Kilroy Realty (KRC) 10-Q 29 Oct 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 23, 2015
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-Q
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		92,220,367
Kilroy Realty, L.P. [Member]
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-Q
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
REAL ESTATE ASSETS:
Land and improvements		$ 850,280	$ 877,633
Buildings and improvements		4,028,044	4,059,639
Undeveloped land and construction in progress (Note 2)		1,475,718	1,120,660
Total real estate assets held for investment		6,354,042	6,057,932
Accumulated depreciation and amortization		(999,557)	(947,664)
Total real estate assets held for investment, net ($176,947 and $211,755 of VIE, respectively, Note 1)		5,354,485	5,110,268
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET		0	8,211
CASH AND CASH EQUIVALENTS		567,940	23,781
RESTRICTED CASH (Note 1)		8,130	75,185
MARKETABLE SECURITIES (Note 12)		12,638	11,971
CURRENT RECEIVABLES, NET (Note 5)		11,533	7,229	[1],[2],[3]
DEFERRED RENT RECEIVABLES, NET (Note 5)		183,352	156,416
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET (Note 4)		173,457	201,926
DEFERRED FINANCING COSTS, NET		18,709	18,374
PREPAID EXPENSES AND OTHER ASSETS, NET		23,148	20,375
TOTAL ASSETS		6,353,392	5,633,736
LIABILITIES:
Secured debt (Notes 6 and 12)	[4]	475,923	546,292
Unsecured debt, net (Notes 6 and 12)		2,181,382	1,783,121
Unsecured line of credit (Notes 6 and 12)		0	140,000
Accounts payable, accrued expenses and other liabilities		249,980	225,830
Accrued distributions (Note 15)		34,993	32,899
Deferred revenue and acquisition-related intangible liabilities, net (Note 4)		127,473	132,239
Rents received in advance and tenant security deposits		46,579	49,363
Liabilities of real estate assets held for sale		0	56
Total liabilities		$ 3,116,330	$ 2,909,800
COMMITMENTS AND CONTINGENCIES (Note 11)
Preferred stock, $.01 par value, 30,000,000 shares authorized:
Common stock, $.01 par value, 150,000,000 shares authorized, 92,220,367 and 86,259,684 shares issued and outstanding, respectively		$ 922	$ 863
Additional paid-in capital		3,042,330	2,635,900
Distributions in excess of earnings		(62,850)	(162,964)
Total stockholders’ equity		3,172,813	2,666,210
Noncontrolling interest :
Common units of the Operating Partnership (Note 7)		57,913	51,864
Noncontrolling interest in consolidated subsidiary (Note 1)		6,336	5,862
Total noncontrolling interests		64,249	57,726
Total equity		3,237,062	2,723,936
TOTAL LIABILITIES AND EQUITY		6,353,392	5,633,736
Series G Cumulative Redeemable Preferred Stock
Preferred stock, $.01 par value, 30,000,000 shares authorized:
Cumulative Redeemable Preferred stock		96,155	96,155
Series H Cumulative Redeemable Preferred Stock
Preferred stock, $.01 par value, 30,000,000 shares authorized:
Cumulative Redeemable Preferred stock		$ 96,256	$ 96,256
[1]	All interest rates presented are fixed-rate interest rates.
[2]	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.
[3]	This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs.
[4]	Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014, respectively.

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Carrying amounts of consolidated VIE	$ 180,488,000	$ 211,755,000
Common stock, par value	$ 0.01
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	88,405,632	86,259,684
Common stock, shares outstanding	88,405,632	86,259,684
Preferred Stock [Member]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	30,000,000	30,000,000
Series G Cumulative Redeemable Preferred Stock
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock dividend rate percentage	6.875%	6.875%
Preferred stock, shares authorized	4,600,000	4,600,000
Preferred stock, shares issued	4,000,000	4,000,000
Preferred stock, shares outstanding	4,000,000	4,000,000
Preferred Stock Liquidation preference	$ 100,000,000	$ 100,000,000
Series H Cumulative Redeemable Preferred Stock
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock dividend rate percentage	6.375%	6.375%
Preferred stock, shares authorized	4,000,000	4,000,000
Preferred stock, shares issued	4,000,000	4,000,000
Preferred stock, shares outstanding	4,000,000	4,000,000
Preferred Stock Liquidation preference	$ 100,000,000	$ 100,000,000

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
REVENUES:
Rental income		$ 129,510	$ 115,221	$ 391,892	$ 338,911
Tenant reimbursements		11,681	11,346	40,280	33,399
Other property income		362	2,457	1,690	7,650
Total revenues		141,553	129,024	433,862	379,960
EXPENSES
Property expenses		26,684	25,801	78,264	75,448
Real estate taxes		12,087	11,008	37,232	32,728
Provision for bad debts		0	58	289	58
Ground leases		862	771	2,451	2,306
General and administrative expenses		10,799	11,138	36,200	33,806
Acquisition-related expenses		4	431	397	1,268
Depreciation and amortization		49,422	50,032	152,567	148,647
Total expenses		99,858	99,239	307,400	294,261
OTHER (EXPENSES) INCOME:
Interest income and other net investment (loss) gain (Note 12)		(694)	(9)	177	587
Interest expense (Note 6)		(12,819)	(16,608)	(44,561)	(49,880)
Total other (expenses) income		(13,513)	(16,617)	(44,384)	(49,293)
INCOME FROM CONTINUING OPERATIONS BEFORE GAINS ON SALES OF REAL ESTATE		28,182	13,168	82,078	36,406
Gain on sale of land (Note 3)		0	0	17,268	3,490
Gains on sales of depreciable operating properties		78,522	0	109,950	0
INCOME FROM CONTINUING OPERATIONS		106,704	13,168	209,296	39,896
DISCONTINUED OPERATIONS (Note 1)
Income from discontinued operations		0	548	0	2,091
Gains on dispositions of discontinued operations		0	5,587	0	110,391
Total income from discontinued operations	[1]	0	6,135	0	112,482
NET INCOME		106,704	19,303	209,296	152,378
Net income attributable to noncontrolling common units of the Operating Partnership		(1,945)	(321)	(3,850)	(3,011)
NET INCOME		104,759	18,982	205,446	149,367
PREFERRED DIVIDENDS		(3,313)	(3,313)	(9,938)	(9,938)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS		$ 101,446	$ 15,669	$ 195,508	$ 139,429
Income (loss) from continuing operations available to common stockholders per common share – basic (Note 13)		$ 1.10	$ 0.11	$ 2.18	$ 0.34
Income from continuing operations available to common stockholders per common share – diluted (Note 13)		1.09	0.11	2.17	0.33
Net income available to common stockholders per share – basic (Note 13)		1.10	0.18	2.18	1.67
Net income available to common stockholders per share – diluted (Note 13)		$ 1.09	$ 0.18	$ 2.17	$ 1.63
Weighted average common shares outstanding – basic (Note 13)		92,150,341	83,161,323	89,077,012	82,525,033
Weighted average common shares outstanding – diluted (Note 13)		92,639,065	85,110,456	89,593,261	84,622,622
Dividends declared per common share		$ 0.35	$ 0.35	$ 1.05	$ 1.05
[1]	The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 1). 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.

Consolidated Statements of Equi

Consolidated Statements of Equity (Unaudited) - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Common Stock Additional Paid-in Capital	Common Stock Distributions in Excess of Earnings	Total Stockholders' Equity	Noncontrolling Interest [Member]	Kilroy Realty, L.P. [Member]	Kilroy Realty, L.P. [Member]Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2013	$ 2,516,160	$ 192,411	$ 822	$ 2,478,975	$ (210,896)	$ 2,461,312	$ 54,848
Beginning Balance, shares at Dec. 31, 2013			82,153,944
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	152,378				149,367	149,367	3,011	$ 152,378	$ 201
Issuance of common stock, shares (Note 8)			370,700
Issuance of common stock (Note 8)	22,136		$ 4	22,132		22,136
Issuance of share-based compensation awards	1,281			1,281		1,281
Noncash amortization of share-based compensation	10,345			10,345		10,345		10,345
Exercise of stock options (Note 10)			482,000
Exercise of stock options (Note 10)	20,537		$ 4	20,533		20,537
Repurchase of common stock and restricted stock units, shares			(48,017)
Repurchase of common stock and restricted stock units	(2,861)			(2,861)		(2,861)
Settlement of restricted stock units for shares of common stock, shares			108,529
Settlement of restricted stock units for shares of common stock	0			0		0		0
Stock Issued During Period, Shares, in Connection with Early Exchange of Notes			431,270
Stock Issued During Period, Value, in Connection with Early Exchange of Notes	223		$ 4	219		223		223
Stock Received During Period, Call Options			(111,206)
Exchange of common units of the Operating Parternship, shares			1,000
Exchange of common units of the Operating Partnership	0			28		28	(28)
Adjustment for noncontrolling interest	0			(370)		(370)	370
Contribution by noncontrolling interest in consolidated subsidiary	336						336	336	336
Preferred dividends	(9,938)				(9,938)	(9,938)		(9,938)
Dividends declared per common share and common unit ($1.05 per share/unit)	(90,228)				(88,332)	(88,332)	(1,896)
Ending Balance, shares at Sep. 30, 2014			83,388,220
Ending Balance at Sep. 30, 2014	2,620,369	192,411	$ 834	2,530,282	(159,799)	2,563,728	56,641
Beginning Balance at Dec. 31, 2014	2,723,936	192,411	$ 863	2,635,900	(162,964)	2,666,210	57,726
Beginning Balance, shares at Dec. 31, 2014			86,259,684
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	209,296				205,446	205,446	3,850	209,296	211
Issuance of common stock, shares (Note 8)			5,640,033
Issuance of common stock (Note 8)	387,509		$ 56	387,453		387,509
Issuance of share-based compensation awards	1,268			1,268		1,268
Noncash amortization of share-based compensation	13,621			13,621		13,621		13,621
Exercise of stock options (Note 10)			265,000
Exercise of stock options (Note 10)	11,292		$ 3	11,289		11,292
Repurchase of common stock and restricted stock units, shares			(39,317)
Repurchase of common stock and restricted stock units	(3,121)			(3,121)		(3,121)
Settlement of restricted stock units for shares of common stock, shares			78,937
Settlement of restricted stock units for shares of common stock	0			0		0		0
Exchange of common units of the Operating Parternship, shares			16,030
Exchange of common units of the Operating Partnership	0			467		467	(467)
Adjustment for noncontrolling interest	0			(4,547)		(4,547)	4,547
Contribution by noncontrolling interest in consolidated subsidiary	474							474	$ 474
Preferred dividends	(9,938)				(9,938)	(9,938)		$ (9,938)
Dividends declared per common share and common unit ($1.05 per share/unit)	(97,275)				(95,394)	(95,394)	(1,881)
Ending Balance, shares at Sep. 30, 2015			92,220,367
Ending Balance at Sep. 30, 2015	$ 3,237,062	$ 192,411	$ 922	$ 3,042,330	$ (62,850)	$ 3,172,813	$ 64,249

Consolidated Statements of Equ6

Consolidated Statements of Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share	$ 0.35	$ 0.35	$ 1.05	$ 1.05

