-for-sale | $			$ 294,700
9785&9791 Towne Centre Drive, San Diego CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			2
Rentable Square Feet (unaudited) | ft²			126,000
Proceeds from sale of property held-for-sale | $			$ 29,500
111 Pacifica [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			1
Rentable Square Feet (unaudited) | ft²			67,496
Proceeds from sale of property held-for-sale | $			$ 15,100
4040 Civic [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			1
Rentable Square Feet (unaudited) | ft²			130,237
Proceeds from sale of property held-for-sale | $			$ 34,900
999 Town &Country [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			1
Rentable Square Feet (unaudited) | ft²			98,551
Proceeds from sale of property held-for-sale | $			$ 25,300
Torrey Santa Fe Properties and 490, 4939, & 4955 Directors Place, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property	6
San Diego Properties, San Diego, CA & 9785 & 9791 Towne Centre Drive, San Diego, CA & 111 Pacifica, Irvine, CA & 4040 Civic Center Drive, San Rafael, CA & 999 Town & Country Road, Orange, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			17
Rentable Square Feet (unaudited) | ft²			1,471,319
Proceeds from sale of property held-for-sale | $			$ 399,500

Dispositions and Real Estate 77

Dispositions and Real Estate Assets Held for Sale - Operating Properties Held for Sale (Details) $ in Millions	1 Months Ended
	Jan. 31, 2017USD ($)	Jan. 31, 2016USD ($)	Dec. 31, 2016ft²buildingproperty	Dec. 31, 2015ft²property	Jan. 31, 2014ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable Square Feet (unaudited)			14,025,856		79,000
Torrey Santa Fe Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			4
Rentable Square Feet (unaudited)			465,812
Properties held for sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property			1
Rentable Square Feet (unaudited)			67,995
Properties held for sale [Member] | Pacific Center Boulevard, Sorrento Mesa, California [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | building			1
Rentable Square Feet (unaudited)			67,995
Properties held for sale [Member] | Torrey Santa Fe Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Buildings | property				4
Rentable Square Feet (unaudited)				465,812
Dispositions sales price | $		$ 262.3
Subsequent event [Member] | Properties held for sale [Member] | Pacific Center Boulevard, Sorrento Mesa, California [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Dispositions sales price | $	$ 12.1

Dispositions and Real Estate 78

Dispositions and Real Estate Assets Held for Sale - Operating Properties Held for Sale - Major Classes of Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	$ 9,417	$ 117,666
Land and land improvements [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	2,693	10,534
Building and building improvements [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	10,500	144,716
Undeveloped land [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	4,824
Total real estate held for sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	13,193	160,074
Accumulated depreciation and amortization [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	3,900	46,191
Total real estate held for sale, net [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	9,293	113,883
Deferred rent receivables, net [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	2,500
Deferred leasing costs [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	1,115
Prepaid expenses and other current assets [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	124	168
Secured debt [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	561
Accounts payable and accrued liabilities [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	56	2,497
Deferred lease revenue [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	2,899
Rents received in advance and tenant security deposits [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	0	1,586
Liabilities and deferred revenue of real estate assets held for sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate held-for-sale	$ 56	$ 7,543

Dispositions and Real Estate 79

Dispositions and Real Estate Assets Held for Sale - Land Dispositions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)a	Dec. 31, 2015USD ($)a	Dec. 31, 2014USD ($)a
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Secured debt assumed by buyers in connection with land disposition	$ 2,322	$ 0	$ 0
Net (loss) gain on sales of land	$ (295)	17,116	$ 3,490
Carlsbad Oaks - Lot 7 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	7.6
Dispositions sales price	$ 4,500
Gain (loss) on sale of properties		$ (200)
Carlsbad Oaks - Lots 4 & 5 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	11.2
Dispositions sales price	$ 6,000
Carlsbad Oaks - Lot 8 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	13.2
Dispositions sales price	$ 8,900
Carlsbad Oaks - Lots 7, 4 & 5, 8 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	32
Dispositions sales price	$ 19,400
Von Karman, Irvine, California [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a		8.5
Dispositions sales price		$ 26,000
Gain (loss) on sale of properties		17,300
10850 Via Frontera San Diego CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a			21
Dispositions sales price			$ 33,100
4930, 4939 & 4955 Directors Place, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	7
Kilroy Realty, L.P. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Secured debt assumed by buyers in connection with land disposition	$ 2,322	0	0
Net (loss) gain on sales of land	$ (295)	$ 17,116	$ 3,490

Dispositions and Real Estate 80

Dispositions and Real Estate Assets Held for Sale - Land Held for Sale (Details) - Carlsbad Oaks - Lot 7 [Member] $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)a	Dec. 31, 2015USD ($)a
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a	7.6
Dispositions sales price	$ 4.5
Gain (loss) on sale of properties		$ (0.2)
Properties held for sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land | a		7.6
Dispositions sales price		$ 4.5

Dispositions and Real Estate 81

Dispositions and Real Estate Assets Held for Sale - Restricted Cash Related to Dispositions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Discontinued Operations and Disposal Groups [Abstract]
Payments of debt extinguishment costs	$ 48.4

Deferred Leasing Costs and Ac82

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, Net
Total deferred leasing costs and acquisition-related intangible assets, net	$ 208,368	$ 176,683
Acquisition-related Intangible Liabilities, Net [Abstract]
Total acquisitions-related intangible liabilities, net	41,578	32,324
Deferred leasing costs [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, Net
Finite-lived intangible assets/liabilities, gross	239,958	205,888
Accumulated amortization	(89,633)	(72,745)
Finite-lived intangible assets	150,325	133,143
Above market leases [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, Net
Finite-lived intangible assets/liabilities, gross	10,304	10,989
Accumulated amortization	(6,933)	(6,739)
Finite-lived intangible assets	3,371	4,250
In-place leases [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, Net
Finite-lived intangible assets/liabilities, gross	94,813	72,639
Accumulated amortization	(40,593)	(33,810)
Finite-lived intangible assets	54,220	38,829
Below-Market Ground Lease Obligation [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, Net
Finite-lived intangible assets/liabilities, gross	490	490
Accumulated amortization	(38)	(29)
Finite-lived intangible assets	452	461
Below Market Operating Lease [Member]
Acquisition-related Intangible Liabilities, Net [Abstract]
Acquisition-related intangible liabilities, gross	69,472	53,502
Accumulated amortization	(33,689)	(27,074)
Acquisition-related intangible liabilities, net	35,783	26,428
Above-Market Ground Lease Obligation [Member]
Acquisition-related Intangible Liabilities, Net [Abstract]
Acquisition-related intangible liabilities, gross	6,320	6,320
Accumulated amortization	(525)	(424)
Acquisition-related intangible liabilities, net	$ 5,795	$ 5,896

Deferred Leasing Costs and Ac83

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	$ 33,057	$ 33,947	$ 41,155
Deferred leasing costs [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	28,639	27,866	27,555
Estimated annual amortization related to acquisition-related intangibles
Finite-lived intangible assets, remainder of 2017	29,190
Finite-lived intangible assets, 2018	25,761
Finite-lived intangible assets, 2019	21,397
Finite-lived intangible assets, 2020	16,703
Finite-lived intangible assets, 2021	12,590
Finite-lived intangible assets, thereafter	44,684
Finite-lived intangible assets	150,325	133,143
Above market leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	1,509	2,532	5,303
Estimated annual amortization related to acquisition-related intangibles
Finite-lived intangible assets, remainder of 2017	1,298
Finite-lived intangible assets, 2018	869
Finite-lived intangible assets, 2019	681
Finite-lived intangible assets, 2020	53
Finite-lived intangible assets, 2021	53
Finite-lived intangible assets, thereafter	417
Finite-lived intangible assets	3,371	4,250
In-place leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	11,676	14,622	21,628
Estimated annual amortization related to acquisition-related intangibles
Finite-lived intangible assets, remainder of 2017	18,366
Finite-lived intangible assets, 2018	13,556
Finite-lived intangible assets, 2019	8,856
Finite-lived intangible assets, 2020	5,739
Finite-lived intangible assets, 2021	2,505
Finite-lived intangible assets, thereafter	5,198
Finite-lived intangible assets	54,220	38,829
Below-Market Ground Lease Obligation [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	8	8	8
Estimated annual amortization related to acquisition-related intangibles
Finite-lived intangible assets, remainder of 2017	8
Finite-lived intangible assets, 2018	8
Finite-lived intangible assets, 2019	8
Finite-lived intangible assets, 2020	8
Finite-lived intangible assets, 2021	8
Finite-lived intangible assets, thereafter	412
Finite-lived intangible assets	452	461
Below Market Operating Lease [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization Of Intangible Liabilities	(8,674)	(10,980)	(13,238)
Estimated annual amortization related to acquisition-related intangibles
Acquisition-related intangible liabilities, remainder of 2017	(10,633)
Acquisition-related intangible liabilities, 2018	(9,116)
Acquisition-related intangible liabilities, 2019	6,519
Acquisition-related intangible liabilities, 2020	3,676
Acquisition-related intangible liabilities, 2021	(1,031)
Acquisition-related intangible liabilities, thereafter	(4,808)
Acquisition-related intangible liabilities	(35,783)	(26,428)
Above-Market Ground Lease Obligation [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization Of Intangible Liabilities	(101)	(101)	$ (101)
Estimated annual amortization related to acquisition-related intangibles
Acquisition-related intangible liabilities, remainder of 2017	(101)
Acquisition-related intangible liabilities, 2018	(101)
Acquisition-related intangible liabilities, 2019	101
Acquisition-related intangible liabilities, 2020	101
Acquisition-related intangible liabilities, 2021	(101)
Acquisition-related intangible liabilities, thereafter	(5,290)
Acquisition-related intangible liabilities	$ (5,795)	$ (5,896)

Receivables (Details)

Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current Receivables, net
Current receivables	$ 15,172	$ 13,233
Allowance for uncollectible tenant receivables	(1,712)	(2,080)
Current receivables, net	13,460	11,153
Deferred Rent Receivables, net
Deferred rent receivables	220,501	191,586
Allowance for deferred rent receivables	(1,524)	(1,882)
Deferred rent receivables, net (1)	$ 218,977	$ 189,704

Prepaid Expenses and Other As85

Prepaid Expenses and Other Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Furniture, fixtures and other long-lived assets, net	$ 40,395	$ 11,324
Notes receivable (1)	19,439	3,056
Prepaid expenses	10,774	12,853
Total Prepaid Expenses and Other Assets, Net	70,608	$ 27,233
Secured debt [Member]
Debt Instrument [Line Items]
Notes receivable (1)	$ 15,100

Secured and Unsecured Debt of86

Secured and Unsecured Debt of the Company (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Outstanding borrowings (1)	$ 1,847,351	$ 1,844,634
Secured debt, net	$ 472,772	380,835
Maximum dividend payment as percentage of funds from operations	95.00%
Line of credit [Member] | $150.0 million term loan facility [Member]
Debt Instrument [Line Items]
Outstanding borrowings (1)	$ 150,000
Unsecured debt [Member]
Debt Instrument [Line Items]
Long-term debt	1,800,000	$ 1,800,000
Unsecured debt [Member] | $39 million unsecured term loan due July 2019 [Member]
Debt Instrument [Line Items]
Outstanding borrowings (1)	$ 39,000
Unsecured senior notes [Member] | 4.80% unsecured senior notes due July 15, 2018 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.80%
Unsecured senior notes [Member] | 6.625% unsecured senior notes due June 1, 2020 [Member]
Debt Instrument [Line Items]
Stated interest rate	6.625%
Unsecured senior notes [Member] | 3.800% unsecured senior notes [Member]
Debt Instrument [Line Items]
Stated interest rate	3.80%
Unsecured senior notes [Member] | 3.48% unsecured senior notes due October 1, 2025 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.375%
Unsecured senior notes [Member] | 4.25% unsecured senior notes [Member]
Debt Instrument [Line Items]
Stated interest rate	4.25%