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 209,296	$ 152,378
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of building and improvements and leasing costs	150,531	148,878
Increase in provision for bad debts	289	58
Depreciation of furniture, fixtures and equipment	2,036	1,731
Noncash amortization of share-based compensation awards	11,272	8,817
Noncash amortization of deferred financing costs and debt discounts and premiums	1,412	3,563
Noncash amortization of net below market rents (Note 4)	(6,769)	(6,216)
Gain on sale of land (Note 3)	(17,268)	(3,490)
Gains on sales of depreciable operating properties (Note 3)	(109,950)	0
Gains on dispositions of discontinued operations (Note 1)	0	(110,391)
Noncash amortization of deferred revenue related to tenant-funded tenant improvements	(9,957)	(7,695)
Straight-line rents	(35,530)	(15,245)
Net change in other operating assets	(9,356)	(795)
Net change in other operating liabilities	16,606	25,671
Net cash provided by operating activities	202,612	197,264
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development and redevelopment properties and undeveloped land	(311,916)	(292,803)
Expenditures for acquisition of development properties (Note 2)	(130,609)	(97,727)
Expenditures for operating properties	(71,756)	(93,977)
Expenditures for acquisition of operating properties	0	(106,125)
Net proceeds received from dispositions of land and operating properties (Note 3)	319,639	368,381
Decrease in acquisition-related deposits	3,200	1,000
Issuance of note receivable	3,000	0
Decrease in restricted cash (Note 1)	57,776	32,293
Net cash used in investing activities	(136,666)	(188,958)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock (Note 8)	387,509	22,136
Borrowings on unsecured revolving credit facility	250,000	365,000
Repayments on unsecured revolving credit facility	(390,000)	(410,000)
Principal payments on secured debt (Note 6)	(67,335)	(7,315)
Net proceeds from the issuance of unsecured debt (Note 6)	397,776	395,528
Repayments of unsecured debt (Note 6)	0	83,000
Repayments for early redemption of exchangeable senior notes	0	37,092
Financing costs	(4,534)	(8,043)
Repurchase of common stock and restricted stock units	(3,121)	(2,861)
Proceeds from exercise of stock options (Note 10)	11,292	20,537
Contributions from noncontrolling interests in consolidated subsidiary	474	336
Dividends and distributions paid to common stockholders and common unitholders	(93,910)	(88,540)
Dividends and distributions paid to preferred stockholders and preferred unitholders	(9,938)	(9,938)
Net cash provided by financing activities	478,213	156,748
Net increase in cash and cash equivalents	544,159	165,054
Cash and cash equivalents, beginning of period	23,781	35,377
Cash and cash equivalents, end of period	567,940	200,431
SUPPLEMENTAL CASH FLOWS INFORMATION:
Cash paid for interest, net of capitalized interest of $37,010 and $33,533 as of September 30, 2015 and 2014, respectively	45,678	42,633
NONCASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	89,009	92,693
Tenant improvements funded directly by tenants	12,944	23,069
Assumption of other liabilities in connection with development acquisitions	5,070	2,300
Release of holdback funds to third party	9,279	0
NONCASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common stockholders and common unitholders	33,353	30,258
Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders	1,656	1,656
Exchange of common units of the Operating Partnership into shares of the Company’s common stock	$ 467	$ 28

Consolidated Statements of Cas8

Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
SUPPLEMENTAL CASH FLOWS INFORMATION:
Cash paid for interest - capitalized interest amount	$ 22,753	$ 20,976

Consolidated Balance Sheets (KI

Consolidated Balance Sheets (KILROY REALTY, L.P.) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
REAL ESTATE ASSETS:
Land and improvements		$ 850,280	$ 877,633
Buildings and improvements		4,028,044	4,059,639
Undeveloped land and construction in progress (Note 2)		1,475,718	1,120,660
Total real estate assets held for investment		6,354,042	6,057,932
Accumulated depreciation and amortization		(999,557)	(947,664)
Total real estate assets held for investment, net ($176,947 and $211,755 of VIE, respectively, Note 1)		5,354,485	5,110,268
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET		0	8,211
CASH AND CASH EQUIVALENTS		567,940	23,781
RESTRICTED CASH (Note 1)		8,130	75,185
MARKETABLE SECURITIES (Note 12)		12,638	11,971
CURRENT RECEIVABLES, NET (Note 5)		11,533	7,229	[1],[2],[3]
DEFERRED RENT RECEIVABLES, NET (Note 5)		183,352	156,416
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET (Note 4)		173,457	201,926
DEFERRED FINANCING COSTS, NET		18,709	18,374
PREPAID EXPENSES AND OTHER ASSETS, NET		23,148	20,375
TOTAL ASSETS		6,353,392	5,633,736
LIABILITIES:
Secured debt (Notes 6 and 12)	[4]	475,923	546,292
Unsecured debt, net (Notes 6 and 12)		2,181,382	1,783,121
Unsecured line of credit (Notes 6 and 12)		0	140,000
Accounts payable, accrued expenses and other liabilities		249,980	225,830
Accrued distributions (Note 15)		34,993	32,899
Deferred revenue and acquisition-related intangible liabilities, net (Note 4)		127,473	132,239
Rents received in advance and tenant security deposits		46,579	49,363
Liabilities of real estate assets held for sale		0	56
Total liabilities		$ 3,116,330	$ 2,909,800
COMMITMENTS AND CONTINGENCIES (Note 11)
Partners’ Capital (Note 9):
TOTAL LIABILITIES AND EQUITY		$ 6,353,392	$ 5,633,736
Kilroy Realty, L.P. [Member]
REAL ESTATE ASSETS:
Land and improvements		850,280	877,633
Buildings and improvements		4,028,044	4,059,639
Undeveloped land and construction in progress (Note 2)		1,475,718	1,120,660
Total real estate assets held for investment		6,354,042	6,057,932
Accumulated depreciation and amortization		(999,557)	(947,664)
Total real estate assets held for investment, net ($176,947 and $211,755 of VIE, respectively, Note 1)		5,354,485	5,110,268
REAL ESTATE ASSETS AND OTHER ASSETS HELD FOR SALE, NET		0	8,211
CASH AND CASH EQUIVALENTS		567,940	23,781
RESTRICTED CASH (Note 1)		8,130	75,185
MARKETABLE SECURITIES (Note 12)		12,638	11,971
CURRENT RECEIVABLES, NET (Note 5)		11,533	7,229
DEFERRED RENT RECEIVABLES, NET (Note 5)		183,352	156,416
DEFERRED LEASING COSTS AND ACQUISITION-RELATED INTANGIBLE ASSETS, NET (Note 4)		173,457	201,926
DEFERRED FINANCING COSTS, NET		18,709	18,374
PREPAID EXPENSES AND OTHER ASSETS, NET		23,148	20,375
TOTAL ASSETS		6,353,392	5,633,736
LIABILITIES:
Secured debt (Notes 6 and 12)		475,923	546,292
Unsecured debt, net (Notes 6 and 12)		2,181,382	1,783,121
Unsecured line of credit (Notes 6 and 12)		0	140,000
Accounts payable, accrued expenses and other liabilities		249,980	225,830
Accrued distributions (Note 15)		34,993	32,899
Deferred revenue and acquisition-related intangible liabilities, net (Note 4)		127,473	132,239
Rents received in advance and tenant security deposits		46,579	49,363
Liabilities of real estate assets held for sale		0	56
Total liabilities		3,116,330	2,909,800
Partners’ Capital (Note 9):
Common units, 92,220,367 and 86,259,684 held by the general partner and 1,788,170 and 1,804,200 held by common limited partners issued and outstanding, respectively		3,034,341	2,521,900
Total partners’ capital		3,226,752	2,714,311
Noncontrolling interests in consolidated subsidiaries (Note 1)		10,310	9,625
Total capital		3,237,062	2,723,936
TOTAL LIABILITIES AND EQUITY		6,353,392	5,633,736
Series G Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Partners’ Capital (Note 9):
Redeemable Preferred stock		96,155	96,155
Series H Cumulative Redeemable Preferred Unit [Member] | Kilroy Realty, L.P. [Member]
Partners’ Capital (Note 9):
Redeemable Preferred stock		$ 96,256	$ 96,256
[1]	All interest rates presented are fixed-rate interest rates.
[2]	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.
[3]	This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs.
[4]	Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014, respectively.

Consolidated Balance Sheets (10

Consolidated Balance Sheets (KILROY REALTY, L.P.) (Parenthetical) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Carrying amounts of consolidated VIE	$ 180,488,000	$ 211,755,000
Common units held by limited partners	1,788,170	1,804,200
Common stock, par value	$ 0.01
Kilroy Realty, L.P. [Member]
Carrying amounts of consolidated VIE	$ 180,488,000	$ 211,755,000
Kilroy Realty, L.P. [Member] | Common Units [Member]
General partner, units issued	88,405,632	86,259,684
General partners, units outstanding	88,405,632	86,259,684
Limited partners, units issued	1,793,170	1,804,200
Common units held by limited partners	1,793,170	1,804,200
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	$ 100,000,000	$ 100,000,000
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	$ 100,000,000	$ 100,000,000

Consolidated Statements of Op11

Consolidated Statements of Operations (KILROY REALTY, L.P.) - USD ($) $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014
REVENUES:
Rental income		$ 129,510		$ 115,221		$ 391,892	$ 338,911
Tenant reimbursements		11,681		11,346		40,280	33,399
Other property income		362		2,457		1,690	7,650
Total revenues		141,553		129,024		433,862	379,960
EXPENSES
Property expenses		26,684		25,801		78,264	75,448
Real estate taxes		12,087		11,008		37,232	32,728
Provision for bad debts		0		58		289	58
Ground leases		862		771		2,451	2,306
General and administrative expenses		10,799		11,138		36,200	33,806
Acquisition-related expenses		4		431		397	1,268
Depreciation and amortization		49,422		50,032		152,567	148,647
Total expenses		99,858		99,239		307,400	294,261
OTHER (EXPENSES) INCOME:
Interest income and other net investment gain (Note 12)		(694)		(9)		177	587
Interest expense (Note 6)		(12,819)		(16,608)		(44,561)	(49,880)
Total other (expenses) income		(13,513)		(16,617)		(44,384)	(49,293)
Gain on sale of land (Note 3)		0		0		17,268	3,490
Gain (Loss) on Disposition of Property Plant Equipment		78,522		0		109,950	0
INCOME FROM CONTINUING OPERATIONS		106,704		13,168		209,296	39,896
DISCONTINUED OPERATIONS (Note 1)
Income from discontinued operations		0		548		0	2,091
Gains on dispositions of discontinued operations		0		5,587		0	110,391
Total income from discontinued operations	[1]	0		6,135		0	112,482
NET INCOME		106,704		19,303		209,296	152,378
NET INCOME		104,759		18,982		205,446	149,367
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS		$ 101,446		$ 15,669		$ 195,508	$ 139,429
Income (loss) from continuing operations available to common unitholders per unit - basic (Note 14)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income (loss) from continuing operations available to common unitholders per unit - diluted (Note 15)		1.09		0.11		2.17	0.33
Net income available to common unitholders per unit-basic (Note 14)		1.10		0.18		2.18	1.67
Net income available to common unitholders per unit-diluted (Note 14)		$ 1.09		$ 0.18		$ 2.17	$ 1.63
Weighted average common units outstanding - basic (Note 14)		92,150,341		83,161,323		89,077,012	82,525,033
Weighted average common units outstanding - diluted (Note 14)		92,639,065		85,110,456		89,593,261	84,622,622
Kilroy Realty, L.P. [Member]
REVENUES:
Rental income		$ 129,510		$ 115,221		$ 391,892	$ 338,911
Tenant reimbursements		11,681		11,346		40,280	33,399
Other property income		362		2,457		1,690	7,650
Total revenues		141,553		129,024		433,862	379,960
EXPENSES
Property expenses		26,684		25,801		78,264	75,448
Real estate taxes		12,087		11,008		37,232	32,728
Provision for bad debts		0		58		289	58
Ground leases		862		771		2,451	2,306
General and administrative expenses		10,799		11,138		36,200	33,806
Acquisition-related expenses		4		431		397	1,268
Depreciation and amortization		49,422		50,032		152,567	148,647
Total expenses		99,858		99,239		307,400	294,261
OTHER (EXPENSES) INCOME:
Interest income and other net investment gain (Note 12)		(694)		(9)		177	587
Interest expense (Note 6)		(12,819)		(16,608)		(44,561)	(49,880)
Total other (expenses) income		(13,513)		(16,617)		(44,384)	(49,293)
INCOME FROM CONTINUING OPERATIONS BEFORE GAINS ON SALES OF REAL ESTATE		28,182		13,168		82,078	36,406
Gain on sale of land (Note 3)		0		0		17,268	3,490
Gain (Loss) on Disposition of Property Plant Equipment		78,522		0		109,950	0
INCOME FROM CONTINUING OPERATIONS		106,704		13,168		209,296	39,896
DISCONTINUED OPERATIONS (Note 1)
Income from discontinued operations		0		548		0	2,091
Gains on dispositions of discontinued operations		0		5,587		0	110,391
Total income from discontinued operations		0	[2]	6,135	[2]	0	112,482	[2]
NET INCOME		106,704		19,303		209,296	152,378
Net income attributable to noncontrolling interests in consolidated subsidiaries		(64)		(59)		(211)	(201)
NET INCOME		106,640		19,244		209,085	152,177
Preferred Distributions		(3,313)		(3,313)		(9,938)	(9,938)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS		$ 103,327		$ 15,931		$ 199,147	$ 142,239
Income (loss) from continuing operations available to common unitholders per unit - basic (Note 14)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income (loss) from continuing operations available to common unitholders per unit - diluted (Note 15)		1.09		0.11		2.17	0.33
Net income available to common unitholders per unit-basic (Note 14)		1.10		0.18		2.18	1.67
Net income available to common unitholders per unit-diluted (Note 14)		$ 1.09		$ 0.18		$ 2.17	$ 1.63
Weighted average common units outstanding - basic (Note 14)		93,938,783		84,965,523		90,869,696	84,329,317
Weighted average common units outstanding - diluted (Note 14)		94,427,507		86,914,656		91,385,945	86,426,906
Dividends declared per common unit		$ 0.35		$ 0.35		$ 1.05	$ 1.05
[1]	The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 1). 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.
[2]	The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 1). 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.