Secured and Unsecured Debt of87

Secured and Unsecured Debt of the Operating Partnership - Secured Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Secured Debt
Secured debt, net	$ 472,772	$ 380,835
Amortization of debt issuance costs	1,400
Debt premium	4,400
Secured debt [Member]
Secured Debt
Amortization of debt issuance costs		1,100
Kilroy Realty, L.P. [Member]
Secured Debt
Long-term debt, gross	2,333,766
Secured debt, net	472,772	380,835
Kilroy Realty, L.P. [Member] | Secured debt [Member]
Secured Debt
Secured debt, net	474,168	381,918
Long-term debt	472,772	380,835
Debt premium	4,400
Net book value of properties pledged as collateral for secured debt	$ 570,600
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 3.57% Mortgage Payable due December 2026 [Member]
Secured Debt
Stated interest rate	3.57%
Effective interest rate	3.57%
Maturity date	Dec. 1, 2026
Long-term debt, gross	$ 170,000	0
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 4.27% Mortgage Payable due Feb 1, 2018 [Member]
Secured Debt
Stated interest rate	4.27%
Effective interest rate	4.27%
Maturity date	Feb. 1, 2018
Long-term debt, gross	$ 125,756	128,315
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 4.48% Mortgage Payable due July 2027 [Member]
Secured Debt
Stated interest rate	4.48%
Effective interest rate	4.48%
Maturity date	Jul. 1, 2027
Long-term debt, gross	$ 94,754	96,354
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 6.05% Mortgage Payable Due June 1, 2019 [Member]
Secured Debt
Stated interest rate	6.05%
Effective interest rate	3.50%
Maturity date	Jun. 1, 2019
Long-term debt, gross	$ 82,443	85,890
Debt premium	$ 4,400	6,200
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 7.15% Mortgage Payable due May 1, 2017 [Member]
Secured Debt
Stated interest rate	7.15%
Effective interest rate	7.15%
Maturity date	May 1, 2017
Long-term debt, gross	$ 1,215	3,987
Kilroy Realty, L.P. [Member] | Secured debt [Member] | 6.51% Mortgage Payable due February 1, 2017 [Member]
Secured Debt
Stated interest rate	6.51%
Effective interest rate	6.51%
Maturity date	Feb. 1, 2017
Long-term debt, gross	$ 0	65,563
Kilroy Realty, L.P. [Member] | Secured debt [Member] | Other [Member]
Secured Debt
Long-term debt, gross	$ 0	$ 1,809

Secured and Unsecured Debt of88

Secured and Unsecured Debt of the Operating Partnership - Unsecured Senior Notes (Details) - USD ($)	1 Months Ended	12 Months Ended
	Nov. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2015	Nov. 30, 2014
Debt Instrument [Line Items]
Debt instrument, face amount						$ 172,500,000
Repayments of unsecured debt		$ 0	$ 325,000,000	$ 83,000,000
Unsecured Debt [Abstract]
Outstanding borrowings (1)		1,847,351,000	1,844,634,000
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Repayments of unsecured debt		0	325,000,000	$ 83,000,000
Unsecured Debt [Abstract]
Long-term debt, gross		2,333,766,000
Outstanding borrowings (1)		1,847,351,000	1,844,634,000
Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount		(6,600,000)
Unsecured Debt [Abstract]
Outstanding borrowings (1)		$ 1,659,167,000	1,656,776,000
3.475% unsecured senior notes [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 400,000,000
Debt Instrument, Unamortized Discount					$ (2,200,000)
3.48% unsecured senior notes due October 1, 2025 [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Stated interest rate		4.375%
5.00% unsecured senior notes due November 2015 [Member] | Unsecured senior notes [Member]
Debt Instrument [Line Items]
Repayments of unsecured debt	$ 325,000,000
Unsecured Debt [Abstract]
Stated interest rate					5.00%
4.375% unsecured senior notes [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Maturity date		Oct. 1, 2025
Stated interest rate		4.375%
Effective interest rate		4.44%
Long-term debt, gross		$ 400,000,000	400,000,000
Unamortized discount and deferred financing costs		4,846,000	5,400,000
Outstanding borrowings (1)		$ 395,154,000	394,600,000
4.25% unsecured senior notes [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Maturity date		Aug. 15, 2029
Stated interest rate		4.25%
Effective interest rate		4.35%
Long-term debt, gross		$ 400,000,000	400,000,000
Unamortized discount and deferred financing costs		6,696,000	7,228,000
Outstanding borrowings (1)		$ 393,304,000	392,772,000
3.800% unsecured senior notes [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Stated interest rate		3.80%
3.800% unsecured senior notes [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Maturity date		Jan. 15, 2023
Stated interest rate		3.80%
Effective interest rate		3.804%
Long-term debt, gross		$ 300,000,000	300,000,000
Unamortized discount and deferred financing costs		1,656,000	1,931,000
Outstanding borrowings (1)		$ 298,344,000	298,069,000
4.80% unsecured senior notes due July 15, 2018 [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Stated interest rate		4.80%
4.80% unsecured senior notes due July 15, 2018 [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Maturity date		Jul. 15, 2018
Stated interest rate		4.80%
Effective interest rate		4.827%
Long-term debt, gross		$ 325,000,000	325,000,000
Unamortized discount and deferred financing costs		767,000	1,251,000
Outstanding borrowings (1)		$ 324,233,000	323,749,000
6.625% unsecured senior notes due June 1, 2020 [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Stated interest rate		6.625%
6.625% unsecured senior notes due June 1, 2020 [Member] | Kilroy Realty, L.P. [Member] | Unsecured senior notes [Member]
Unsecured Debt [Abstract]
Maturity date		Jun. 1, 2020
Stated interest rate		6.625%
Effective interest rate		6.743%
Long-term debt, gross		$ 250,000,000	250,000,000
Unamortized discount and deferred financing costs		1,868,000	2,414,000
Outstanding borrowings (1)		$ 248,132,000	$ 247,586,000

Secured and Unsecured Debt of89

Secured and Unsecured Debt of the Operating Partnership - Unsecured Senior Notes - Private Placement (Details) - Kilroy Realty, L.P. [Member] - USD ($)	12 Months Ended
	Dec. 31, 2016	Sep. 14, 2016
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,333,766,000
Unsecured debt [Member] | 3.35% Series A Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 175,000,000
Stated interest rate		3.35%
Unsecured debt [Member] | 3.45% Series B Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 75,000,000
Stated interest rate		3.45%
Unsecured debt [Member] | Series A and B Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Operating partnership, payment percent	5.00%
Operating partnership, total payment percentage	100.00%

Secured and Unsecured Debt of90

Secured and Unsecured Debt of the Operating Partnership - Unsecured Revolving Credit Facility and Term Loan Facility (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Terms of Term Loan Facility
Outstanding borrowings (1)	$ 1,847,351,000	$ 1,844,634,000
Kilroy Realty, L.P. [Member]
Terms of the Credit Facility
Unamortized debt issuance expense	11,500,000
Terms of Term Loan Facility
Outstanding borrowings (1)	1,847,351,000	1,844,634,000
Revolving credit facility [Member] | Kilroy Realty, L.P. [Member]
Terms of the Credit Facility
Outstanding borrowings	0	0
Remaining borrowing capacity	600,000,000	600,000,000
Total borrowing capacity (1)	$ 600,000,000	$ 600,000,000
Interest rate (2)	1.82%	1.48%
Facility fee-annual rate (3)	0.20%	0.20%
Maturity date	Jul. 1, 2019	Jul. 1, 2019
Contingent additional borrowings	$ 311,000,000
Unamortized debt issuance expense	$ 3,300,000	$ 4,600,000
Basis spread on LIBOR	1.05%
$150.0 million term loan facility [Member] | Line of credit [Member]
Terms of Term Loan Facility
Outstanding borrowings (1)	$ 150,000,000
$150.0 million term loan facility [Member] | Line of credit [Member] | Kilroy Realty, L.P. [Member]
Terms of the Credit Facility
Unamortized debt issuance expense	700,000	900,000
Terms of Term Loan Facility
Outstanding borrowings (1)	$ 150,000,000	$ 150,000,000
Interest rate (2)	1.85%	1.40%
Maturity date	Jul. 1, 2019
$39 million unsecured term loan due July 2019 [Member] | Line of credit [Member] | Kilroy Realty, L.P. [Member]
Terms of Term Loan Facility
Outstanding borrowings (1)	$ 39,000,000
London Interbank Offered Rate (LIBOR) [Member] | $39 million unsecured term loan due July 2019 [Member] | Line of credit [Member] | Kilroy Realty, L.P. [Member]
Terms of the Credit Facility
Unamortized debt issuance expense	$ 200,000	$ 200,000
Basis spread on LIBOR	1.15%	1.15%

Secured and Unsecured Debt of91

Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) $ in Thousands	Dec. 31, 2016USD ($)
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Debt premium	$ 4,400
Kilroy Realty, L.P. [Member]
Stated debt maturities and scheduled amortization payments, excluding debt discounts
2,017	7,286
2,018	451,669
2,019	265,309
2,020	255,137
2,021	5,342
Thereafter	1,349,023
Total	2,333,766
Unamortized debt issuance expense	(11,500)
Unsecured senior notes [Member] | Kilroy Realty, L.P. [Member]
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Unamortized discount	(6,600)
Secured debt [Member] | Kilroy Realty, L.P. [Member]
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Debt premium	$ 4,400

Secured and Unsecured Debt of92

Secured and Unsecured Debt of the Operating Partnership Secured and Unsecured Debt of the Operating Partnership - Exchangeable Senior Notes (Details) - USD ($) $ / shares in Units, $ in Thousands	Nov. 15, 2014	Dec. 31, 2014	Nov. 30, 2014
Debt Disclosure [Abstract]
Debt instrument, face amount			$ 172,500
Debt Instrument [Line Items]
Average trading price of the Company's stock	$ 60.04
Convertible notes payable [Member]
Debt Instrument [Line Items]
Contractual interest payments		$ 5,608
Amortization of discount		3,769
Interest expense attributable to the 4.25% Exchangeable Notes		$ 9,377
Exchangeable debt [Member]
Debt Instrument [Line Items]
Stated interest rate			4.25%
Debt instrument, convertible, conversion price	$ 35.93

Secured and Unsecured Debt of93

Secured and Unsecured Debt of the Operating Partnership - Capitalized Interest and Loan Fees (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Interest expense	$ 55,803	$ 57,682	$ 67,571
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Gross interest expense	105,263	109,647	114,661
Capitalized interest	49,460	51,965	47,090
Interest expense	$ 55,803	$ 57,682	$ 67,571

Noncontrolling Interests on t94

Noncontrolling Interests on the Company's Consolidated Financial Statements (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2016$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Nov. 30, 2016USD ($)	Aug. 30, 2016USD ($)ft²property	Dec. 31, 2015USD ($)shares
Noncontrolling Interest [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership		97.50%			98.10%
Ownership interest of noncontrolling interest		2.50%			1.90%
Noncontrolling common units | shares		2,381,543			1,764,775
Aggregate value upon redemption of outstanding noncontrolling common units		$ 174,900,000			$ 112,000,000
Noncontrolling interest, increase from sale of parent equity interest		453,449,000
Noncontrolling interest in consolidated subsidiary		130,732,000			6,520,000
Kilroy Realty, L.P. [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest, increase from sale of parent equity interest		453,449,000
100 First LLC & 303 Second LLC [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest in consolidated subsidiary		$ 124,300,000
Redwood LLC [Member]
Noncontrolling Interest [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership		93.00%
Other noncontrolling interests		$ 6,400,000			$ 6,500,000
Capital units [Member] | Kilroy Realty, L.P. [Member]
Noncontrolling Interest [Line Items]
Noncontrolling common units | shares		2,381,543			1,764,775
Brannan St Project [Member]
Noncontrolling Interest [Line Items]
Business acquisition, equity interest issued or issuable, number of shares | shares	867,701
Common stock, par value | $ / shares	$ 0.01	$ 0.01
Consolidated property partnerships [Member]
Noncontrolling Interest [Line Items]
Real estate investments, joint ventures				$ 1,200,000,000
Consolidated property partnerships [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership				44.00%
Ownership interest of noncontrolling interest				44.00%
Number of Buildings | property				2
Other ownership interests, contributed capital				$ 452,900,000
Other ownership interests, mortgage debt				55,300,000
Other ownership interests, contributed capital, working capital contribution			$ 2,900,000	5,000,000
Consolidated property partnerships, tranche one [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Other ownership interests, contributed capital				191,400,000
Other ownership interests, contributed capital, working capital contribution				$ 2,100,000
Additional tax possibly incurred due to transaction		$ 10,900,000
Consolidated property partnerships, tranche one [Member] | 100 First LLC [Member]
Noncontrolling Interest [Line Items]
Area of Real Estate Property | ft²				467,095
Consolidated property partnerships, tranche two [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Other ownership interests, contributed capital			$ 261,500,000
Additional tax possibly incurred due to transaction		18,000,000
Consolidated property partnerships, tranche two [Member] | 303 Second Street [Member]
Noncontrolling Interest [Line Items]
Area of Real Estate Property | ft²				740,047
Noncontrolling Interest In Consolidated Subsidiaries [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest, increase from sale of parent equity interest		124,452,000
Noncontrolling Interest In Consolidated Subsidiaries [Member] | Kilroy Realty, L.P. [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest, increase from sale of parent equity interest		(124,452,000)
Common Stock Additional Paid-in Capital [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest, increase from sale of parent equity interest		$ 328,997,000

Deferred Revenue and Acquisit95

Deferred Revenue and Acquisition Related Liabilities, net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Revenue Arrangement [Line Items]
Acquisition-related intangible liabilities, net	$ 41,578	$ 32,324
Deferred revenue and acquisition-related intangible liabilities, net	150,360	128,156
Tenant funded tenant improvements [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	99,489	90,825
Other deferred revenue [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 9,293	$ 5,007

Deferred Revenue and Acquisit96

Deferred Revenue and Acquisition Related Liabilities, net (Details 2) - Tenant funded tenant improvements [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Revenue Arrangement [Line Items]
Deferred revenues amortized and recognized as rental income	$ 13,200	$ 13,300	$ 11,000
2,017	14,453
2,018	13,891
2,019	12,349
2,020	11,767
2,021	10,524
Thereafter	36,505
Deferred revenue	$ 99,489	$ 90,825

Noncontrolling Interests on t97

Noncontrolling Interests on the Operating Partnership's Consolidated Financial Statements (Details) $ in Thousands	Dec. 31, 2016USD ($)	Nov. 30, 2016USD ($)	Aug. 30, 2016USD ($)property	Dec. 31, 2015USD ($)
Noncontrolling Interest [Line Items]
Company owned general partnership interest	97.50%			98.10%
Noncontrolling interest in consolidated subsidiary	$ 130,732			$ 6,520
Redwood LLC [Member]
Noncontrolling Interest [Line Items]
Company owned general partnership interest	93.00%
Other noncontrolling interests	$ 6,400			$ 6,500
Consolidated property partnerships [Member]
Noncontrolling Interest [Line Items]
Real estate investments, joint ventures			$ 1,200,000
Consolidated property partnerships [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Number of Buildings | property			2
Other ownership interests, contributed capital			$ 452,900
Company owned general partnership interest			44.00%
Other ownership interests, mortgage debt			$ 55,300
Other ownership interests, contributed capital, working capital contribution		$ 2,900	5,000
Consolidated property partnerships, tranche one [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Other ownership interests, contributed capital			191,400
Other ownership interests, contributed capital, working capital contribution			$ 2,100
Consolidated property partnerships, tranche two [Member] | Third party [Member]
Noncontrolling Interest [Line Items]
Other ownership interests, contributed capital		$ 261,500

Stockholders' Equity of the C98

Stockholders' Equity of the Company (Details Textuals) - USD ($)	Dec. 13, 2016	Jul. 31, 2015	Oct. 31, 2014	Aug. 31, 2012	Mar. 31, 2012	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 27, 2017	Feb. 23, 2016	Jul. 01, 2015	Oct. 01, 2014
Class of Stock [Line Items]
At market stock aggregate gross sales price of common stock										$ 300,000,000			$ 249,800,000
Common stock, shares issued													3,733,766
Shares issued, price per share													$ 66.19
Aggregate net proceeds after sales agent compensation		$ 249,600,000
Stock repurchase program, number of shares authorized to be repurchased												4,000,000
Stock repurchase program, remaining number of shares authorized to be repurchased						4,935,826		4,935,826				4,988,025
Stock repurchased during period, shares							52,199
Treasury stock acquired, average cost per share							$ 55.45
Stock repurchased during period, value							$ 2,900,000
Dividends declared per common share	$ 1.90					$ 0.375		$ 3.375	$ 1.4	$ 1.40
Common stock [Member]
Class of Stock [Line Items]
Common stock, shares issued						93,219,439		93,219,439	92,258,690
Dividends declared per common share						$ 2.275		$ 3.375	$ 1.400	$ 1.400
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate (percentage)					6.875%			6.875%	6.875%
Preferred units, issued									4,000,000
Series H Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate (percentage)				6.375%				6.375%	6.375%
Preferred units, issued									4,000,000
Issuance of Equity under ATM Program [Member] | Common stock [Member]
Class of Stock [Line Items]
At market stock aggregate gross sales price of common stock						$ 182,400,000		$ 182,400,000
Common stock, shares issued						2,459,165		2,459,165
At market stock offering program remained available for issuance						$ 117,600,000		$ 117,600,000
Aggregate net proceeds after sales agent compensation								$ 31,900,000	$ 138,200,000	$ 103,100,000
SFFGA [Member]
Class of Stock [Line Items]
Common stock, shares issued														351,476
Purchase price, value of shares issued to acquire land			$ 21,600,000
Series G Cumulative Redeemable Preferred Unit [Member] | Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred units, issued						4,000,000		4,000,000
Series H Cumulative Redeemable Preferred Unit [Member] | Series H Preferred Stock [Member]
Class of Stock [Line Items]
Preferred units, issued						4,000,000		4,000,000
Scenario, forecast [Member] | Series G and H Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, redemption price per share											$ 25
Preferred stock, redemption amount											$ 200,000,000
Preferred stock, redemption amount, potential charge											$ 7,600,000

Stockholders' Equity of the C99

Stockholders' Equity of the Company (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Dividends Payable [Line Items]
Aggregate gross proceeds		$ 31,117	$ 387,398	$ 102,229
Aggregate net proceeds after selling commissions	$ 249,600
Accrued dividend and distributions
Accrued dividends and distributions		222,306	34,992
Accrual of dividends and distributions payable to common stockholders and common unitholders		$ 220,650	$ 33,336	$ 31,243
Summary of shares and units
Common stock		93,219,439	92,258,690
Noncontrolling common units		2,381,543	1,764,775
Common stockholders and noncontrolling unitholders [Member]
Accrued dividend and distributions
Accrued dividends and distributions			$ 33,336
Common stock [Member]
Accrued dividend and distributions
Accrued dividends and distributions		$ 212,074	$ 32,291
Summary of shares and units
Common stock		93,219,439	92,258,690
Capital units [Member]
Accrued dividend and distributions
Accrued dividends and distributions		$ 5,418	$ 618
Preferred Stock [Member]
Accrued dividend and distributions
Accrued dividends and distributions		1,656	$ 1,656
Series G Preferred Stock [Member]
Summary of shares and units
Preferred units, issued			4,000,000
Preferred stock (in shares)			4,000,000
Series H Preferred Stock [Member]
Summary of shares and units
Preferred units, issued			4,000,000
Preferred stock (in shares)			4,000,000
Restricted Stock Units (RSUs) [Member]
Accrued dividend and distributions
Accrued dividends and distributions		$ 3,158	$ 427
Time-Based Restricted Stock Units (RSUs) [Member]
Summary of shares and units
RSUs		1,395,189	1,269,809
Issuance of Equity under ATM Program [Member] | Common stock [Member]
Dividends Payable [Line Items]
Share of common stock sold during the period		451,398	1,866,267	1,599,123
Aggregate gross proceeds		$ 32,300	$ 140,100	$ 104,700
Aggregate net proceeds after selling commissions		31,900	138,200	103,100
Kilroy Realty, L.P. [Member]
Accrued dividend and distributions
Accrued dividends and distributions		$ 222,306	$ 34,992
Accrual of dividends and distributions payable to common stockholders and common unitholders				$ 31,243
Kilroy Realty, L.P. [Member] | Capital units [Member]
Summary of shares and units
Noncontrolling common units		2,381,543	1,764,775
Kilroy Realty, L.P. [Member] | Restricted Stock Units (RSUs) [Member]
Accrued dividend and distributions
Accrued dividends and distributions			$ 427
Kilroy Realty, L.P. [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Summary of shares and units
Number of RSUs outstanding		659,051	425,452

Preferred and Common Units o100

Preferred and Common Units of the Operating Partnership (Details Textuals) - USD ($)	1 Months Ended		3 Months Ended
	Jul. 31, 2015	Oct. 31, 2014	Mar. 31, 2016	Dec. 31, 2016	Jul. 01, 2015	Dec. 31, 2014	Oct. 01, 2014
Class of Stock [Line Items]
Common stock, shares issued					3,733,766
Shares issued, price per share					$ 66.19
At market stock aggregate gross sales price of common stock					$ 249,800,000	$ 300,000,000
Aggregate net proceeds after sales agent compensation	$ 249,600,000
Brannan St Project [Member]
Class of Stock [Line Items]
Business acquisition, equity interest issued or issuable, number of shares			867,701
Share price			$ 55.36
Common stock, par value			$ 0.01	$ 0.01
SFFGA [Member]
Class of Stock [Line Items]
Common stock, shares issued							351,476
Purchase price, value of shares issued to acquire land		$ 21,600,000