Consolidated Statements of Capi

Consolidated Statements of Capital (KILROY REALTY, L.P.) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 106,704	$ 19,303	$ 209,296	$ 152,378
Noncash amortization of share-based compensation			13,621	10,345
Settlement of restricted stock units for shares of common stock			0	0
Stock Issued During Period, Value, in Connection with Early Exchange of Notes				223
Contribution by noncontrolling interest in consolidated subsidiary			474	336
Preferred distributions			(9,938)	(9,938)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			3,850	3,011
Contribution by noncontrolling interest in consolidated subsidiary				336
Kilroy Realty, L.P. [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			2,723,936	2,516,160
Net income	106,704	19,303	209,296	152,378
Issuance of common units (Note 9)			387,509	22,136
Issuance of share-based compensation awards			1,268	1,281
Noncash amortization of share-based compensation			13,621	10,345
Exercise of stock options (Note 10)			11,292	20,537
Repurchase of common units and restricted stock units			(3,121)	(2,861)
Settlement of restricted stock units for shares of common stock			0	0
Stock Issued During Period, Value, in Connection with Early Exchange of Notes				223
Contribution by noncontrolling interest in consolidated subsidiary			474	336
Preferred distributions			(9,938)	(9,938)
Distributions declared per common unit ($0.35 per unit)			(97,275)	(90,228)
Ending Balance	3,237,062	2,620,369	3,237,062	2,620,369
Kilroy Realty, L.P. [Member] | Partners Capital Preferred Units [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			192,411	192,411
Ending Balance	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			$ 2,521,900	$ 2,315,361
Beginning Balance units			88,063,884	83,959,144
Net income			$ 209,085	$ 152,177
Issuance of common units, units (Note 9)			5,640,033	370,700
Issuance of common units (Note 9)			$ 387,509	$ 22,136
Issuance of share-based compensation awards			1,268	1,281
Noncash amortization of share-based compensation			$ 13,621	$ 10,345
Exercise of stock options (Note 10)			265,000	482,000
Exercise of stock options (Note 10)			$ 11,292	$ 20,537
Repurchase of common units and restricted stock units, units			(39,317)	(48,017)
Repurchase of common units and restricted stock units			$ (3,121)	$ (2,861)
Settlement of restricted stock units, units			78,937	108,529
Settlement of restricted stock units for shares of common stock			$ 0	$ 0
Stock Issued During Period, Shares, in Connection with Early Exchange of Notes				431,270
Stock Issued During Period, Value, in Connection with Early Exchange of Notes				$ 223
Stock Received During Period, Call Options				(111,206)
Preferred distributions			(9,938)	$ (9,938)
Distributions declared per common unit ($0.35 per unit)			(97,275)	(90,228)
Ending Balance	$ 3,034,341	$ 2,419,033	$ 3,034,341	$ 2,419,033
Ending Balance units	94,008,537	85,192,420	94,008,537	85,192,420
Kilroy Realty, L.P. [Member] | Total Partners Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			$ 2,714,311	$ 2,507,772
Net income			209,085	152,177
Issuance of common units (Note 9)			387,509	22,136
Issuance of share-based compensation awards			1,268	1,281
Noncash amortization of share-based compensation			13,621	10,345
Exercise of stock options (Note 10)			11,292	20,537
Repurchase of common units and restricted stock units			(3,121)	(2,861)
Settlement of restricted stock units for shares of common stock			0	0
Stock Issued During Period, Value, in Connection with Early Exchange of Notes				223
Preferred distributions			(9,938)	(9,938)
Distributions declared per common unit ($0.35 per unit)			(97,275)	(90,228)
Ending Balance	$ 3,226,752	$ 2,611,444	3,226,752	2,611,444
Kilroy Realty, L.P. [Member] | Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			9,625	8,388
Net income			211	201
Contribution by noncontrolling interest in consolidated subsidiary			474	336
Ending Balance	$ 10,310	$ 8,925	$ 10,310	$ 8,925

Consolidated Statements of Ca13

Consolidated Statements of Capital (KILROY REALTY, L.P.) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Kilroy Realty, L.P. [Member]
Distributions Per Limited Partnership and General Partnership Unit, Outstanding, Basic	$ 0.35	$ 0.35	$ 1.05	$ 1.05

Consolidated Statements of Ca14

Consolidated Statements of Cash Flows (KILROY REALTY, L.P.) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 209,296	$ 152,378
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of building and improvements and leasing costs	150,531	148,878
Increase in provision for bad debts	289	58
Depreciation of furniture, fixtures and equipment	2,036	1,731
Noncash amortization of share-based compensation awards	11,272	8,817
Noncash amortization of deferred financing costs and debt discounts and premiums	1,412	3,563
Noncash amortization of net below market rents (Note 4)	(6,769)	(6,216)
Gain on sale of land (Note 3)	(17,268)	(3,490)
Gains on sales of depreciable operating properties (Note 3)	(109,950)	0
Gains on dispositions of discontinued operations (Note 1)	0	(110,391)
Noncash amortization of deferred revenue related to tenant-funded tenant improvements	(9,957)	(7,695)
Straight-line rents	(35,530)	(15,245)
Net change in other operating assets	(9,356)	(795)
Net change in other operating liabilities	16,606	25,671
Net cash provided by operating activities	202,612	197,264
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development and redevelopment properties and undeveloped land	(311,916)	(292,803)
Expenditures for acquisition of development properties (Note 2)	(130,609)	(97,727)
Expenditures for operating properties	(71,756)	(93,977)
Expenditures for acquisition of operating properties	0	(106,125)
Net proceeds received from dispositions of land and operating properties (Note 3)	319,639	368,381
Decrease in acquisition-related deposits	3,200	1,000
Issuance of Note Receivable	(3,000)	0
Decrease in restricted cash (Note 1)	57,776	32,293
Net cash used in investing activities	(136,666)	(188,958)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on unsecured revolving credit facility	250,000	365,000
Repayments on unsecured revolving credit facility	(390,000)	(410,000)
Principal payments on secured debt (Note 6)	(67,335)	(7,315)
Net proceeds from the issuance of unsecured debt (Note 6)	397,776	395,528
Repayments of unsecured debt (Note 6)	0	83,000
Repayments for early redemption of exchangeable senior notes	0	37,092
Financing costs	(4,534)	(8,043)
Repurchase of common stock and restricted stock units	(3,121)	(2,861)
Proceeds from exercise of stock options (Note 10)	11,292	20,537
Contributions from noncontrolling interests in consolidated subsidiary	474	336
Dividends and distributions paid to common unitholders	(93,910)	(88,540)
Dividends and distributions paid to preferred unitholders	(9,938)	(9,938)
Net cash provided by financing activities	478,213	156,748
Net increase in cash and cash equivalents	544,159	165,054
Cash and cash equivalents, beginning of period	23,781	35,377
Cash and cash equivalents, end of period	567,940	200,431
SUPPLEMENTAL CASH FLOWS INFORMATION:
Cash paid for interest, net of capitalized interest of $37,010 and $33,533 as of September 30, 2015 and 2014, respectively	45,678	42,633
NONCASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	89,009	92,693
Tenant improvements funded directly by tenants	12,944	23,069
Assumption of other liabilities in connection with development acquisitions	5,070	2,300
Release of Holdback Funds to Third Party	9,279	0
NONCASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common unitholders	33,353	30,258
Accrual of dividends and distributions payable to preferred unitholders	1,656	1,656
Kilroy Realty, L.P. [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	209,296	152,378
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of building and improvements and leasing costs	150,531	148,878
Increase in provision for bad debts	289	58
Depreciation of furniture, fixtures and equipment	2,036	1,731
Noncash amortization of share-based compensation awards	11,272	8,817
Noncash amortization of deferred financing costs and debt discounts and premiums	1,412	3,563
Noncash amortization of net below market rents (Note 4)	(6,769)	(6,216)
Gain on sale of land (Note 3)	(17,268)	(3,490)
Gains on sales of depreciable operating properties (Note 3)	(109,950)	0
Gains on dispositions of discontinued operations (Note 1)	0	(110,391)
Noncash amortization of deferred revenue related to tenant-funded tenant improvements	(9,957)	(7,695)
Straight-line rents	(35,530)	(15,245)
Net change in other operating assets	(9,356)	(795)
Net change in other operating liabilities	16,606	25,671
Net cash provided by operating activities	202,612	197,264
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development and redevelopment properties and undeveloped land	(311,916)	(292,803)
Expenditures for acquisition of development properties (Note 2)	(130,609)	(97,727)
Expenditures for operating properties	(71,756)	(93,977)
Expenditures for acquisition of operating properties	0	(106,125)
Net proceeds received from dispositions of land and operating properties (Note 3)	319,639	368,381
Decrease in acquisition-related deposits	3,200	1,000
Issuance of Note Receivable	3,000
Decrease in restricted cash (Note 1)	57,776	32,293
Net cash used in investing activities	(136,666)	(188,958)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock (Note 8)	387,509	22,136
Borrowings on unsecured revolving credit facility	250,000	365,000
Repayments on unsecured revolving credit facility	(390,000)	(410,000)
Principal payments on secured debt (Note 6)	(67,335)	(7,315)
Net proceeds from the issuance of unsecured debt (Note 6)	397,776	395,528
Repayments of unsecured debt (Note 6)	0	83,000
Repayments for early redemption of exchangeable senior notes	0	37,092
Financing costs	(4,534)	(8,043)
Repurchase of common stock and restricted stock units	(3,121)	(2,861)
Proceeds from exercise of stock options (Note 10)	11,292	20,537
Contributions from noncontrolling interests in consolidated subsidiary	474	336
Dividends and distributions paid to common unitholders	(93,910)	(88,540)
Dividends and distributions paid to preferred unitholders	(9,938)	(9,938)
Net cash provided by financing activities	478,213	156,748
Net increase in cash and cash equivalents	544,159	165,054
Cash and cash equivalents, beginning of period	23,781	35,377
Cash and cash equivalents, end of period	567,940	200,431
SUPPLEMENTAL CASH FLOWS INFORMATION:
Cash paid for interest, net of capitalized interest of $37,010 and $33,533 as of September 30, 2015 and 2014, respectively	45,678	42,633
NONCASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	89,009	92,693
Tenant improvements funded directly by tenants	12,944	23,069
Assumption of other liabilities in connection with development acquisitions	5,070	2,300
Release of Holdback Funds to Third Party	9,279	0
NONCASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common unitholders	33,353	30,258
Accrual of dividends and distributions payable to preferred unitholders	$ 1,656	$ 1,656

Consolidated Statements of Ca15

Consolidated Statements of Cash Fiows (Kilroy Realty, L.P.) (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash paid for interest - capitalized interest amount	$ 22,753	$ 20,976
Kilroy Realty, L.P. [Member]
Cash paid for interest - capitalized interest amount	$ 22,753	$ 20,976

Organization and Basis of Prese

Organization and Basis of Presentation	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Organization Kilroy Realty Corporation (the “Company”) is a self-administered real estate investment trust (“REIT”) active in premier office 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 office properties at September 30, 2015 : Number of Buildings Rentable Square Feet Number of Tenants Percentage Occupied Stabilized Office Properties 101 13,050,947 509 95.6 % 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. As of September 30, 2015 , we had no redevelopment properties. 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. As of September 30, 2015 , we had one development project in the “lease-up” phase. As of September 30, 2015 , the following properties were excluded from our stabilized portfolio: Number of Properties/Projects Estimated Rentable Square Feet Development projects in “ lease-up ” 1 108,539 Development projects under construction (1) 7 2,322,000 ________________________ (1) Estimated rentable square feet upon completion. Our stabilized portfolio also excludes our near-term and future development pipeline, which as of September 30, 2015 was comprised of ten development sites, representing approximately 106 gross acres of undeveloped land. As of September 30, 2015 , all of our stabilized portfolio 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 a recently acquired development opportunity located in the state of Washington. All of our properties and development projects are 100% owned, excluding a development project owned by Redwood City Partners, LLC (“Redwood LLC”), a consolidated subsidiary. As of September 30, 2015 , the Company owned an approximate 98.1% common general partnership interest in the Operating Partnership. The remaining approximate 1.9% common limited partnership interest in the Operating Partnership as of September 30, 2015 was owned by non-affiliated investors and certain of our executive officers and directors (see Note 7). 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 7). Kilroy Realty Finance, Inc., which is 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 in the Finance Partnership. The Operating Partnership owns the remaining 99.0% common limited partnership interest. Kilroy Services, LLC (“KSLLC”), which is a wholly owned subsidiary of the Operating Partnership, is the entity through which we generally conduct substantially all of our development activities. With the exception of the Operating Partnership and Redwood LLC, all of our subsidiaries are wholly owned. 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, 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, 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. The accompanying interim financial statements have been prepared by management in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and in conjunction with the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures required for annual financial statements have been condensed or excluded pursuant to SEC rules and regulations. Accordingly, the interim financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the accompanying interim financial statements reflect all adjustments of a normal and recurring nature that are considered necessary for a fair presentation of the results for the interim periods presented. However, the results of operations for the interim periods are not necessarily indicative of the results that may be expected for the year ending December 31, 2015. The interim financial statements for the Company and the Operating Partnership should be read in conjunction with the audited consolidated financial statements and notes thereto included in our annual report on Form 10-K for the year ended December 31, 2014 . Certain amounts in the consolidated statements of operations for prior periods have been reclassified to reflect the activity of discontinued operations disposed of prior to the Company's adoption of Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-08 (“ASU 2014-08”). Properties classified as held for sale and/or disposed of prior to January 1, 2015 are presented as discontinued operations for all periods presented. Variable Interest Entities At September 30, 2015 , the consolidated financial statements of the Company and the Operating Partnership included one variable interest entity (“VIE”), in which we were deemed to be the primary beneficiary. The VIE, Redwood LLC, was established in the second quarter of 2013 in connection with an undeveloped land acquisition. The impact of consolidating the VIE increased the Company’s total assets, liabilities and noncontrolling interests by approximately $180.7 million (of which $176.9 million related to real estate held for investment on our consolidated balance sheet), approximately $43.5 million and approximately $6.3 million , respectively, as of September 30, 2015 . As of December 31, 2014 , 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 of the VIEs was Redwood LLC and the remaining VIE was established during the fourth quarter of 2014 to facilitate potential Section 1031 Exchanges. During the three months ended March 31, 2015, the Section 1031 Exchange was successfully completed and the VIE was terminated. As a result, $59.2 million of our restricted cash balance at December 31, 2014 , which related to prior period disposition proceeds that were set aside to facilitate the Section 1031 Exchange, was released from escrow. The impact of consolidating the VIEs increased the Company’s total assets, liabilities and noncontrolling interests by approximately $219.6 million (of which $211.8 million related to real estate held for investment on our consolidated balance sheet), approximately $23.4 million and approximately $5.9 million , respectively, as of December 31, 2014 . Adoption of New Accounting Pronouncements Effective January 1, 2015, the Company adopted FASB ASU 2014-08, which changed the criteria for reporting discontinued operations while enhancing disclosures in this area. Under the new guidance, only disposals representing a strategic shift that has (or will have) a major effect on an entity's operations and final results, such as a major line of business, a major geographical area or a major equity investment, should be presented as discontinued operations. The Company adopted and applied the new guidance on a prospective basis as required by ASU 2014-08. Therefore, real estate assets classified as held for sale and/or disposed of subsequent to January 1, 2015 that do not represent a strategic shift will be presented in continuing operations for all periods presented. Properties classified as held for sale and/or disposed of prior to January 1, 2015 will continue to be presented in discontinued operations for prior periods presented. In accordance with this guidance, the operations of the ten properties sold during the nine months ended September 30, 2015 are presented in continuing operations for the nine months ended September 30, 2015 . For the nine months ended September 30, 2014 , discontinued operations includes the income and gains on all of the properties sold in 2014. Recently Issued Accounting Pronouncements On August 12, 2015, the FASB issued ASU No. 2015-14 (“ASU 2015-14”) to defer the effective date 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 assessing the impact of the guidance on our consolidated financial statements and notes to our consolidated financial statements. On April 7, 2015, the FASB issued ASU No. 2015-03 (“ASU 2015-03”) to amend the accounting guidance for the presentation of debt issuance costs. The standard requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. On August 18, 2015, the FASB also issued ASU No. 2015-15 (“ASU 2015-15”) to address the presentation of debt issuance costs specifically related to line-of-credit arrangements. The standard clarifies that an entity 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 an outstanding borrowings on the line-of credit arrangement. ASU 2015-03 and ASU 2015-15 are effective for public business entities for fiscal years beginning after December 15, 2015 and retrospective application is required. Early adoption of the guidance is permitted. The Company expects to adopt the guidance effective January 1, 2016 and the guidance will not have any impact on our consolidated statements of operations, equity/capital, or cash flows. In February 2015, the FASB issued an update (“ASU 2015-02”) Amendments to the Consolidation Analysis to ASC Topic 810, Consolidation . ASU 2015-02 affects reporting entities that are required to evaluate whether they should 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 consolidated analysis of reporting entities that are involved with VIEs, and (iv) provide a scope exception for certain entities. ASU 2015-02 is effective for interim and annual reporting periods beginning after December 15, 2015. The Company is currently assessing the impact of the guidance on our consolidated financial statements and notes to our consolidated financial statements.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Acquisitions Development Project Acquisitions During the nine months ended September 30, 2015 , we acquired the development opportunities listed below from unrelated third parties. The acquisitions were funded with proceeds from various sources, including the Company’s unsecured revolving credit facility, at-the-market stock offering program (see Note 8) and prior year disposition proceeds. As of September 30, 2015 , the underlying assets were included as undeveloped land and construction in progress in our consolidated balance sheets. Project Date of Acquisition City/Submarket Type Purchase Price (in millions) 333 Dexter (1) February 13, 2015 South Lake Union, WA Land $ 49.5 100 Hooper (2) July 7, 2015 San Francisco, CA Land 78.0 Total Acquisitions $ 127.5 ________________________ (1) 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. (2) 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. The Company expects to develop and own two buildings on the site encompassing office and production design and repair space totaling approximately 400,000 square feet.

Dispositions

Dispositions	9 Months Ended
	Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Real Estate Assets Held for Sale and Dispositions	Operating Property Dispositions The following table summarizes the operating properties sold during the nine months ended September 30, 2015 : Location Property Type Month of Disposition Number of Buildings Rentable Square Feet 15050 NE 36th Street, Redmond, WA Office April 1 122,103 San Diego Properties - Tranche 1 (1) Office April 3 384,468 San Diego Properties - Tranche 2 (2) Office July 6 539,823 Total Dispositions 10 1,046,394 ________________________ (1) The San Diego Properties - Tranche 1 include the following: 10770 Wateridge Circle, 6200 Greenwich Drive, and 6220 Greenwich Drive. (2) The San Diego Properties - Tranche 2 include the following: 6260 Sequence Drive, 6290 Sequence, Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive, and 4921 Directors Place. The ten buildings encompassing 1,046,394 rentable square feet were sold for a gross sales price of $309.2 million , resulting in a gain on sale of $110.0 million . Land Disposition During the nine months ended September 30, 2015 , the Company sold a land parcel located at 17150 Von Karman in Irvine, California for a gross sales price of $26.0 million , resulting in a gain on sale of $17.3 million .

Deferred Leasing Costs and Acqu

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net	9 Months Ended
	Sep. 30, 2015
Intangible Assets and Liabilities 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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Deferred Leasing Costs and Acquisition-Related Intangible Assets, net: Deferred leasing costs $ 201,605 $ 216,102 Accumulated amortization (74,997 ) (74,904 ) Deferred leasing costs, net 126,608 141,198 Above-market operating leases 11,026 20,734 Accumulated amortization (6,380 ) (13,952 ) Above-market operating leases, net 4,646 6,782 In-place leases 74,071 97,250 Accumulated amortization (32,331 ) (43,773 ) In-place leases, net 41,740 53,477 Below-market ground lease obligation 490 490 Accumulated amortization (27 ) (21 ) Below-market ground lease obligation, net 463 469 Total deferred leasing costs and acquisition-related intangible assets, net $ 173,457 $ 201,926 Acquisition-Related Intangible Liabilities, net: (1) Below-market operating leases $ 55,136 $ 68,051 Accumulated amortization (26,632 ) (30,620 ) Below-market operating leases, net 28,504 37,431 Above-market ground lease obligation 6,320 6,320 Accumulated amortization (399 ) (324 ) Above-market ground lease obligation, net 5,921 5,996 Total acquisition-related intangible liabilities, net $ 34,425 $ 43,427 ________________________ (1) 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 three and nine months ended September 30, 2015 and 2014 , including amounts attributable to discontinued operations for 2014: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Deferred leasing costs (1) $ 6,932 $ 7,132 $ 20,847 $ 20,683 Above-market operating leases (2) 487 1,305 2,135 4,230 In-place leases (1) 3,073 5,169 11,710 17,090 Below-market ground lease obligation (3) 2 2 6 6 Below-market operating leases (4) (2,228 ) (2,940 ) (8,905 ) (10,054 ) Above-market ground lease obligation (5) (26 ) (26 ) (76 ) (76 ) Total $ 8,240 $ 10,642 $ 25,717 $ 31,879 ________________________ (1) The amortization of deferred leasing costs related to lease incentives is recorded to rental income and other deferred leasing costs and in-place leases is recorded to depreciation and amortization expense 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 September 30, 2015 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) Remaining 2015 $ 6,740 $ 399 $ 2,800 $ 2 $ (2,044 ) $ (25 ) 2016 25,662 1,499 10,449 8 (7,638 ) (101 ) 2017 22,661 1,241 9,113 8 (7,017 ) (101 ) 2018 19,023 831 6,373 8 (5,735 ) (101 ) 2019 15,150 643 4,714 8 (3,597 ) (101 ) Thereafter 37,372 33 8,291 429 (2,473 ) (5,492 ) Total $ 126,608 $ 4,646 $ 41,740 $ 463 $ (28,504 ) $ (5,921 ) ________________________ (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	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (1) (in thousands) Current receivables $ 13,372 $ 9,228 Allowance for uncollectible tenant receivables (1,839 ) (1,999 ) Current receivables, net $ 11,533 $ 7,229 ________________________ (1) Excludes current receivables, net related to properties held for sale as of December 31, 2014 . Deferred Rent Receivables, net Deferred rent receivables, net consisted of the following as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Deferred rent receivables $ 185,468 $ 158,405 Allowance for deferred rent receivables (2,116 ) (1,989 ) Deferred rent receivables, net $ 183,352 $ 156,416