Preferred and Common Units o101

Preferred and Common Units of the Operating Partnership (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Aggregate gross proceeds		$ 31,117	$ 387,398	$ 102,229
Aggregate net proceeds after selling commissions	$ 249,600
Summary of units
Company owned general partnership interest		97.50%	98.10%
Noncontrolling common units of the Operating Partnership		2,381,543	1,764,775
Ownership interest of noncontrolling interest		2.50%	1.90%
Accrued distributions
Accrued dividends and distributions		$ 222,306	$ 34,992
Restricted Stock Units (RSUs) [Member]
Accrued distributions
Accrued dividends and distributions		3,158	427
Common stock [Member]
Accrued distributions
Accrued dividends and distributions		212,074	32,291
Capital units [Member]
Accrued distributions
Accrued dividends and distributions		5,418	618
Kilroy Realty, L.P. [Member]
Accrued distributions
Accrued dividends and distributions		$ 222,306	$ 34,992
Kilroy Realty, L.P. [Member] | Restricted Stock Units (RSUs) [Member]
Summary of units
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number		1,395,189	1,269,809
Accrued distributions
Accrued dividends and distributions			$ 427
Kilroy Realty, L.P. [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Summary of units
Number of RSUs outstanding		659,051	425,452
Kilroy Realty, L.P. [Member] | Partners Capital Common Unit [Member]
Class of Stock [Line Items]
Common units exchanged for share of common stock by the Company				1,950,599
Accrued distributions
Accrued dividends and distributions		$ 220,650	$ 33,336
Kilroy Realty, L.P. [Member] | Partners capital general partner [Member]
Accrued distributions
Accrued dividends and distributions		212,074	32,291
Kilroy Realty, L.P. [Member] | Partners capital limited partner [Member]
Accrued distributions
Accrued dividends and distributions		5,418	618
Kilroy Realty, L.P. [Member] | Partners Capital Preferred Units [Member]
Accrued distributions
Accrued dividends and distributions		$ 1,656	$ 1,656
Kilroy Realty, L.P. [Member] | Series G Cumulative Redeemable Preferred Unit [Member]
Summary of units
Preferred units outstanding		4,000,000	4,000,000
Kilroy Realty, L.P. [Member] | Series H Cumulative Redeemable Preferred Unit [Member]
Summary of units
Preferred units outstanding		4,000,000	4,000,000
Kilroy Realty, L.P. [Member] | Capital units [Member]
Summary of units
Company owned common units in the Operating Partnership		93,219,439	92,258,690
Noncontrolling common units of the Operating Partnership		2,381,543	1,764,775
Issuance of Equity under ATM Program [Member] | Partners Capital Common Unit [Member]
Class of Stock [Line Items]
Common units exchanged for share of common stock by the Company		451,398	1,866,267	1,599,123
Issuance of Equity under ATM Program [Member] | Common stock [Member]
Class of Stock [Line Items]
Share of common stock sold during the period		451,398	1,866,267	1,599,123
Aggregate gross proceeds		$ 32,300	$ 140,100	$ 104,700
Aggregate net proceeds after selling commissions		$ 31,900	$ 138,200	$ 103,100

Share-Based Compensation - Stoc

Share-Based Compensation - Stockholder Approved Share-Based Incentive Compensation Plan (Details)	Dec. 31, 2016shares
Shareholder Meeting Date May 21, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares requested	8,320,000
Kilroy Realty 2006 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant	1,286,823

Share-Based Compensation - Exec

Share-Based Compensation - Executive Officer and Key Employee Share-Based Compensation Programs (Details) - Executive officer share-based compensation programs [Member]	12 Months Ended
	Dec. 31, 2016
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award requisite service period	1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award requisite service period	5 years

Share-Based Compensation - 2016

Share-Based Compensation - 2016 and 2015 Share-Based Compensation Grants (Details) - shares	Jan. 28, 2016	Jan. 27, 2015
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	294,821
Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member] | Executive officer share-based compensation programs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period		212,468
Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	168,077	127,657
Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	126,744	84,811

Share-Based Compensation - 2105

Share-Based Compensation - 2016 and 2015 Performance-Based RSU Grants (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 28, 2016	Jan. 27, 2015	Apr. 04, 2013	Feb. 28, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value per share on valuation date						$ 78.55
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Expected share price volatility				33.00%
Risk-free interest rate				1.35%
Remaining expected life				6 years 6 months
2016 Performance Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value RSUs granted	$ 9.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value per share on valuation date					$ 57.08
Expected share price volatility					26.00%
Risk-free interest rate					1.13%
Remaining expected life					2 years 11 months
Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	168,077	127,657
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value per share on valuation date					$ 57.36	$ 79.25	$ 64.86
Expected share price volatility						20.00%
Risk-free interest rate						0.92%
Remaining expected life						2 years 11 months
Market Measure-Based RSU Estimate of Probable [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated RSUs earned based on FFO	241,438	185,510
Chief Executive Officer [Member] | Executive officer share-based compensation programs [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value RSUs granted			$ 10.1

Share-Based Compensation - 2106

Share-Based Compensation - 2016 and 2015 Time-Based RSU Grants (Details) - Time-Based Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, $ in Millions	Jan. 28, 2016	Jan. 27, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price	$ 56.23
Nonvested Restricted Stock Units R S U [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value RSUs granted	$ 7.1	$ 6.4
Chief Executive Officer [Member] | Executive officer share-based compensation programs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price		$ 75.34

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Market-Measure Based RSUs 1 (Details) - $ / shares	Jan. 28, 2016	Jan. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date				$ 78.55
Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU weighted average fair value, beginning balance (per share)			$ 67.68
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	168,077	127,657
Fair value per share on valuation date			57.36	79.25	$ 64.86
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period, weighted average grant date fair value			43.53
Share based compensation arrangements, dividends, weighted average grant date fair value			65.50
RSU weighted average fair value, ending balance (per share)			$ 64.95	$ 67.68
Kilroy Realty, L.P. [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs outstanding, beginning balance			425,452
Number of RSUs outstanding, ending balance			659,051	425,452
Nonvested Restricted Stock Units R S U [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			258,393	191,483	183,365
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			(36,914)
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			12,120
Number of RSUs outstanding, ending balance			659,051
Vested Restricted Stock Units R S U [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested RSUs, beginning balance			0
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			0
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			(36,914)	0	(16,338)
Share-based compensation arrangement by share-based payment award, equity instruments other than options, settled in period			(36,914)
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			0
Vested RSUs, ending balance			0	0
Restricted Stock Units (RSUs) [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total RSUs, beginning balance			425,452
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			258,393
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			0
Share-based compensation arrangement by share-based payment award, equity instruments other than options, settled in period			(36,914)
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			12,120
Total RSUs, ending balance			659,051	425,452
Kilroy Realty 2006 Incentive Award Plan [Member] | Restricted Stock Units (RSUs) [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, settled in period			19,264

Share-Based Compensation - S108

Share-Based Compensation - Summary of Market-Measure Based RSUs 2 (Details) - USD ($)	Jan. 28, 2016	Jan. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date				$ 78.55
Market measure-based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	168,077	127,657
Fair value per share on valuation date			$ 57.36	$ 79.25	$ 64.86
Market measure-based Restricted Stock Units (RSUs) [Member] | Nonvested Restricted Stock Units R S U [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			258,393	191,483	183,365
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			36,914
Market measure-based Restricted Stock Units (RSUs) [Member] | Vested Restricted Stock Units R S U [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			0
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			36,914	0	16,338
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 2,788,000	$ 0	$ 1,092,000

Share-Based Compensation - S109

Share-Based Compensation - Summary of Time-Based RSUs 1 (Details) - $ / shares	Jan. 28, 2016	Jan. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date				$ 78.55
Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (per share)			$ 59.07	$ 58.91
RSUs			1,395,189	1,269,809
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	126,744	84,811
Fair value per share on valuation date			$ 58.29	$ 74.49	$ 59.89
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period, weighted average grant date fair value			57.91
Share based compensation arrangements, dividends, weighted average grant date fair value			$ 65.78
Vested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs			1,028,750	951,360
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			0
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			130,784	107,541	116,447
Stock Issued During Period, Shares, Restricted Stock Award, Gross			72,148
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			23,243
Shares paid for tax withholding for share based compensation			23,087
Restricted Stock Units (RSUs) [Member] | Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number			1,395,189	1,269,809
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			173,747
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			0
Stock Issued During Period, Shares, Restricted Stock Award, Gross			72,148
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			28,270
Shares paid for tax withholding for share based compensation			4,489
Nonvested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			366,439	318,449
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			173,747	98,802	155,016
Share based compensation arrangement by share based payment award equity instruments other than options issuance of dividend equivalents in period			5,027
Shares paid for tax withholding for share based compensation			4,489

Share-Based Compensation - S110

Share-Based Compensation - Summary of Time-Based RSUs 2 (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 28, 2016	Jan. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date				$ 78.55
Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	126,744	84,811
Fair value per share on valuation date			$ 58.29	$ 74.49	$ 59.89
Vested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			0
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period			130,784	107,541	116,447
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 8,438	$ 7,528	$ 6,675
Nonvested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period			173,747	98,802	155,016

Share-Based Compensation - S111

Share-Based Compensation - Summary of Nonvested Restricted Stock 1 (Details) - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (per share)	$ 47.93	$ 47.32
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period		24,264	25,899
Nonvested Restricted Stock Units R S U [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs outstanding	36,535	60,797
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period, weighted average grant date fair value	$ 46.39
Vested Restricted Stock Units R S U [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period	24,262
Shares paid for tax withholding for share based compensation	12,661

Share-Based Compensation - S112

Share-Based Compensation - Summary of Nonvested Restricted Stock 2 (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per share on valuation date		$ 78.55
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period		0	213
Fair value per share on valuation date	$ 0	$ 0	$ 51.35
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period		24,264	25,899
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,527	$ 1,725	$ 1,323
Nonvested Restricted Stock Units R S U [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	0
Vested Restricted Stock Units R S U [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment Award, equity instruments other than options, vested in period	24,262

Share-Based Compensation - S113

Share-Based Compensation - Summary of Stock Options (Textual) (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 22, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vested (in shares)		267,000	298,000	304,000
Stock options vested		$ 2.5	$ 2.7	$ 2.8
Kilroy Realty 2006 Incentive Award Plan [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, withheld in period, intrinsic value		$ 1.8	$ 3.9	$ 1.5
Share-based compensation arrangement by share-based payment award, options, withheld in period		25,680	62,072	23,664
Management [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, grants in period, gross	1,550,000
Share price	$ 42.61
Share-based compensation arrangement by share-based payment award, award vesting period	5 years
Share-based compensation arrangement by share-based payment award, expiration period	10 years

Share-Based Compensation - S114

Share-Based Compensation - Summary of Stock Options 1 (Details) - Employee Stock Option [Member]	1 Months Ended
	Feb. 28, 2012$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 9.20
Expected share price volatility	33.00%
Risk-free interest rate	1.35%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	3.80%
Remaining expected life	6 years 6 months

Share-Based Compensation - S115

Share-Based Compensation - Summary of Stock Options 2 (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, outstanding, weighted average remaining contractual term	5 years 1 month
Share-based compensation arrangement by share-based payment award, options, exercisable, weighted average remaining contractual term	5 years 1 month
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, outstanding, number	314,500	610,000
Share-based compensation arrangement by share-based payment award, options, outstanding, weighted average exercise price	$ 42.61	$ 42.61
Share-based compensation arrangement by share-based payment award, options, outstanding, intrinsic value	$ 9.6	$ 12.6
Exercise of stock options, shares	286,500
Share-based compensation arrangements by share-based payment award, options, exercises in period, weighted average exercise price	$ 42.61
Share-based compensation arrangement by share-based payment award, options, exercises in period, intrinsic value	$ 8.4
Share-based compensation arrangement by share-based payment award, options, forfeitures in period	(9,000)
Share-based compensation arrangement by share-based payment award, options, forfeitures in period, wighted average exercise price	$ 42.61
Share-based compensation arrangement by share-based payment award, options, forfeitures and expirations in period, intrinsic value	$ 0.1
Share-based compensation arrangement by share-based payment award, options, exercisable, number	50,500
Share-based compensation arrangement by share-based payment award, options, exercisable, intrinsic value	$ 1.5

Share-Based Compensation - Shar

Share-Based Compensation - Share-Based Compensation Cost Recorded During the Period (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 26.6	$ 18.9	$ 14.5
Share-based compensation costs	5.6	$ 3.3	$ 2.3
Unrecognized compensation costs	$ 29.6
Cost not yet recognized, period for recognition	1 year 10 months