Secured and Unsecured Debt of t

Secured and Unsecured Debt of the Operating Partnership	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 : Type of Debt Annual Stated Interest Rate (1) GAAP Effective Rate (1)(2) Maturity Date September 30, 2015 (3) December 31, 2014 (3) (in thousands) Mortgage note payable 4.27% 4.27% February 2018 $ 128,937 $ 130,767 Mortgage note payable (4) 4.48% 4.48% July 2027 96,743 97,000 Mortgage note payable (4) 6.05% 3.50% June 2019 86,737 89,242 Mortgage note payable 6.51% 6.51% February 2017 65,841 66,647 Mortgage note payable (4) (5) 5.23% 3.50% January 2016 51,431 52,793 Mortgage note payable (4) (5) 5.57% 3.25% February 2016 39,188 40,258 Mortgage note payable (6) 5.09% 3.50% August 2015 — 34,311 Mortgage note payable (6) 4.94% 4.00% April 2015 — 26,285 Mortgage note payable 7.15% 7.15% May 2017 4,649 6,568 Other Various Various Various 2,397 2,421 Total $ 475,923 $ 546,292 ________________________ (1) All interest rates presented are fixed-rate interest rates. (2) This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs. (3) Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014 , respectively. (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) These mortgage notes payable were repaid in October 2015 at par. (6) These mortgage notes payable were repaid during the nine months ended September 30, 2015 at par. 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. 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 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 will use the net proceeds to repay the 5.000% Unsecured Senior Notes upon maturity in November 2015 and 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 September 30, 2015 and December 31, 2014 : Principal Amount as of Issuance date Maturity date Stated coupon rate Effective interest rate (1) September 30, 2015 December 31, (in thousands) 4.375% Unsecured Senior Notes (2) September 2015 October 2025 4.375% 4.440% $ 400,000 $ — Unamortized discount $ (2,215 ) $ — Net carrying amount $ 397,785 $ — 4.250% Unsecured Senior Notes (3) July 2014 August 2029 4.250% 4.350% $ 400,000 $ 400,000 Unamortized discount (4,124 ) (4,348 ) Net carrying amount $ 395,876 $ 395,652 3.800% Unsecured Senior Notes (4) January 2013 January 2023 3.800% 3.804% $ 300,000 $ 300,000 Unamortized discount (72 ) (79 ) Net carrying amount $ 299,928 $ 299,921 4.800% Unsecured Senior Notes (4) (5) July 2011 July 2018 4.800% 4.827% $ 325,000 $ 325,000 Unamortized discount (209 ) (265 ) Net carrying amount $ 324,791 $ 324,735 6.625% Unsecured Senior Notes (6) May 2010 June 2020 6.625% 6.743% $ 250,000 $ 250,000 Unamortized discount (994 ) (1,154 ) Net carrying amount $ 249,006 $ 248,846 5.000% Unsecured Senior Notes (7) November 2010 November 2015 5.000% 5.014% $ 325,000 $ 325,000 Unamortized discount (4 ) (33 ) Net carrying amount $ 324,996 $ 324,967 ________________________ (1) This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of initial issuance discounts, excluding debt issuance 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. (7) Interest on these notes is payable semi-annually in arrears on May 3rd and November 3rd of each year. Unsecured Revolving Credit Facility and Term Loan Facility The following table summarizes the balance and terms of our unsecured revolving credit facility as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Outstanding borrowings $ — $ 140,000 Remaining borrowing capacity 600,000 460,000 Total borrowing capacity (1) $ 600,000 $ 600,000 Interest rate (2) — % 1.41 % Facility fee-annual rate (3) 0.200 % 0.250 % 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 term loan facility. (2) Our unsecured revolving credit facility interest rate was calculated based on an annual rate of LIBOR plus 1.050% and LIBOR plus 1.250% as of September 30, 2015 and December 31, 2014 , respectively. (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 September 30, 2015 , $4.9 million of deferred financing costs remains to be amortized through the maturity date of our unsecured revolving credit facility. 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 unsecured term loan facility as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Outstanding borrowings $ 150,000 $ 150,000 Interest rate (1) 1.35 % 1.56 % Maturity date July 2019 ________________________ (1) Our unsecured term loan facility interest rate was calculated based on an annual rate of LIBOR plus 1.150% and LIBOR plus 1.400% as of September 30, 2015 and December 31, 2014 , respectively. Additionally, the Company has a $39.0 million unsecured term loan outstanding with an annual interest rate of LIBOR plus 1.150% and LIBOR plus 1.400% as of September 30, 2015 and December 31, 2014 , respectively, that matures in July 2019. Debt Covenants and Restrictions The unsecured revolving credit facility, the unsecured term loan facility, the unsecured term loan, the unsecured senior 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 September 30, 2015 . Debt Maturities The following table summarizes the stated debt maturities and scheduled amortization payments, excluding debt discounts and premiums, as of September 30, 2015 : Year (in thousands) Remaining 2015 $ 327,768 2016 99,431 2017 71,748 2018 451,728 2019 265,370 Thereafter 1,441,643 Total (1) $ 2,657,688 ________________________ (1) Includes gross principal balance of outstanding debt before impact of net unamortized discounts totaling approximately $0.4 million . Capitalized Interest and Loan Fees The following table sets forth gross interest expense reported in continuing operations, including debt discount/premium and loan cost amortization, net of capitalized interest, for the three and nine months ended September 30, 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. Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Gross interest expense $ 27,386 $ 29,936 $ 82,322 $ 85,740 Capitalized interest and loan fees (14,567 ) (13,328 ) (37,761 ) (35,860 ) Interest expense $ 12,819 $ 16,608 $ 44,561 $ 49,880

Noncontrolling Interests on the

Noncontrolling Interests on the Company's Consolidated Financial Statements	9 Months Ended
	Sep. 30, 2015
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 an approximate 98.1% , 98.0% and 97.9% common general partnership interest in the Operating Partnership as of September 30, 2015 , December 31, 2014 and September 30, 2014 , respectively. The remaining approximate 1.9% , 2.0% and 2.1% common limited partnership interest as of September 30, 2015 , December 31, 2014 and September 30, 2014 , respectively, was owned by non-affiliate investors and certain of our executive officers and directors in the form of noncontrolling common units. There were 1,788,170 , 1,804,200 and 1,804,200 common units outstanding held by these investors, executive officers and directors as of September 30, 2015 , December 31, 2014 and September 30, 2014 , respectively. 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 $.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 $118.0 million and $126.8 million as of September 30, 2015 and December 31, 2014 , 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.

Stockholders' Equity of the Com

Stockholders' Equity of the Company	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Stockholders' Equity of the Company	Stockholders’ Equity of the Company At-The-Market Stock Offering Program 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 September 30, 2015 , we have sold 2,007,767 shares of common stock having an aggregate gross sales price of $150.1 million . As of September 30, 2015 , shares of common stock having an aggregate gross sales price of up to $149.9 million remain available to be sold under this program. No shares of common stock were sold under this program during the three months ended September 30, 2015 . 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 program for the nine months ended September 30, 2015 : Nine months ended September 30, 2015 (in millions, except share and per share data) Shares of common stock sold during the period 1,866,267 Weighted average price per common share $ 75.06 Aggregate gross proceeds $ 140.1 Aggregate net proceeds after sales agent compensation $ 138.2 Common Stock Issuance On July 1, 2015, the Company completed the sale of and issued 3,773,766 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.

Partners' Capital of the Operat

Partners' Capital of the Operating Partnership	9 Months Ended
	Sep. 30, 2015
Partners' Capital Notes [Abstract]
Common Units of the Operating Partnership	Partners’ Capital of the Operating Partnership 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-affiliate 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: September 30, 2015 December 31, 2014 September 30, 2014 Company owned common units in the Operating Partnership 92,220,367 86,259,684 83,388,220 Company owned general partnership interest 98.1 % 98.0 % 97.9 % Noncontrolling common units of the Operating Partnership 1,788,170 1,804,200 1,804,200 Ownership interest of noncontrolling interest 1.9 % 2.0 % 2.1 % For a further discussion of the noncontrolling common units as of September 30, 2015 and December 31, 2014 , refer to Note 7.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation Stockholder Approved Equity Compensation Plans As of September 30, 2015 , we maintained one share-based incentive compensation plan, the Kilroy Realty 2006 Incentive Award Plan, as amended (the “2006 Plan”). As of September 30, 2015 , 1,724,324 shares were available for grant under the 2006 Plan. The calculation of shares available for grant includes a reserve for a sufficient number of shares to cover the vesting and payment of performance-based vesting awards at the target levels for either performance and/or market conditions with outstanding performance periods. At our Annual Meeting of Stockholders held on May 21, 2015, stockholders approved an amendment and restatement of the 2006 Plan, which included an increase in the share limit to 8,320,000 shares. 2015 Share-Based Compensation Grants On January 27, 2015 , the Executive Compensation Committee of the Company’s Board of Directors awarded 212,468 restricted stock units (“RSUs”) to certain officers of the Company under the 2006 Plan, which included 127,657 RSUs (at the target level of performance), or 60% , that are subject to market and performance-based vesting requirements (the “2015 Performance-Based RSUs”) and 84,811 RSUs, or 40% , that are subject to time-based vesting requirements (the “2015 Time-Based RSUs”). 2015 Performance-Based RSU Grant The 2015 Performance-Based RSUs are scheduled to vest at the end of a three-year period based upon the achievement of pre-set FFO per share goals (the “performance condition”) for the year ending December 31, 2015 and also based upon the average annual relative total stockholder return ranking for the Company compared to an established comparison group of companies (the “market condition”) for the three-year period ending December 31, 2017. The 2015 Performance-Based RSUs are also subject to a three-year service vesting provision and are scheduled to cliff vest at the end of the three-year period. The number of 2015 Performance-Based RSUs ultimately earned could fluctuate from the target number of 2015 Performance-Based RSUs granted based upon the levels of achievement for both the performance condition and the market condition. The estimate of the number of 2015 Performance-Based RSUs earned are evaluated quarterly during the 2015 performance period based on our estimate as to the 2015 FFO per share performance measured against the applicable goals. As of September 30, 2015 , 168,788 2015 Performance-Based RSUs are estimated to be earned based on the Company’s estimate of 2015 FFO per share performance measured against the applicable goals, and the compensation cost recorded to date for this program was based on that revised estimate. Compensation expense for the 2015 Performance-Based RSU grant will be recorded on a straight-line basis over the three-year period. Each 2015 Performance-Based RSU represents the right to receive one share of our common stock in the future. The total fair value of the 2015 Performance-Based RSU grant was $10.1 million at January 27, 2015 and 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 2015 Performance-Based RSU grant takes into consideration the likelihood of achievement of both the performance condition and the market condition discussed above. For the nine months ended September 30, 2015 , we recorded compensation expense based upon the $78.55 fair value at January 27, 2015 . The following table summarizes the assumptions utilized in the Monte Carlo simulation pricing model: Fair Value Assumptions Fair value per share at January 27, 2015 $78.55 Expected share price volatility 20.00% Risk-free interest rate 0.92% Remaining expected life 2.9 years The computation of expected volatility is based on a blend of the historical volatility of our shares of common stock over approximately six years, as that is expected to be most consistent with future volatility and equates to a time period twice as long as the approximate three-year remaining performance period of the RSUs 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 January 27, 2015 . The expected dividend yield is estimated by examining the average of the historical dividend yield levels over the remaining 2.9 year term of the RSUs and our current annualized dividend yield as of January 27, 2015 . The expected life of the RSUs is equal to the remaining 2.9 year vesting period at January 27, 2015 . 2015 Time-Based RSU Grant The 2015 Time-Based RSUs are scheduled to vest in three equal installments beginning on January 5, 2016 through January 5, 2018. Compensation expense for the 2015 Time-Based RSUs will be recognized on a straight-line basis over the three-year service vesting period. Each 2015 Time-Based RSU represents the right to receive one share of our common stock in the future. The total fair value of the 2015 Time-Based RSU grant was $6.4 million , which was based on the $75.34 closing share price of the Company’s common stock on the NYSE on January 27, 2015 . Share-Based Award Activity During the nine months ended September 30, 2015 , 265,000 non-qualified stock options were exercised and issued at an exercise price per share equal to $42.61 . As of September 30, 2015 , we had 687,000 stock options outstanding. Share-Based Compensation Cost Recorded During the Period The total compensation cost for all share-based compensation programs was $4.3 million and $4.0 million for the three months ended September 30, 2015 and 2014 , respectively, and $13.6 million and $10.3 million for the nine months ended September 30, 2015 and 2014 , respectively. Of the total share-based compensation costs, $0.7 million and $0.6 million was capitalized as part of real estate assets for the three months ended September 30, 2015 and 2014 , respectively, and $2.3 million and $1.5 million was capitalized as part of real estate assets for the nine months ended September 30, 2015 and 2014 , respectively. As of September 30, 2015 , there was approximately $35.2 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 2.1 years. The remaining compensation cost related to these nonvested incentive awards had been recognized in periods prior to September 30, 2015 .