Employee Benefit Plans Employee

Employee Benefit Plans Employee Benefit Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2007
Compensation and Retirement Disclosure [Abstract]
Eligibility period for 401K savings plan, number of months	3 months
Defined Contribution Plan - maximum participant deferral percent	60.00%
Defined Contribution Plan - employer match per dollar of participant contribution	$ 0.50
Defined Contribution Plan - maximum employer match percentage	10.00%
Defined Contribution Plan - contributions made	$ 1,200,000	$ 1,100,000	$ 1,000,000
Deferred Compensation - maximum participant deferral percent				70.00%
Deferred Compensation - maximum director fees and bonuses that may be deferred (percent)				100.00%
Deferred Compensation - mandatory Company contributions as percentage of gross monthly salary (percent)				10.00%
Deferred Compensation - liability under Plan	$ 14,700,000	$ 12,800,000

Future Minimum Rent (Details)

Future Minimum Rent (Details) $ in Thousands	Dec. 31, 2016USD ($)
Future contractual minimum rent under operating lease
2,017	$ 538,269
2,018	537,891
2,019	493,998
2,020	424,791
2,021	370,941
Thereafter	1,901,303
Total	$ 4,267,193

Commitments and Contingencie119

Commitments and Contingencies (Details) $ in Thousands	Dec. 31, 2016USD ($)
Summary of minimum commitment
2,017	$ 4,934
2,018	4,934
2,019	4,934
2,020	4,934
2,021	4,934
Thereafter	231,402
Total	$ 256,072

Commitments and Contingencie120

Commitments and Contingencies (Details 1) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)Extensions	Dec. 31, 2015USD ($)
Long-term Purchase Commitment [Line Items]
Commitments for contracts and executed leases, operating and redevelopment and development properties	$ 538.6
Period after which ground lease rentals are adjusted based on fair market value and the Consumer Price Index	5 years
Annual ground lease rental obligations limit	$ 1
Duration of ground lease prior to increase five years	5 years
Average annual percentage rent for previous five years (percent)	50.00%
Duration of ground lease prior to increase ten years	10 years
Average annual percentage rent for previous ten years (percent)	60.00%
Accrued environmental remediation liabilities	$ 25.1	$ 20.9
Ten year ground lease extension option [Member]
Long-term Purchase Commitment [Line Items]
Number of extension options | Extensions	3
Ground lease extension option term	10 years
Forty-five year ground lease extension option [Member]
Long-term Purchase Commitment [Line Items]
Number of extension options | Extensions	1
Ground lease extension option term	45 years
Property damage litigation case [Member]
Long-term Purchase Commitment [Line Items]
Proceeds from legal settlements	$ 5

Fair Value Measurements and 121

Fair Value Measurements and Disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair value adjustment of marketable securities and deferred compensation plan liability
Net gain on marketable securities	$ 1,130	$ (269)	$ 397
Fair Value (Level 1) [Member]
Assets and Liabilities Reported at Fair Value
Marketable securities	$ 14,773	$ 12,882

Fair Value Measurements and 122

Fair Value Measurements and Disclosures (Details 1) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Carrying value [Member] | Secured debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value disclosure	$ 472,772	$ 380,835
Carrying value [Member] | Unsecured debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value disclosure	1,847,351	1,844,634
Fair value [Member] | Secured debt [Member] | Fair value (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value disclosure	469,234	391,611
Fair value [Member] | Unsecured debt [Member] | Fair value (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value disclosure	$ 1,900,487	$ 1,898,863

Other Significant Events (Detai

Other Significant Events (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jan. 31, 2014ft²
Other Significant Noncash Transactions [Line Items]
Rentable Square Feet (unaudited) | ft²	14,025,856			79,000
Lease termination fee			$ 5,700
Amortization of intangible assets	$ 33,057	$ 33,947	41,155
Contract termination [Member]
Other Significant Noncash Transactions [Line Items]
Amortization of intangible assets			$ 1,300

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Rental income			$ 7,206
Tenant reimbursements			278
Other property income			13
Total revenues			7,497
Property expenses			2,171
Real estate taxes			692
Depreciation and amortization			2,061
Total expenses			4,924
Income from discontinued operations before net gain on dispositions of discontinued operations	$ 0	$ 0	2,573
Net gain on dispositions of discontinued operations	0	0	121,922
Total income from discontinued operations	$ 0	$ 0	$ 124,495

Net Income Available to Comm125

Net Income Available to Common Stockholders Per Share of the Company (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 2014
Numerator:
Income from continuing operations									$ 303,798	$ 238,604	$ 59,313
Income from continuing operations attributable to noncontrolling interests									(10,010)	(4,523)	(966)
Preferred dividends and distributions	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	(13,250)	(13,250)	(13,250)
Allocation to participating securities (1)									(3,839)	(1,634)	(1,699)
Numerator for basic and diluted income from continuing operations available to common stockholders									276,699	219,197	43,398
Income from discontinued operations (2)									0	0	124,495
Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2)									0	0	(2,623)
Numerator for basic and diluted net income available to common stockholders									$ 276,699	$ 219,197	$ 165,270
Denominator:
Basic weighted average vested shares outstanding									92,342,483	89,854,096	83,090,235
Effect of dilutive securities – contingently issuable shares and stock options									680,551	541,679	1,877,485
Diluted weighted average vested shares and common stock equivalents outstanding									93,023,034	90,395,775	84,967,720
Basic earnings per share:
Income (loss) from continuing operations available to common stockholders per share (dollars per share)									$ 3	$ 2.44	$ 0.52
Income from discontinued operations per share of common stock (dollars per share)									0	0	1.47
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.32	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	3	2.44	1.99
Diluted earnings per share:
Income (loss) from continuing operations available to common stockholders per share (dollars per share)									2.97	2.42	0.51
Income from discontinued operations per share of common stock (dollars per share)									0	0	1.44
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.97	$ 2.42	$ 1.95
Exchangeable debt [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stated interest rate												4.25%

Net Income Available to Comm126

Net Income Available to Common Unitholders Per Unit of the Operating Partnership (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 2014
Numerator:
Income from continuing operations									$ 303,798	$ 238,604	$ 59,313
Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries									(10,010)	(4,523)	(966)
Preferred dividends and distributions	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	(13,250)	(13,250)	(13,250)
Allocation to participating securities (1)									(3,839)	(1,634)	(1,699)
Numerator for basic and diluted income from continuing operations available to common stockholders									276,699	219,197	43,398
Income from discontinued operations (2)									0	0	124,495
(Income) loss from discontinued operations attributable to noncontrolling interests in consolidated subsidiaries (2)									0	0	(2,623)
Numerator for basic and diluted net income available to common stockholders									$ 276,699	$ 219,197	$ 165,270
Denominator:
Basic weighted average vested shares outstanding									92,342,483	89,854,096	83,090,235
Effect of dilutive securities – contingently issuable shares and stock options									680,551	541,679	1,877,485
Diluted weighted average vested shares and common stock equivalents outstanding									93,023,034	90,395,775	84,967,720
Basic earnings per unit:
Income (loss) from continuing operations available to common stockholders per share (dollars per share)									$ 3	$ 2.44	$ 0.52
Income from discontinued operations per common unit (dollars per unit)									0	0	1.47
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.32	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	3	2.44	1.99
Diluted earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit (dollars per unit)									2.97	2.42	0.51
Income from discontinued operations per common unit (dollars per unit)									0	0	1.44
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.97	$ 2.42	$ 1.95
Kilroy Realty, L.P. [Member]
Numerator:
Income from continuing operations									$ 303,798	$ 238,604	$ 59,313
Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries										(467)	(247)
Preferred dividends and distributions	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	$ (3,312)	$ (3,313)	(13,250)	(13,250)	(13,250)
Allocation to participating securities (1)									(3,839)	(1,634)	(1,699)
Numerator for basic and diluted income from continuing operations available to common stockholders									282,974	223,253	44,117
Income from discontinued operations (2)									0	0	124,495
(Income) loss from discontinued operations attributable to noncontrolling interests in consolidated subsidiaries (2)									0	0	(13)
Numerator for basic and diluted net income available to common stockholders									$ 282,974	$ 223,253	$ 168,599
Denominator:
Basic weighted average vested shares outstanding									94,771,688	91,645,578	84,894,498
Effect of dilutive securities – contingently issuable shares and stock options									680,551	541,679	1,877,485
Diluted weighted average vested shares and common stock equivalents outstanding									95,452,239	92,187,257	86,771,983
Basic earnings per unit:
Income (loss) from continuing operations available to common stockholders per share (dollars per share)									$ 2.99	$ 2.44	$ 0.52
Income from discontinued operations per common unit (dollars per unit)									0	0	1.47
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	2.99	2.44	1.99
Diluted earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit (dollars per unit)									2.96	2.42	0.51
Income from discontinued operations per common unit (dollars per unit)									0	0	1.43
Net income available to common stockholders per share (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.96	$ 2.42	$ 1.94
Exchangeable debt [Member]
Diluted earnings per unit:
Debt Instrument, Interest Rate, Stated Percentage												4.25%

Supplemental Cash Flow Infor127

Supplemental Cash Flow Information of the Company (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SUPPLEMENTAL CASH FLOWS INFORMATION:
Interest paid, net	$ 54,295	$ 54,747	$ 58,944
Capitalized interest	44,675	50,923	44,385
NON-CASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	62,589	109,715	77,091
Tenant improvements funded directly by tenants	18,050	13,387	42,906
Assumption of other assets and liabilities in connection with operating and development property acquisitions, net	5,863	6,254	14,917
Accrual for receivable related to development property	1,350	0	0
Release of holdback funds to third party	0	9,279	0
NON-CASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common stockholders and common unitholders	220,650	33,336	31,243
Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders	1,656	1,656	1,656
Issuance of shares/ units of common stock in connection with an acquisition and development property acquisition	48,033	0	21,631
Secured debt assumed by buyers in connection with land disposition	2,322	0	0
Exchange of common units of the Operating Partnership into shares of the Company’s common stock	$ 8,893	$ 1,223	$ 28

Supplemental Cash Flow Infor128

Supplemental Cash Flow Information of the Operating Partnership (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SUPPLEMENTAL CASH FLOWS INFORMATION:
Interest paid, net	$ 54,295	$ 54,747	$ 58,944
Capitalized interest	44,675	50,923	44,385
NON-CASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	62,589	109,715	77,091
Tenant improvements funded directly by tenants	18,050	13,387	42,906
Assumption of other assets and liabilities in connection with operating and development property acquisitions, net	5,863	6,254	14,917
Accrual for receivable related to development property	1,350	0	0
Release of holdback funds to third party	0	9,279	0
NON-CASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common stockholders and common unitholders	220,650	33,336	31,243
Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders	1,656	1,656	1,656
Issuance of shares/ units of common stock in connection with an acquisition and development property acquisition	48,033	0	21,631
Secured debt assumed by buyers in connection with land disposition	2,322	0	0
Kilroy Realty, L.P. [Member]
SUPPLEMENTAL CASH FLOWS INFORMATION:
Interest paid, net	54,295	54,747	58,944
Capitalized interest	47,675	50,923	44,385
NON-CASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties		109,715	77,091
Tenant improvements funded directly by tenants	18,050	13,387	42,906
Assumption of other assets and liabilities in connection with operating and development property acquisitions, net	5,863	6,254	14,917
Release of holdback funds to third party	0	9,279	0
NON-CASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common stockholders and common unitholders			31,243
Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders		1,656	1,656
Secured debt assumed by buyers in connection with land disposition	$ 2,322	$ 0	$ 0