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies General As of September 30, 2015 , we had commitments of approximately $481.2 million , excluding our ground lease commitments, for contracts and executed leases directly related to our operating and redevelopment properties. 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 September 30, 2015 , we had accrued environmental remediation liabilities of approximately $19.4 million recorded on our consolidated balance sheets in connection with certain of our recent development acquisitions and related development activities. It is possible that we could incur additional environmental remediation costs in connection with these recent development acquisitions. However, given we are in the very early stages of development, possible additional environmental costs are not reasonably estimable at this time.

Fair Value Measurements and Dis

Fair Value Measurements and Disclosures	9 Months Ended
	Sep. 30, 2015
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. The following table sets forth the fair value of our marketable securities as of September 30, 2015 and December 31, 2014 : Fair Value (Level 1) (1) September 30, 2015 December 31, 2014 Description (in thousands) Marketable securities (2) $ 12,638 $ 11,971 ________________________ (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 gain 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 (loss) gain on marketable securities recorded during the three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Description (in thousands) (in thousands) Net (loss) gain on marketable securities $ (681 ) $ (39 ) $ (171 ) $ 507 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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 Carrying Fair Carrying Fair (in thousands) Liabilities Secured debt (1) $ 475,923 $ 487,563 $ 546,292 $ 559,483 Unsecured debt, net (2) 2,181,382 2,228,225 1,783,121 1,858,492 Unsecured line of credit (1) (3) — — 140,000 145,051 ________________________ (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. (2) Fair value calculated using Level I and Level II inputs. Level I inputs are based on quoted prices for identical instruments in active markets. The carrying value and fair value of the Level I instruments was $2.0 billion and $2.0 billion , respectively, as of September 30, 2015 . The carrying value and fair value of the Level I instruments as of December 31, 2014 , was $1.3 billion and $1.3 billion , respectively. The carrying value and fair value of the Level II instruments was $189.0 million and $189.0 million , respectively, as of September 30, 2015 . The carrying value and fair value of the Level II instruments as of December 31, 2014 , was $513.7 million and $536.3 million , respectively. (3) There was no outstanding balance on the unsecured line of credit as of September 30, 2015 .

Net Income Available to Common

Net Income Available to Common Stockholders Per Share of the Company	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Net Income (Loss) 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 three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except share and per share amounts) Numerator: Income from continuing operations $ 106,704 $ 13,168 $ 209,296 $ 39,896 Income from continuing operations attributable to noncontrolling common units of the Operating Partnership (1,945 ) (193 ) (3,850 ) (635 ) Preferred dividends (3,313 ) (3,313 ) (9,938 ) (9,938 ) Allocation to participating securities (1) (367 ) (432 ) (1,200 ) (1,285 ) Numerator for basic and diluted income from continuing operations available to common stockholders 101,079 9,230 194,308 28,038 Income from discontinued operations (2) — 6,135 — 112,482 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — (128 ) — (2,376 ) Numerator for basic and diluted net income available to common stockholders $ 101,079 $ 15,237 $ 194,308 $ 138,144 Denominator: Basic weighted average vested shares outstanding 92,150,341 83,161,323 89,077,012 82,525,033 Effect of dilutive securities 488,724 1,949,133 516,249 2,097,589 Diluted weighted average vested shares and common share equivalents outstanding 92,639,065 85,110,456 89,593,261 84,622,622 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 1.10 $ 0.11 $ 2.18 $ 0.34 Income from discontinued operations per common share (2) — 0.07 — 1.33 Net income available to common stockholders per share $ 1.10 $ 0.18 $ 2.18 $ 1.67 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 1.09 $ 0.11 $ 2.17 $ 0.33 Income from discontinued operations per common share (2) — 0.07 — 1.30 Net income available to common stockholders per share $ 1.09 $ 0.18 $ 2.17 $ 1.63 ________________________ (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 1). 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 shares, including stock options, RSUs and other securities are considered in our diluted earnings per share calculation for the three and nine months ended September 30, 2015 and 2014 , because we reported income from continuing operations attributable to common stockholders in the respective periods and the effect was dilutive. Certain market measure-based RSUs are not included in dilutive securities for the three and nine months ended September 30, 2015 and 2014 as not all performance metrics had been met by the end of the applicable reporting periods. See Note 10 “Share-Based Compensation” for additional information regarding stock options and other share-based compensation.

Net Income Available to Commo29

Net Income Available to Common Unitholders Per Unit of the Operating Partnership	9 Months Ended
	Sep. 30, 2015
Earnings Per Unit [Abstract]
Net Income (Loss) 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 three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 106,704 $ 13,168 $ 209,296 $ 39,896 Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries (64 ) (59 ) (211 ) (188 ) Preferred distributions (3,313 ) (3,313 ) (9,938 ) (9,938 ) Allocation to participating securities (1) (367 ) (432 ) (1,200 ) (1,285 ) Numerator for basic and diluted income from continuing operations available to common unitholders 102,960 9,364 197,947 28,485 Income from discontinued operations (2) — 6,135 — 112,482 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — — — (13 ) Numerator for basic and diluted net income available to common unitholders $ 102,960 $ 15,499 $ 197,947 $ 140,954 Denominator: Basic weighted average vested units outstanding 93,938,783 84,965,523 90,869,696 84,329,317 Effect of dilutive securities 488,724 1,949,133 516,249 2,097,589 Diluted weighted average vested units and common unit equivalents outstanding 94,427,507 86,914,656 91,385,945 86,426,906 Basic earnings per unit: Income from continuing operations available to common unitholders per unit $ 1.10 $ 0.11 $ 2.18 $ 0.34 Income from discontinued operations per common unit (2) — 0.07 — 1.33 Net income available to common unitholders per unit $ 1.10 $ 0.18 $ 2.18 $ 1.67 Diluted earnings per unit: Income from continuing operations available to common unitholders per unit $ 1.09 $ 0.11 $ 2.17 $ 0.33 Income from discontinued operations per common unit (2) — 0.07 — 1.30 Net income available to common unitholders per unit $ 1.09 $ 0.18 $ 2.17 $ 1.63 ________________________ (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 1). 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 three and nine months ended September 30, 2015 and 2014 , because we reported income from continuing operations attributable to common unitholders in the respective periods and the effect was dilutive. Certain market measure-based RSUs are not included in dilutive securities for the three and nine months ended September 30, 2015 and 2014 as not all performance metrics had been met by the end of the applicable reporting periods. See Note 10 “Share-Based Compensation” for additional information regarding stock options and other share-based compensation.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 14, 2015 , aggregate dividends, distributions and dividend equivalents of $33.3 million were paid to common stockholders and common unitholders of record on September 30, 2015 and RSU holders of record on the payment date. On October 9 and 22, 2015, the Company repaid two secured mortgages at par totaling approximately $90.1 million .

Organization and Basis of Pre31

Organization and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation Policy	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, 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, 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.
Basis of Accounting	The accompanying interim financial statements have been prepared by management in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and in conjunction with the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures required for annual financial statements have been condensed or excluded pursuant to SEC rules and regulations. Accordingly, the interim financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the accompanying interim financial statements reflect all adjustments of a normal and recurring nature that are considered necessary for a fair presentation of the results for the interim periods presented. However, the results of operations for the interim periods are not necessarily indicative of the results that may be expected for the year ending December 31, 2015. The interim financial statements for the Company and the Operating Partnership should be read in conjunction with the audited consolidated financial statements and notes thereto included in our annual report on Form 10-K for the year ended December 31, 2014 . Certain amounts in the consolidated statements of operations for prior periods have been reclassified to reflect the activity of discontinued operations disposed of prior to the Company's adoption of Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-08 (“ASU 2014-08”). Properties classified as held for sale and/or disposed of prior to January 1, 2015 are presented as discontinued operations for all periods presented.
Partially Owned Entities and Variable Interest Entities	At September 30, 2015 , the consolidated financial statements of the Company and the Operating Partnership included one variable interest entity (“VIE”), in which we were deemed to be the primary beneficiary. The VIE, Redwood LLC, was established in the second quarter of 2013 in connection with an undeveloped land acquisition. The impact of consolidating the VIE increased the Company’s total assets, liabilities and noncontrolling interests by approximately $180.7 million (of which $176.9 million related to real estate held for investment on our consolidated balance sheet), approximately $43.5 million and approximately $6.3 million , respectively, as of September 30, 2015 . As of December 31, 2014 , 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 of the VIEs was Redwood LLC and the remaining VIE was established during the fourth quarter of 2014 to facilitate potential Section 1031 Exchanges. During the three months ended March 31, 2015, the Section 1031 Exchange was successfully completed and the VIE was terminated. As a result, $59.2 million of our restricted cash balance at December 31, 2014 , which related to prior period disposition proceeds that were set aside to facilitate the Section 1031 Exchange, was released from escrow. The impact of consolidating the VIEs increased the Company’s total assets, liabilities and noncontrolling interests by approximately $219.6 million (of which $211.8 million related to real estate held for investment on our consolidated balance sheet), approximately $23.4 million and approximately $5.9 million , respectively, as of December 31, 2014 .
Recent Accounting Pronouncements	Recently Issued Accounting Pronouncements On August 12, 2015, the FASB issued ASU No. 2015-14 (“ASU 2015-14”) to defer the effective date 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 assessing the impact of the guidance on our consolidated financial statements and notes to our consolidated financial statements. On April 7, 2015, the FASB issued ASU No. 2015-03 (“ASU 2015-03”) to amend the accounting guidance for the presentation of debt issuance costs. The standard requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. On August 18, 2015, the FASB also issued ASU No. 2015-15 (“ASU 2015-15”) to address the presentation of debt issuance costs specifically related to line-of-credit arrangements. The standard clarifies that an entity 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 an outstanding borrowings on the line-of credit arrangement. ASU 2015-03 and ASU 2015-15 are effective for public business entities for fiscal years beginning after December 15, 2015 and retrospective application is required. Early adoption of the guidance is permitted. The Company expects to adopt the guidance effective January 1, 2016 and the guidance will not have any impact on our consolidated statements of operations, equity/capital, or cash flows. In February 2015, the FASB issued an update (“ASU 2015-02”) Amendments to the Consolidation Analysis to ASC Topic 810, Consolidation . ASU 2015-02 affects reporting entities that are required to evaluate whether they should 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 consolidated analysis of reporting entities that are involved with VIEs, and (iv) provide a scope exception for certain entities. ASU 2015-02 is effective for interim and annual reporting periods beginning after December 15, 2015. The Company is currently assessing the impact of the guidance on our consolidated financial statements and notes to our consolidated financial statements.

Organization and Basis of Pre32

Organization and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of real estate properties	Our stabilized portfolio of operating properties was comprised of the following office properties at September 30, 2015 : Number of Buildings Rentable Square Feet Number of Tenants Percentage Occupied Stabilized Office Properties 101 13,050,947 509 95.6 % As of September 30, 2015 , the following properties were excluded from our stabilized portfolio: Number of Properties/Projects Estimated Rentable Square Feet Development projects in “ lease-up ” 1 108,539 Development projects under construction (1) 7 2,322,000 ________________________ (1) Estimated rentable square feet upon completion.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Schedule of Significant Acquisitions	Development Project Acquisitions During the nine months ended September 30, 2015 , we acquired the development opportunities listed below from unrelated third parties. The acquisitions were funded with proceeds from various sources, including the Company’s unsecured revolving credit facility, at-the-market stock offering program (see Note 8) and prior year disposition proceeds. As of September 30, 2015 , the underlying assets were included as undeveloped land and construction in progress in our consolidated balance sheets. Project Date of Acquisition City/Submarket Type Purchase Price (in millions) 333 Dexter (1) February 13, 2015 South Lake Union, WA Land $ 49.5 100 Hooper (2) July 7, 2015 San Francisco, CA Land 78.0 Total Acquisitions $ 127.5 ________________________ (1) 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. (2) 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. The Company expects to develop and own two buildings on the site encompassing office and production design and repair space totaling approximately 400,000 square feet.