Tax Treatment of Distributio129

Tax Treatment of Distributions (Details) - $ / shares	Jan. 13, 2017	Dec. 13, 2016	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Dividends declared per common share		$ 1.90	$ 0.375	$ 3.375	$ 1.4	$ 1.40
Dividends paid per common share				1.587
Common stock [Member]
Class of Stock [Line Items]
Dividends declared per common share			$ 2.275	3.375	1.400	1.400
Less: Dividends declared in the current year and paid in the following year				(2.275)	(0.350)	(0.350)
Add: Dividends declared in the prior year and paid in the current year				0.350	0.350	0.350
Dividends paid per common share				$ 1.450	$ 1.400	$ 1.400
Scenario, forecast [Member]
Class of Stock [Line Items]
Dividends paid per common share	$ 0.313

Tax Treatment of Distributio130

Tax Treatment of Distributions (Details 1) - $ / shares	1 Months Ended		12 Months Ended
	Aug. 31, 2012	Mar. 31, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 1.587
Capital gains, federal statutory tax rate			20.00%
Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 1.450	$ 1.400	$ 1.400
Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Preferred stock, dividend rate		6.875%	6.875%	6.875%
Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Preferred stock, dividend rate	6.375%		6.375%	6.375%
Tax treatment, Ordinary income [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 1.500	$ 0.992	$ 0.998
Dividends paid per common share, percentage			49.40%	70.86%	71.29%
Tax treatment, Ordinary income [Member] | Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.848	$ 1.218	$ 1.711
Dividend paid per preferred share, percentage			49.31%	70.86%	99.54%
Tax treatment, Ordinary income [Member] | Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.786	$ 1.129	$ 1.587
Dividend paid per preferred share, percentage			49.31%	70.86%	99.56%
Tax treatment, Qualified dividend [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 0.002	$ 0.002	$ 0.002
Dividends paid per common share, percentage			0.06%	0.13%	0.14%
Tax treatment, Qualified dividend [Member] | Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.001	$ 0.002	$ 0.003
Dividend paid per preferred share, percentage			0.06%	0.13%	0.17%
Tax treatment, Qualified dividend [Member] | Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.001	$ 0.002	$ 0.003
Dividend paid per preferred share, percentage			0.06%	0.13%	0.19%
Tax treatment, Return of capital [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 0	$ 0	$ 0.398
Dividends paid per common share, percentage			0.00%	0.00%	28.43%
Tax treatment, Capital gains [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 1.212	$ 0.051	$ 0.002
Dividends paid per common share, percentage			39.89%	3.65%	0.14%
Tax treatment, Capital gains [Member] | Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.687	$ 0.063	$ 0.005
Dividend paid per preferred share, percentage			39.97%	3.65%	0.29%
Tax treatment, Capital gains [Member] | Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.637	$ 0.059	$ 0.004
Dividend paid per preferred share, percentage			39.97%	3.65%	0.25%
Tax treatment, Unrecaptured section 1250 gains [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 0.323	$ 0.355	$ 0
Dividends paid per common share, percentage			10.65%	25.36%	0.00%
Tax treatment, Unrecaptured section 1250 gains [Member] | Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.183	$ 0.436	$ 0
Dividend paid per preferred share, percentage			10.66%	25.36%	0.00%
Tax treatment, Unrecaptured section 1250 gains [Member] | Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 0.170	$ 0.404	$ 0
Dividend paid per preferred share, percentage			10.66%	25.36%	0.00%
Tax treatment [Member] | Common stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per common share			$ 3.037	$ 1.400	$ 1.400
Dividends paid per common share, percentage			100.00%	100.00%	100.00%
Tax treatment [Member] | Series G Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 1.719	$ 1.719	$ 1.719
Dividend paid per preferred share, percentage			100.00%	100.00%	100.00%
Tax treatment [Member] | Series H Preferred Stock [Member]
Income Tax Treatment of Dividends Paid [Line Items]
Dividends paid per preferred share			$ 1.594	$ 1.594	$ 1.594
Dividend paid per preferred share, percentage			100.00%	100.00%	100.00%

Quarterly Financial Informat131

Quarterly Financial Information of the Company (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 168,645	$ 168,348	$ 160,133	$ 145,446	$ 147,413	$ 141,553	$ 146,227	$ 146,082	$ 642,572	$ 581,275	$ 521,725
Net income	35,418	56,375	33,892	178,113	29,308	106,704	58,590	44,002	303,798	238,604	183,808
Net income attributable to Kilroy Realty Corporation	32,738	53,895	32,847	174,308	28,635	104,759	57,500	43,187	293,788	234,081	180,219
Preferred dividends and distributions	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(13,250)	(13,250)	(13,250)
Net income available to common stockholders	$ 29,426	$ 50,582	$ 29,535	$ 170,995	$ 25,323	$ 101,446	$ 54,188	$ 39,874	$ 280,538	$ 220,831	$ 166,969
Net income (loss) available to common stockholders per share—basic (dollars per share)	$ 0.29	$ 0.54	$ 0.32	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	$ 3	$ 2.44	$ 1.99
Net income (loss) available to common stockholders per share—diluted (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.97	$ 2.42	$ 1.95

Quarterly Financial Informat132

Quarterly Financial Information of the Operating Partnership (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues	$ 168,645	$ 168,348	$ 160,133	$ 145,446	$ 147,413	$ 141,553	$ 146,227	$ 146,082	$ 642,572	$ 581,275	$ 521,725
Net income	35,418	56,375	33,892	178,113	29,308	106,704	58,590	44,002	303,798	238,604	183,808
Net income attributable to the Operating Partnership	32,738	53,895	32,847	174,308	28,635	104,759	57,500	43,187	293,788	234,081	180,219
Preferred distributions	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(13,250)	(13,250)	(13,250)
Net income available to common stockholders	$ 29,426	$ 50,582	$ 29,535	$ 170,995	$ 25,323	$ 101,446	$ 54,188	$ 39,874	$ 280,538	$ 220,831	$ 166,969
Net income (loss) available to common stockholders per share—basic (dollars per share)	$ 0.29	$ 0.54	$ 0.32	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	$ 3	$ 2.44	$ 1.99
Net income (loss) available to common stockholders per share—diluted (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.97	$ 2.42	$ 1.95
Kilroy Realty, L.P. [Member]
Revenues	$ 168,645	$ 168,348	$ 160,133	$ 145,446	$ 147,413	$ 141,553	$ 146,227	$ 146,082	$ 642,572	$ 581,275	$ 521,725
Net income	35,418	56,375	33,892	178,113	29,308	106,704	58,590	44,002	303,798	238,604	183,808
Net income attributable to the Operating Partnership	33,386	55,254	33,590	177,833	29,052	106,640	58,518	43,927	300,063	238,137	183,548
Preferred distributions	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(3,312)	(3,313)	(13,250)	(13,250)	(13,250)
Net income available to common stockholders	$ 30,074	$ 51,941	$ 30,278	$ 174,520	$ 25,740	$ 103,327	$ 55,206	$ 40,614	$ 286,813	$ 224,887	$ 170,298
Net income (loss) available to common stockholders per share—basic (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.85	$ 0.27	$ 1.10	$ 0.61	$ 0.45	$ 2.99	$ 2.44	$ 1.99
Net income (loss) available to common stockholders per share—diluted (dollars per share)	$ 0.29	$ 0.54	$ 0.31	$ 1.84	$ 0.27	$ 1.09	$ 0.61	$ 0.45	$ 2.96	$ 2.42	$ 1.94

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 17, 2017	Jan. 13, 2017	Jan. 10, 2017	Dec. 13, 2016	Jan. 28, 2016	Jan. 27, 2015	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jul. 01, 2015
Subsequent Event [Line Items]
Dividends declared per common share				$ 1.90			$ 0.375	$ 3.375	$ 1.4	$ 1.40
Payments of dividends, common stock								$ 137,444	$ 126,839	$ 118,463
Common stock, shares issued											3,733,766
Shares issued, price per share											$ 66.19
Net proceeds from issuance of common stock								$ 31,117	$ 387,398	$ 102,229
Subsequent event [Member]
Subsequent Event [Line Items]
Payments of special cash dividend		$ 184,300
Payments of dividends, common stock		36,400
Common stock, shares issued			4,427,500
Shares issued, price per share			$ 72.75
Net proceeds from issuance of common stock			$ 308,800
Pacific Center Boulevard, Sorrento Mesa, California [Member] | Subsequent event [Member]
Subsequent Event [Line Items]
Proceeds from sale of property held-for-sale		$ 12,100
Market measure-based Restricted Stock Units (RSUs) [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period					168,077	127,657
Market measure-based Restricted Stock Units (RSUs) [Member] | Kilroy Realty 2006 Incentive Award Plan [Member] | Subsequent event [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period	41,119

Schedule II Valuation and Qu134

Schedule II Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for uncollectible tenant receivables
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 2,080	$ 1,999	$ 2,134
Charged to Costs and Expenses	0	303	58
Recoveries (Deductions)	(368)	(222)	(193)
Balance at End of Period (1)	1,712	2,080	1,999
Allowance for deferred rent receivables
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,882	1,989	2,075
Charged to Costs and Expenses	0	242	0
Recoveries (Deductions)	(358)	(349)	(86)
Balance at End of Period (1)	$ 1,524	$ 1,882	$ 1,989