Dispositions (Tables)

Dispositions (Tables)	9 Months Ended
	Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Disclosure of Long Lived Assets Held-for-sale [Table Text Block]	The following table summarizes the operating properties sold during the nine months ended September 30, 2015 : Location Property Type Month of Disposition Number of Buildings Rentable Square Feet 15050 NE 36th Street, Redmond, WA Office April 1 122,103 San Diego Properties - Tranche 1 (1) Office April 3 384,468 San Diego Properties - Tranche 2 (2) Office July 6 539,823 Total Dispositions 10 1,046,394 ________________________ (1) The San Diego Properties - Tranche 1 include the following: 10770 Wateridge Circle, 6200 Greenwich Drive, and 6220 Greenwich Drive. (2) The San Diego Properties - Tranche 2 include the following: 6260 Sequence Drive, 6290 Sequence, Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive, and 4921 Directors Place.

Deferred Leasing Costs and Ac35

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Tables)	9 Months Ended
	Sep. 30, 2015
Intangible Assets and Liabilities Disclosure [Abstract]
Summary of identified deferred leasing costs and acquisition-related intangible assets and liabilities	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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Deferred Leasing Costs and Acquisition-Related Intangible Assets, net: Deferred leasing costs $ 201,605 $ 216,102 Accumulated amortization (74,997 ) (74,904 ) Deferred leasing costs, net 126,608 141,198 Above-market operating leases 11,026 20,734 Accumulated amortization (6,380 ) (13,952 ) Above-market operating leases, net 4,646 6,782 In-place leases 74,071 97,250 Accumulated amortization (32,331 ) (43,773 ) In-place leases, net 41,740 53,477 Below-market ground lease obligation 490 490 Accumulated amortization (27 ) (21 ) Below-market ground lease obligation, net 463 469 Total deferred leasing costs and acquisition-related intangible assets, net $ 173,457 $ 201,926 Acquisition-Related Intangible Liabilities, net: (1) Below-market operating leases $ 55,136 $ 68,051 Accumulated amortization (26,632 ) (30,620 ) Below-market operating leases, net 28,504 37,431 Above-market ground lease obligation 6,320 6,320 Accumulated amortization (399 ) (324 ) Above-market ground lease obligation, net 5,921 5,996 Total acquisition-related intangible liabilities, net $ 34,425 $ 43,427 ________________________ (1) Included in deferred revenue and acquisition-related intangible liabilities, net in the consolidated balance sheets.
Schedule Of Finite Lived Intangible Assets and Liabilities Amortization Expense	The following table sets forth amortization related to deferred leasing costs and acquisition-related intangibles for the three and nine months ended September 30, 2015 and 2014 , including amounts attributable to discontinued operations for 2014: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Deferred leasing costs (1) $ 6,932 $ 7,132 $ 20,847 $ 20,683 Above-market operating leases (2) 487 1,305 2,135 4,230 In-place leases (1) 3,073 5,169 11,710 17,090 Below-market ground lease obligation (3) 2 2 6 6 Below-market operating leases (4) (2,228 ) (2,940 ) (8,905 ) (10,054 ) Above-market ground lease obligation (5) (26 ) (26 ) (76 ) (76 ) Total $ 8,240 $ 10,642 $ 25,717 $ 31,879 ________________________ (1) The amortization of deferred leasing costs related to lease incentives is recorded to rental income and other deferred leasing costs and in-place leases is recorded to depreciation and amortization expense 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.
Schedule of Finite Lived Intangible Assets And Liabilities Future Amortization Expense	The following table sets forth the estimated annual amortization expense related to deferred leasing costs and acquisition-related intangibles as of September 30, 2015 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) Remaining 2015 $ 6,740 $ 399 $ 2,800 $ 2 $ (2,044 ) $ (25 ) 2016 25,662 1,499 10,449 8 (7,638 ) (101 ) 2017 22,661 1,241 9,113 8 (7,017 ) (101 ) 2018 19,023 831 6,373 8 (5,735 ) (101 ) 2019 15,150 643 4,714 8 (3,597 ) (101 ) Thereafter 37,372 33 8,291 429 (2,473 ) (5,492 ) Total $ 126,608 $ 4,646 $ 41,740 $ 463 $ (28,504 ) $ (5,921 ) ________________________ (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)	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (1) (in thousands) Current receivables $ 13,372 $ 9,228 Allowance for uncollectible tenant receivables (1,839 ) (1,999 ) Current receivables, net $ 11,533 $ 7,229
Deferred Rent Receivables, net	Deferred rent receivables, net consisted of the following as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Deferred rent receivables $ 185,468 $ 158,405 Allowance for deferred rent receivables (2,116 ) (1,989 ) Deferred rent receivables, net $ 183,352 $ 156,416

Secured and Unsecured Debt of37

Secured and Unsecured Debt of the Operating Partnership (Tables) - Kilroy Realty, L.P. [Member]	9 Months Ended
	Sep. 30, 2015
Debt Instrument [Line Items]
Schedule of Term Loan Facilities [Table Text Block]	The following table summarizes the balance and terms of our unsecured term loan facility as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Outstanding borrowings $ 150,000 $ 150,000 Interest rate (1) 1.35 % 1.56 % Maturity date July 2019
Unsecured Revolving Credit Facility	The following table summarizes the balance and terms of our unsecured revolving credit facility as of September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 (in thousands) Outstanding borrowings $ — $ 140,000 Remaining borrowing capacity 600,000 460,000 Total borrowing capacity (1) $ 600,000 $ 600,000 Interest rate (2) — % 1.41 % Facility fee-annual rate (3) 0.200 % 0.250 % 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 term loan facility. (2) Our unsecured revolving credit facility interest rate was calculated based on an annual rate of LIBOR plus 1.050% and LIBOR plus 1.250% as of September 30, 2015 and December 31, 2014 , respectively. (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 September 30, 2015 , $4.9 million of deferred financing costs remains to be amortized through the maturity date of our unsecured revolving credit facility.
Stated debt maturities and scheduled amortization payments, excluding debt discounts	The following table summarizes the stated debt maturities and scheduled amortization payments, excluding debt discounts and premiums, as of September 30, 2015 : Year (in thousands) Remaining 2015 $ 327,768 2016 99,431 2017 71,748 2018 451,728 2019 265,370 Thereafter 1,441,643 Total (1) $ 2,657,688 ________________________ (1) Includes gross principal balance of outstanding debt before impact of net unamortized discounts totaling approximately $0.4 million
Capitalized interest and loan fees	The following table sets forth gross interest expense reported in continuing operations, including debt discount/premium and loan cost amortization, net of capitalized interest, for the three and nine months ended September 30, 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. Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Gross interest expense $ 27,386 $ 29,936 $ 82,322 $ 85,740 Capitalized interest and loan fees (14,567 ) (13,328 ) (37,761 ) (35,860 ) Interest expense $ 12,819 $ 16,608 $ 44,561 $ 49,880
Secured Debt [Member]
Debt Instrument [Line Items]
Balance and significant terms of debt	The following table sets forth the composition of our secured debt as of September 30, 2015 and December 31, 2014 : Type of Debt Annual Stated Interest Rate (1) GAAP Effective Rate (1)(2) Maturity Date September 30, 2015 (3) December 31, 2014 (3) (in thousands) Mortgage note payable 4.27% 4.27% February 2018 $ 128,937 $ 130,767 Mortgage note payable (4) 4.48% 4.48% July 2027 96,743 97,000 Mortgage note payable (4) 6.05% 3.50% June 2019 86,737 89,242 Mortgage note payable 6.51% 6.51% February 2017 65,841 66,647 Mortgage note payable (4) (5) 5.23% 3.50% January 2016 51,431 52,793 Mortgage note payable (4) (5) 5.57% 3.25% February 2016 39,188 40,258 Mortgage note payable (6) 5.09% 3.50% August 2015 — 34,311 Mortgage note payable (6) 4.94% 4.00% April 2015 — 26,285 Mortgage note payable 7.15% 7.15% May 2017 4,649 6,568 Other Various Various Various 2,397 2,421 Total $ 475,923 $ 546,292 ________________________ (1) All interest rates presented are fixed-rate interest rates. (2) This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs. (3) Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014 , respectively. (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) These mortgage notes payable were repaid in October 2015 at par. (6) These mortgage notes payable were repaid during the nine months ended September 30, 2015 at par.
Senior Notes [Member]
Debt Instrument [Line Items]
Balance and significant terms of debt	The following table summarizes the balance and significant terms of the registered unsecured senior notes issued by the Operating Partnership as of September 30, 2015 and December 31, 2014 : Principal Amount as of Issuance date Maturity date Stated coupon rate Effective interest rate (1) September 30, 2015 December 31, (in thousands) 4.375% Unsecured Senior Notes (2) September 2015 October 2025 4.375% 4.440% $ 400,000 $ — Unamortized discount $ (2,215 ) $ — Net carrying amount $ 397,785 $ — 4.250% Unsecured Senior Notes (3) July 2014 August 2029 4.250% 4.350% $ 400,000 $ 400,000 Unamortized discount (4,124 ) (4,348 ) Net carrying amount $ 395,876 $ 395,652 3.800% Unsecured Senior Notes (4) January 2013 January 2023 3.800% 3.804% $ 300,000 $ 300,000 Unamortized discount (72 ) (79 ) Net carrying amount $ 299,928 $ 299,921 4.800% Unsecured Senior Notes (4) (5) July 2011 July 2018 4.800% 4.827% $ 325,000 $ 325,000 Unamortized discount (209 ) (265 ) Net carrying amount $ 324,791 $ 324,735 6.625% Unsecured Senior Notes (6) May 2010 June 2020 6.625% 6.743% $ 250,000 $ 250,000 Unamortized discount (994 ) (1,154 ) Net carrying amount $ 249,006 $ 248,846 5.000% Unsecured Senior Notes (7) November 2010 November 2015 5.000% 5.014% $ 325,000 $ 325,000 Unamortized discount (4 ) (33 ) Net carrying amount $ 324,996 $ 324,967 ________________________ (1) This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of initial issuance discounts, excluding debt issuance 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. (7) Interest on these notes is payable semi-annually in arrears on May 3rd and November 3rd of each year.