Schedule III - Real Estate a135

Schedule III - Real Estate and Accumulated Depreciation (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jan. 31, 2014ft²	Dec. 31, 2013USD ($)
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 469,766
Real Estate and Accumulated Depreciation, Initial Cost of Land	1,740,313
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,843,637
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,476,804
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,780,084
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	5,280,670
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	7,060,754
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,139,853	$ 994,241	$ 947,664		$ 818,957
Rentable Square Feet (unaudited) | ft²	14,025,856			79,000
Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 469,766
Real Estate and Accumulated Depreciation, Initial Cost of Land	1,069,200
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,843,637
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,134,384
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,108,971
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	4,938,250
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	6,047,221
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,139,853
Rentable Square Feet (unaudited) | ft²	14,025,856
Office Building [Member] | 23925 Park Sorrento, Calabasas, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 1,215
Real Estate and Accumulated Depreciation, Initial Cost of Land	50
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,346
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	495
Real Estate and Accumulated Depreciation, Carrying Amount of Land	50
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	2,841
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	2,891
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,703
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	11,789
Office Building [Member] | 23975 Park Sorrento, Calabasas, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 765
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	17,720
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,579
Real Estate and Accumulated Depreciation, Carrying Amount of Land	765
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	25,299
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	26,064
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 14,562
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	104,797
Office Building [Member] | 24025 Park Sorrento, Calabasas, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 845
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,896
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	8,099
Real Estate and Accumulated Depreciation, Carrying Amount of Land	845
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,995
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	24,840
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 13,559
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	108,670
Office Building [Member] | 2829 Townsgate Rd., Thousand Oaks, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 5,248
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,001
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,461
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,248
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	15,462
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	20,710
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 10,476
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	84,098
Office Building [Member] | 2240 E. Imperial Highway, El Segundo, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,044
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,763
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	29,475
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,048
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	41,234
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	42,282
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 23,131
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	122,870
Office Building [Member] | 2250 E. Imperial Highway, El Segundo, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,579
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	29,062
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	34,978
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,547
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	64,072
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	66,619
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 48,914
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	298,728
Office Building [Member] | 2260 E. Imperial Highway, El Segundo, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,518
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	28,370
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	36,781
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,547
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	65,122
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	67,669
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,560
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	298,728
Office Building [Member] | 909 Sepulveda Boulevard, El Segundo, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances
Real Estate and Accumulated Depreciation, Initial Cost of Land	3,577
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	34,042
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	46,328
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,577
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	80,370
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	83,947
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 32,004
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	244,136
Office Building [Member] | 999 Sepulveda Boulevard, El Segundo, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,407
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	34,326
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	12,392
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,407
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	46,718
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	48,125
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 19,766
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	128,588
Office Building [Member] | 6115 W. Sunset Boulevard, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,313
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	24,922
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,455
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,783
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	26,238
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 901
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	26,105
Office Building [Member] | 6121 W. Sunset Boulevard, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 11,120
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	4,256
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	71,644
Real Estate and Accumulated Depreciation, Carrying Amount of Land	8,703
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	78,317
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	87,020
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,299
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	91,173
Office Building [Member] | 1525 N. Gower Street, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,318
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	8,867
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,318
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,870
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	10,188
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 135
Real estate and accumulated depreciation, life used for depreciation	35 years
Office Building [Member] | 1575 N. Gower Street, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 22,153
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	51
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	97,669
Real Estate and Accumulated Depreciation, Carrying Amount of Land	22,153
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	97,720
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	119,873
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 607
Real estate and accumulated depreciation, life used for depreciation	35 years
Office Building [Member] | 1500 N. El Centro Avenue, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 9,235
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	21
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	36,477
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,235
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	36,498
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	45,733
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 36
Real estate and accumulated depreciation, life used for depreciation	35 years
Office Building [Member] | 1550 N. El Centro Avenue, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 16,970
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	39
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	123,646
Real Estate and Accumulated Depreciation, Carrying Amount of Land	16,970
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	123,685
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	140,655
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,101
Real estate and accumulated depreciation, life used for depreciation	35 years
Office Building [Member] | 6255 Sunset Boulevard, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances
Real Estate and Accumulated Depreciation, Initial Cost of Land	18,111
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	60,320
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	37,000
Real Estate and Accumulated Depreciation, Carrying Amount of Land	18,111
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	97,320
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	115,431
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 17,653
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	323,922
Office Building [Member] | 3750 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 1,941
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,051
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,992
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	12,992
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,628
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	10,457
Office Building [Member] | 3760 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 17,467
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,652
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	29,119
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	29,119
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 23,203
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	165,278
Office Building [Member] | 3780 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 22,319
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	18,983
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	41,302
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	41,302
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 34,274
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	219,745
Office Building [Member] | 3800 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 19,408
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	18,504
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	37,912
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	37,912
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 21,532
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	192,476
Office Building [Member] | 3840 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 13,586
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	9,429
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,015
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	23,015
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 13,922
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	136,026
Office Building [Member] | 3880 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 9,704
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,134
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	20,838
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	20,838
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,416
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	96,035
Office Building [Member] | 3900 Kilroy Airport Way, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	$ 12,615
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,009
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,624
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	23,624
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 14,967
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	129,893
Office Building [Member] | Kilroy Airport Center, Phase IV, Long Beach, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	$ 4,997
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	4,997
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	4,997
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,989
Real estate and accumulated depreciation, life used for depreciation	35 years
Office Building [Member] | 8560 West Sunset Blvd, West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 9,720
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	50,956
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,720
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	50,956
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	60,676
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 170
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	71,875
Office Building [Member] | 8570 West Sunset Blvd, West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 31,693
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	27,974
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	31,693
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	27,974
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	59,667
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 82
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	43,603
Office Building [Member] | 8580 West Sunset Blvd, West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 10,013
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,695
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,013
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	3,695
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	13,708
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 11
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	7,126
Office Building [Member] | 8590 West Sunset Blvd, West Hollywood, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 39,954
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	27,884
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	39,954
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	27,884
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	67,838
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 92
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	56,095
Office Building [Member] | 12100 W. Olympic Boulevard, Los Angeles, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 170,000
Real Estate and Accumulated Depreciation, Initial Cost of Land	352
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	45,611
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	17,548
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,633
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	53,878
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	63,511
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 23,595
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	152,048
Office Building [Member] | 12200 W. Olympic Boulevard, Los Angeles, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,329
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	35,488
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	17,825
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,977
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	53,665
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	57,642
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 33,159
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	150,832
Office Building [Member] | 12233 Olympic Blvd, Los Angeles, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances
Real Estate and Accumulated Depreciation, Initial Cost of Land	22,100
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	53,170
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	3,712
Real Estate and Accumulated Depreciation, Carrying Amount of Land	22,100
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	56,882
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	78,982
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,382
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	151,029
Office Building [Member] | 12312 W. Olympic Boulevard, Los Angeles, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,325
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,202
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,326
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,399
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,454
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	26,853
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,129
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	76,644
Office Building [Member] | 1633 26th Street, Santa Monica, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,080
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,672
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,966
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,040
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	9,678
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	11,718
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,364
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	44,915
Office Building [Member] | 2100 Colorado Avenue, Santa Monica, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 94,754
Real Estate and Accumulated Depreciation, Initial Cost of Land	5,474
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	26,087
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	14,411
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,476
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	40,496
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	45,972
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 20,616
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	102,864
Office Building [Member] | 3130 Wilshire Boulevard, Santa Monica, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 8,921
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,579
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	12,137
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,188
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	18,449
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	27,637
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 12,835
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	88,340
Office Building [Member] | 501 Santa Monica Boulevard, Santa Monica, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,547
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,044
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	10,986
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,551
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,026
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	27,577
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 12,803
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	73,212
Office Building [Member] | 2211 Michelson, Irvine, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 9,319
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	82,836
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	5,310
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,319
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	88,146
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	97,465
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 20,843
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	271,556
Office Building [Member] | 12225 El Camino Real, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,700
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	9,633
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,982
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,673
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,642
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	14,315
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,644
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	58,401
Office Building [Member] | 12235 El Camino Real, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,507
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,543
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	5,584
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,540
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,094
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	15,634
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 8,544
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	53,751
Office Building [Member] | 12340 El Camino Real, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,201
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	13,896
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	8,013
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,201
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	21,909
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	26,110
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,611
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	87,774
Office Building [Member] | 12390 El Camino Real, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,453
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,981
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,377
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,453
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,358
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	16,811
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 8,283
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	72,332
Office Building [Member] | 12348 High Bluff Drive, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,629
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,096
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,829
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,629
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,925
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	9,554
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 5,457
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	38,806
Office Building [Member] | 12400 High Bluff Drive, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 15,167
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	40,497
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	13,109
Real Estate and Accumulated Depreciation, Carrying Amount of Land	15,167
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	53,606
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	68,773
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 23,583
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	209,220
Office Building [Member] | 3579 Valley Centre Drive, Del Mar, California One [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,167
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,897
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,419
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,858
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,625
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	16,483
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 8,426
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	52,418
Office Building [Member] | 3611 Valey Centre Dr., Del Mar, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,184
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	19,352
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	18,501
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,259
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	36,778
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	42,037
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 20,980
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	130,047
Office Building [Member] | 3661 Valley Centre Drive, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,038
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	21,144
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	13,100
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,725
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	33,557
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	38,282
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 17,605
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	128,330
Office Building [Member] | 3721 Valley Centre Drive, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,297
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	18,967
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	14,468
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,254
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	33,478
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	37,732
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 12,666
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	115,193
Office Building [Member] | 3811 Valley Centre Drive, Del Mar, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,452
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	16,152
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	20,092
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,457
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	35,239
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	39,696
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 18,943
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	112,067
Office Building [Member] | 12770 El Camino Real, Del Mar, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 9,360
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	26,880
Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,360
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	26,880
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	36,240
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 0
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	73,032
Office Building [Member] | 12780 El Camino Real, Del Mar, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 18,398
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	54,954
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,626
Real Estate and Accumulated Depreciation, Carrying Amount of Land	18,398
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	56,580
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	74,978
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,289
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	140,591
Office Building [Member] | 12790 El Camino Real, Del Mar, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 10,252
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	21,236
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,342
Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,252
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	22,578
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	32,830
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,816
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	78,836
Office Building [Member] | 13280 Evening Creek Drive, South I-15 Corridor, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,701
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,398
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,589
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,701
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,987
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	16,688
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,945
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	41,196
Office Building [Member] | 13290 Evening Creek Drive, South I-15 Corridor, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 5,229
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,871
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	5,919
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,229
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,790
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	23,019
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,261
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	61,180
Office Building [Member] | 13480 Evening Creek Drive, North I-15 Corridor, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,997
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	48,100
Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,997
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	48,100
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	56,097
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 15,057
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	149,817
Office Building [Member] | 13500 Evening Creek Drive, North I-15 Corridor, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,581
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	35,903
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	8,678
Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,580
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	44,582
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	52,162
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 17,324
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	147,533
Office Building [Member] | 13520 Evening Creek Drive, North I-15 Corridor, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,581
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	35,903
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	11,687
Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,580
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	47,591
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	55,171
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 19,088
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	141,128
Office Building [Member] | 2355 Northside Drive, Mission Valley, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,066
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,332
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,297
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,344
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,351
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	14,695
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,392
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	53,610
Office Building [Member] | 2365 Northside Drive, Mission Valley, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,359
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,257
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,332
Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,015
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,933
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	29,948
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,206
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	96,437
Office Building [Member] | 2375 Northside Drive, Mission Valley, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,947
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,146
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,659
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,213
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,539
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	14,752
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,278
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	51,516
Office Building [Member] | 2385 Northside Drive, Mission Valley, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,752
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	14,513
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	5,299
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,552
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,012
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	22,564
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 5,212
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	89,023
Office Building [Member] | 2305 Historic Decatur Road, San Diego, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 5,240
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	22,220
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,390
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,240
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	29,610
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	34,850
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,143
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	103,900
Office Building [Member] | 10390 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 3,267
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,779
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,501
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,267
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,280
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	16,547
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,222
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	68,400
Office Building [Member] | 10394 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,696
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,134
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	661
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,671
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,820
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	10,491
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,312
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	59,327
Office Building [Member] | 10398 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,947
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,152
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,317
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,222
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,194
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	8,416
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,224
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	43,645
Office Building [Member] | 10421 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,926
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,979
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	22,097
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,926
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	30,076
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	33,002
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 18,321
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	75,899
Office Building [Member] | 10445 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,247
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,945
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,832
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,809
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,215
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	10,024
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,941
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	48,709
Office Building [Member] | 10455 Pacific Center Ct., Sorrento Mesa, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,044
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,701
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	82
Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,780
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,047
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	14,827
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,796
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	88,577
Office Building [Member] | 4690 Executive Dr., University Towne Centre, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 1,623
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,926
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	3,504
Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,623
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,430
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	13,053
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,322
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	47,846
Office Building [Member] | Bohannon Drive 4100, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,835
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,526
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	505
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,860
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,006
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	20,866
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,752
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	47,379
Office Building [Member] | Bohannon Drive 4200, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,798
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,406
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,026
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,662
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,568
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	22,230
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,312
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	45,451
Office Building [Member] | Bohannon Drive 4300, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 6,527
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	20,958
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,749
Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,470
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,764
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	30,234
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 5,031
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	63,079
Office Building [Member] | Bohannon Drive 4400, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,798
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,406
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,469
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,939
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,734
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	22,673
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,501
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	48,146
Office Building [Member] | Bohannon Drive 4500, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 6,527
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	20,957
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,729
Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,470
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	22,743
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	29,213
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,939
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	63,078
Office Building [Member] | Bohannon Drive 4600, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,798
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,406
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,362
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,939
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,627
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	22,566
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,423
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	48,147
Office Building [Member] | Bohannon Drive 4700, Menlo Park, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 6,527
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	20,958
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,397
Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,470
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	22,412
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	28,882
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,825
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	63,078
Office Building [Member] | 1290-1300 Terra Bella Avenue, Mountain View, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 28,730
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	27,555
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	28,730
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	27,555
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	56,285
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 810
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	114,175
Office Building [Member] | Fairchild Drive, 331, Mountain View, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 18,396
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	17,712
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	7,955
Real Estate and Accumulated Depreciation, Carrying Amount of Land	18,396
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	25,667
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	44,063
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,871
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	87,147
Office Building [Member] | 680 E Middlefield Road, Mountain View, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 34,605
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	56,464
Real Estate and Accumulated Depreciation, Carrying Amount of Land	34,605
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	56,464
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	91,069
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,099
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	170,090
Office Building [Member] | 690 E Middlefield Road, Mountain View, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 34,755
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	56,707
Real Estate and Accumulated Depreciation, Carrying Amount of Land	34,755
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	56,707
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	91,462
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,116
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	170,823
Office Building [Member] | 1701 Page Mill Rd, Palo Alto, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	99,522
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	99,522
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	99,522
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 0
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	128,688
Office Building [Member] | 3150 Porter Drive, Palo Alto, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	21,715
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	21,715
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	21,715
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 0
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	36,897
Office Building [Member] | 900 Jefferson Ave., Redwood City, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 16,668
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	109,526
Real Estate and Accumulated Depreciation, Carrying Amount of Land	18,063
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	108,131
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	126,194
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,270
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	228,505
Office Building [Member] | 900 Middlefield Road, Redwood City, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,959
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	49,592
Real Estate and Accumulated Depreciation, Carrying Amount of Land	8,626
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	48,925
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	57,551
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,801
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	118,764
Office Building [Member] | 303 Second Street, San Francisco, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 125,756
Real Estate and Accumulated Depreciation, Initial Cost of Land	63,550
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	154,153
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	46,607
Real Estate and Accumulated Depreciation, Carrying Amount of Land	63,550
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	200,760
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	264,310
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 50,705
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	740,047
Office Building [Member] | 100 First Street, San Francisco, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 49,150
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	131,238
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	32,041
Real Estate and Accumulated Depreciation, Carrying Amount of Land	49,150
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	163,279
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	212,429
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 38,668
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	467,095
Office Building [Member] | 250 Brannan Street, San Francisco, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 7,630
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	22,770
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,416
Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,630
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	27,186
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	34,816
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,256
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	95,008
Office Building [Member] | 201 Third Street, San Francisco, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 19,260
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	84,018
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	43,206
Real Estate and Accumulated Depreciation, Carrying Amount of Land	19,260
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	127,224
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	146,484
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 29,948
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	346,538
Office Building [Member] | 301 Brannan Street, San Francisco, California [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 5,910
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	22,450
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,221
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,910
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	24,671
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	30,581
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 5,115
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	74,430
Office Building [Member] | 360 Third St., San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	88,235
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	112,193
Real Estate and Accumulated Depreciation, Carrying Amount of Land	28,504
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	171,924
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	200,428
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 25,219
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	429,796
Office Building [Member] | 333 Brannan, San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 18,645
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	77,623
Real Estate and Accumulated Depreciation, Carrying Amount of Land	18,645
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	77,623
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	96,268
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,838
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	185,602
Office Building [Member] | 350 Mission Street, San Francisco, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 52,815
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	210,133
Real Estate and Accumulated Depreciation, Carrying Amount of Land	52,815
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	210,133
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	262,948
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,590
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	455,340
Office Building [Member] | 1310 Chesapeake Terrace, Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 16,700
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,020
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	490
Real Estate and Accumulated Depreciation, Carrying Amount of Land	16,700
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,510
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	28,210
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,064
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	76,244
Office Building [Member] | 1315 Chesapeake Terrace, Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 12,260
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,930
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	464
Real Estate and Accumulated Depreciation, Carrying Amount of Land	12,260
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,394
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	20,654
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,002
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	55,635
Office Building [Member] | 1320-1324 Chesapeake Terrace, Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 17,360
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,720
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	544
Real Estate and Accumulated Depreciation, Carrying Amount of Land	17,360
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,264
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	28,624
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,385
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	79,720
Office Building [Member] | 1325-1327 Chesapeake Terrace, Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 12,610
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,160
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	352
Real Estate and Accumulated Depreciation, Carrying Amount of Land	12,610
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,512
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	21,122
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 1,024
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	55,383
Office Building [Member] | 505 Mathilda Ave., Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 37,843
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,163
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	50,554
Real Estate and Accumulated Depreciation, Carrying Amount of Land	37,943
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	51,617
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	89,560
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,442
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	212,322
Office Building [Member] | 555 Mathilda Ave., Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 37,843
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,163
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	50,551
Real Estate and Accumulated Depreciation, Carrying Amount of Land	37,943
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	51,614
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	89,557
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 3,442
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	212,322
Office Building [Member] | 605 Mathilda Ave., Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 29,014
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	891
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	77,359
Real Estate and Accumulated Depreciation, Carrying Amount of Land	29,090
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	78,174
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	107,264
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,479
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	162,785
Office Building [Member] | 599 N. Mathilda Avenue, Sunnyvale, CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 13,538
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,559
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	58
Real Estate and Accumulated Depreciation, Carrying Amount of Land	13,538
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,617
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	26,155
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,374
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	75,810
Office Building [Member] | 601 108th Avenue, Bellevue, Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	214,095
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	32,394
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	246,489
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	246,489
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 51,328
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	488,470
Office Building [Member] | NE 4th Street 10900 Bellevue, Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 25,080
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	150,877
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	21,120
Real Estate and Accumulated Depreciation, Carrying Amount of Land	25,080
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	171,997
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	197,077
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 31,254
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	416,755
Office Building [Member] | 10210 NE Points Dr., Kirkland, Washington [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 4,336
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	24,187
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,933
Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,336
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	27,120
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	31,456
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,151
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	84,641
Office Building [Member] | 10220 NE Points Dr., Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances
Real Estate and Accumulated Depreciation, Initial Cost of Land	2,554
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,080
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,099
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,554
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,179
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	15,733
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 2,956
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	49,851
Office Building [Member] | 10230 NE Points Dr., Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 5,071
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	24,694
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,281
Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,071
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	28,975
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	34,046
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,430
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	98,982
Office Building [Member] | 3933 Lake WA Blvd. NE, Kirkland, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 2,380
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,114
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,965
Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,380
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	20,079
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	22,459
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 4,331
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	46,450
Office Building [Member] | 837 N. 34th St., Lake Union, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	37,404
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	2,547
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	39,951
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	39,951
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 6,914
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	111,580
Office Building [Member] | 701 N. 34th St., Lake Union, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	48,027
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	4,186
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	52,213
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	52,213
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,942
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	138,994
Office Building [Member] | 801 N. 34th St., Lake Union, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	58,537
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	183
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	58,720
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	58,720
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 9,835
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	169,412
Office Building [Member] | 320 Westlake Avenue North, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 78,041
Real Estate and Accumulated Depreciation, Initial Cost of Land	14,710
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	82,018
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,080
Real Estate and Accumulated Depreciation, Carrying Amount of Land	14,710
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	83,098
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	97,808
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 11,082
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	184,643
Office Building [Member] | 321 Terry Avenue North, Lake Union, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 10,430
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	60,003
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	244
Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,430
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	60,247
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	70,677
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 8,463
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	135,755
Office Building [Member] | 401 Terry Avenue North, Lake Union, WA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Initial Cost of Land	$ 22,500
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	77,046
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	22,500
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	77,046
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	99,546
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 7,556
Real estate and accumulated depreciation, life used for depreciation	35 years
Rentable Square Feet (unaudited) | ft²	140,605
Undeveloped Land and CIP Properties [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Land	671,113
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	342,420
Real Estate and Accumulated Depreciation, Carrying Amount of Land	671,113
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	342,420
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	1,013,533
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 0
Rentable Square Feet (unaudited) | ft²	0

Schedule III - Real Estate a136

Schedule III - Real Estate and Accumulated Depreciation (Details 2) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Total real estate held for investment, beginning of year		$ 6,328,146	$ 6,057,932	$ 5,264,947
Acquisitions		460,957	139,123	340,296
Improvements, etc.		386,836	536,411	588,166
Total additions during period		847,793	675,534	928,462
Cost of real estate sold		(68,200)	(231,984)	(113,416)
Properties held for sale		(13,193)	(160,074)	(14,700)
Other	[1]	(33,792)	(13,262)	(7,361)
Total deductions during period		(115,185)	(405,320)	(135,477)
Total real estate held for investment, end of year		$ 7,060,754	$ 6,328,146	$ 6,057,932
[1]	{F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOjVlYWUxOGQ2MWUyMTQ1ZTQ4MTc2MTE2MzQ3ODAxZmRifFRleHRTZWxlY3Rpb246MDNGOTM1MjA3M0MwQzkxRjY5NDNBRUZEMTcwRkFCOTAM}

Schedule III - Real Estate a137

Schedule III - Real Estate and Accumulated Depreciation (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Accumulated depreciation, beginning of year	$ 994,241	$ 947,664	$ 818,957
Depreciation of real estate	171,983	159,524	153,841
SEC Schedule III, Real Estate Accumulated Depreciation, Period Increase	171,983	159,524	153,841
Write-offs due to sale	(22,471)	(66,603)	(18,111)
Properties held for sale	(3,900)	(46,191)	(7,007)
Other additions	0
Other deductions		(153)	(16)
Total deductions during period	(26,371)	(112,947)	(25,134)
Accumulated depreciation, end of year	$ 1,139,853	$ 994,241	$ 947,664

Schedule III - Real Estate a138

Schedule III - Real Estate and Accumulated Depreciation (Details) (Textuals) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²	Jan. 31, 2014ft²
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 469,766
Rentable Square Feet (unaudited) | ft²	14,025,856	79,000
Debt premium	$ 4,400
Amortization of debt issuance costs	1,400
Aggregate cost of property for federal income tax purposes	$ 5,900,000
Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Tenant Improvements [Member] | Minimum [Member]
Real Estate and Accumulated Depreciation [Line Items]
Property depreciable lives	1 year
Tenant Improvements [Member] | Maximum [Member]
Real Estate and Accumulated Depreciation [Line Items]
Property depreciable lives	20 years
Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, amount of encumbrances	$ 469,766
Rentable Square Feet (unaudited) | ft²	14,025,856
23925 Park Sorrento, Calabasas, California [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances	$ 1,215
Rentable Square Feet (unaudited) | ft²	11,789
12100 W. Olympic Boulevard, Los Angeles, California [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances	$ 170,000
Rentable Square Feet (unaudited) | ft²	152,048
909 Sepulveda Boulevard, El Segundo, California [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances
Rentable Square Feet (unaudited) | ft²	244,136
2100 Colorado Avenue, Santa Monica, California [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances	$ 94,754
Rentable Square Feet (unaudited) | ft²	102,864
303 Second Street, San Francisco, California [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances	$ 125,756
Rentable Square Feet (unaudited) | ft²	740,047
320 Westlake Avenue North, WA [Member] | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation, life used for depreciation	35 years
Real estate and accumulated depreciation, amount of encumbrances	$ 78,041
Rentable Square Feet (unaudited) | ft²	184,643
Lease up properties [Member]
Real Estate and Accumulated Depreciation [Line Items]
Rentable Square Feet (unaudited) | ft²	377,000
Variable Interest Entity
Real Estate and Accumulated Depreciation [Line Items]
Gross costs attributable to properties held	$ 200,000