Stockholders' Equity of the C38

Stockholders' Equity of the Company (Tables)	9 Months Ended
	Sep. 30, 2015
Class of Stock [Line Items]
Schedule of Stockholders Equity [Table Text Block]	The following table sets forth information regarding sales of our common stock under our at-the-market offering program for the nine months ended September 30, 2015 : Nine months ended September 30, 2015 (in millions, except share and per share data) Shares of common stock sold during the period 1,866,267 Weighted average price per common share $ 75.06 Aggregate gross proceeds $ 140.1 Aggregate net proceeds after sales agent compensation $ 138.2

Partners' Capital of the Oper39

Partners' Capital of the Operating Partnership Ownership Interest (Tables)	9 Months Ended
	Sep. 30, 2015
Noncontrolling Interest [Abstract]
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-affiliate 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: September 30, 2015 December 31, 2014 September 30, 2014 Company owned common units in the Operating Partnership 92,220,367 86,259,684 83,388,220 Company owned general partnership interest 98.1 % 98.0 % 97.9 % Noncontrolling common units of the Operating Partnership 1,788,170 1,804,200 1,804,200 Ownership interest of noncontrolling interest 1.9 % 2.0 % 2.1 %

Share-Based Compensation Share-

Share-Based Compensation Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Restricted Stock Units, Valuation Assumptions	The following table summarizes the assumptions utilized in the Monte Carlo simulation pricing model: Fair Value Assumptions Fair value per share at January 27, 2015 $78.55 Expected share price volatility 20.00% Risk-free interest rate 0.92% Remaining expected life 2.9 years

Fair Value Measurements and D41

Fair Value Measurements and Disclosures (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 : Fair Value (Level 1) (1) September 30, 2015 December 31, 2014 Description (in thousands) Marketable securities (2) $ 12,638 $ 11,971 ________________________ (1) Based on quoted prices in active markets for identical securities. (2) The marketable securities are held in a limited rabbi trust.
Fair value adjustment of marketable securities and deferred compensation plan liability	The following table sets forth the net (loss) gain on marketable securities recorded during the three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Description (in thousands) (in thousands) Net (loss) gain on marketable securities $ (681 ) $ (39 ) $ (171 ) $ 507
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 September 30, 2015 and December 31, 2014 : September 30, 2015 December 31, 2014 Carrying Fair Carrying Fair (in thousands) Liabilities Secured debt (1) $ 475,923 $ 487,563 $ 546,292 $ 559,483 Unsecured debt, net (2) 2,181,382 2,228,225 1,783,121 1,858,492 Unsecured line of credit (1) (3) — — 140,000 145,051 ________________________ (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. (2) Fair value calculated using Level I and Level II inputs. Level I inputs are based on quoted prices for identical instruments in active markets. The carrying value and fair value of the Level I instruments was $2.0 billion and $2.0 billion , respectively, as of September 30, 2015 . The carrying value and fair value of the Level I instruments as of December 31, 2014 , was $1.3 billion and $1.3 billion , respectively. The carrying value and fair value of the Level II instruments was $189.0 million and $189.0 million , respectively, as of September 30, 2015 . The carrying value and fair value of the Level II instruments as of December 31, 2014 , was $513.7 million and $536.3 million , respectively. (3) There was no outstanding balance on the unsecured line of credit as of September 30, 2015 .

Net Income Available to Commo42

Net Income Available to Common Stockholders Per Share of the Company (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Net income (loss) 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 three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except share and per share amounts) Numerator: Income from continuing operations $ 106,704 $ 13,168 $ 209,296 $ 39,896 Income from continuing operations attributable to noncontrolling common units of the Operating Partnership (1,945 ) (193 ) (3,850 ) (635 ) Preferred dividends (3,313 ) (3,313 ) (9,938 ) (9,938 ) Allocation to participating securities (1) (367 ) (432 ) (1,200 ) (1,285 ) Numerator for basic and diluted income from continuing operations available to common stockholders 101,079 9,230 194,308 28,038 Income from discontinued operations (2) — 6,135 — 112,482 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — (128 ) — (2,376 ) Numerator for basic and diluted net income available to common stockholders $ 101,079 $ 15,237 $ 194,308 $ 138,144 Denominator: Basic weighted average vested shares outstanding 92,150,341 83,161,323 89,077,012 82,525,033 Effect of dilutive securities 488,724 1,949,133 516,249 2,097,589 Diluted weighted average vested shares and common share equivalents outstanding 92,639,065 85,110,456 89,593,261 84,622,622 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 1.10 $ 0.11 $ 2.18 $ 0.34 Income from discontinued operations per common share (2) — 0.07 — 1.33 Net income available to common stockholders per share $ 1.10 $ 0.18 $ 2.18 $ 1.67 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 1.09 $ 0.11 $ 2.17 $ 0.33 Income from discontinued operations per common share (2) — 0.07 — 1.30 Net income available to common stockholders per share $ 1.09 $ 0.18 $ 2.17 $ 1.63 ________________________ (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 1). 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 Commo43

Net Income Available to Common Unitholders Per Unit of the Operating Partnership (Tables)	9 Months Ended
	Sep. 30, 2015
Net Income Available To Common Unitholders [Line Items]
Net income (loss) 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 three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except share and per share amounts) Numerator: Income from continuing operations $ 106,704 $ 13,168 $ 209,296 $ 39,896 Income from continuing operations attributable to noncontrolling common units of the Operating Partnership (1,945 ) (193 ) (3,850 ) (635 ) Preferred dividends (3,313 ) (3,313 ) (9,938 ) (9,938 ) Allocation to participating securities (1) (367 ) (432 ) (1,200 ) (1,285 ) Numerator for basic and diluted income from continuing operations available to common stockholders 101,079 9,230 194,308 28,038 Income from discontinued operations (2) — 6,135 — 112,482 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — (128 ) — (2,376 ) Numerator for basic and diluted net income available to common stockholders $ 101,079 $ 15,237 $ 194,308 $ 138,144 Denominator: Basic weighted average vested shares outstanding 92,150,341 83,161,323 89,077,012 82,525,033 Effect of dilutive securities 488,724 1,949,133 516,249 2,097,589 Diluted weighted average vested shares and common share equivalents outstanding 92,639,065 85,110,456 89,593,261 84,622,622 Basic earnings per share: Income from continuing operations available to common stockholders per share $ 1.10 $ 0.11 $ 2.18 $ 0.34 Income from discontinued operations per common share (2) — 0.07 — 1.33 Net income available to common stockholders per share $ 1.10 $ 0.18 $ 2.18 $ 1.67 Diluted earnings per share: Income from continuing operations available to common stockholders per share $ 1.09 $ 0.11 $ 2.17 $ 0.33 Income from discontinued operations per common share (2) — 0.07 — 1.30 Net income available to common stockholders per share $ 1.09 $ 0.18 $ 2.17 $ 1.63 ________________________ (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 1). 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 (loss) 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 three and nine months ended September 30, 2015 and 2014 : Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except unit and per unit amounts) Numerator: Income from continuing operations $ 106,704 $ 13,168 $ 209,296 $ 39,896 Income from continuing operations attributable to noncontrolling interests in consolidated subsidiaries (64 ) (59 ) (211 ) (188 ) Preferred distributions (3,313 ) (3,313 ) (9,938 ) (9,938 ) Allocation to participating securities (1) (367 ) (432 ) (1,200 ) (1,285 ) Numerator for basic and diluted income from continuing operations available to common unitholders 102,960 9,364 197,947 28,485 Income from discontinued operations (2) — 6,135 — 112,482 Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership (2) — — — (13 ) Numerator for basic and diluted net income available to common unitholders $ 102,960 $ 15,499 $ 197,947 $ 140,954 Denominator: Basic weighted average vested units outstanding 93,938,783 84,965,523 90,869,696 84,329,317 Effect of dilutive securities 488,724 1,949,133 516,249 2,097,589 Diluted weighted average vested units and common unit equivalents outstanding 94,427,507 86,914,656 91,385,945 86,426,906 Basic earnings per unit: Income from continuing operations available to common unitholders per unit $ 1.10 $ 0.11 $ 2.18 $ 0.34 Income from discontinued operations per common unit (2) — 0.07 — 1.33 Net income available to common unitholders per unit $ 1.10 $ 0.18 $ 2.18 $ 1.67 Diluted earnings per unit: Income from continuing operations available to common unitholders per unit $ 1.09 $ 0.11 $ 2.17 $ 0.33 Income from discontinued operations per common unit (2) — 0.07 — 1.30 Net income available to common unitholders per unit $ 1.09 $ 0.18 $ 2.17 $ 1.63 ________________________ (1) Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs.

Organization and Basis of Pre44

Organization and Basis of Presentation (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)ft²projecttenantbuildingproperty
Real Estate Properties [Line Items]
Number of buildings | building	10
Rentable square feet	1,046,394
Dispositions Sales Price | $	$ 309.2
Kilroy Realty Finance, Inc. [Member]
Real Estate Properties [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	1.00%
Lease Up Properties [Member]
Real Estate Properties [Line Items]
Number of buildings | project	1
Rentable square feet	108,539
Development Properties [Member]
Real Estate Properties [Line Items]
Number of buildings | project	7	[1]
Rentable square feet	2,322,000	[1]
Office Properties [Member]
Real Estate Properties [Line Items]
Number of buildings | building	101
Rentable square feet	13,050,947
Number of Tenants | tenant	509
Percentage Occupied	95.60%
WASHINGTON
Real Estate Properties [Line Items]
Number of buildings | property	12
Development Properties [Domain]
Real Estate Properties [Line Items]
Number of buildings | project	10
[1]	Estimated rentable square feet upon completion.

Organization and Basis of Pre45

Organization and Basis of Presentation (Details Textuals) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2014USD ($)	Sep. 30, 2015USD ($)abuildingproperty	Sep. 30, 2014USD ($)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Lease-Up Properties, Maximum Stabilized Occupacy, Percentage		95.00%
Number of buildings | building		10
Percentage of general partnership interest owned by the company in the Operating Partnership	98.00%	98.10%	97.90%
Percentage of Common limited partnership interest owned by certain non-affiliated investors and certain directors and officers of the Company in the Operating Partnership	2.00%	1.90%	2.10%
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 219,600	$ 180,700
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	23,400	43,500
Noncontrolling Interest in Variable Interest Entity	5,862	6,336
Proceeds from Sale of Real Estate Held-for-investment		$ 319,639	$ 368,381
Number of Real Estate Properties Sold | property		10
WASHINGTON
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of buildings | property		12
Kilroy Realty, L.P. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of limited partnership interest owned by Operating Partnership		99.00%
Proceeds from Sale of Real Estate Held-for-investment		$ 319,639	$ 368,381
Kilroy Realty Finance, Inc. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		1.00%
Real Estate Investment [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	211,800	$ 176,900
Restricted cash [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Proceeds from Sale of Real Estate Held-for-investment	$ 59,200
Land [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Area of Land | a		106

Acquisitions (Details)

Acquisitions (Details) $ in Thousands		9 Months Ended
		Sep. 30, 2015USD ($)ft²building	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Payments to Acquire Land		$ 127,500
Number of buildings | building		10
Rentable square feet | ft²		1,046,394
Liabilities
Accounts Payable and Accrued Liabilities		$ 249,980	$ 225,830
Dexter Project [Member] [Member]
Business Acquisition [Line Items]
Accrued Liabilities and Acquisition Costs	[1],[2]	2,400
Payments to Acquire Land	[1]	49,500
Hooper Project [Member] [Member] [Domain]
Business Acquisition [Line Items]
Accrued Liabilities and Acquisition Costs		4,100
Payments to Acquire Land	[2]	$ 78,000
[1]	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.
[2]	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. The Company expects to develop and own two buildings on the site encompassing office and production design and repair space totaling approximately 400,000 square feet.

Dispositions (Details)

Dispositions (Details) $ in Thousands		Jan. 15, 2015USD ($)	Sep. 30, 2015USD ($)ft²building	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)ft²building	Sep. 30, 2014USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings			10		10
Net Rentable Area | ft²			1,046,394		1,046,394
Dispositions Sales Price | $					$ 309,200
Gains on sales of depreciable operating properties | $			$ 78,522	$ 0	109,950	$ 0
Gain on sale of land | $			$ 0	$ 0	$ 17,268	$ 3,490
15050 NE 36th Street, Redmond, WA [Domain]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings			1		1
Net Rentable Area | ft²			122,103		122,103
San Diego Properties Phase I [Domain]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings	[1]		3		3
Net Rentable Area | ft²	[1]		384,468		384,468
San Diego Properties Phase 2 [Domain]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings	[2]		6		6
Net Rentable Area | ft²	[2]		539,823		539,823
Properties Held for Sale [Member] | Von Karman, Irvine, California [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Dispositions Sales Price | $		$ 26,000
[1]	(1)The San Diego Properties - Tranche 1 include the following: 10770 Wateridge Circle, 6200 Greenwich Drive, and 6220 Greenwich Drive.
[2]	(2)The San Diego Properties - Tranche 2 include the following: 6260 Sequence Drive, 6290 Sequence, Drive, 6310 Sequence Drive, 6340 Sequence Drive, 6350 Sequence Drive, and 4921 Directors Place.

Deferred Leasing Costs and Ac48

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Details) - USD ($) $ in Thousands		Sep. 30, 2015		Dec. 31, 2014
Deferred Leasing Costs and Acquisition-related Intangible Assets, Net
Total deferred leasing costs and acquisition-related intangible assets, net		$ 173,457		$ 201,926
Acquisition-related Intangible Liabilities, Net
Total acquisitions-related intangible liabilities, net	[1]	34,425		43,427
Deferred Leasing Costs [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets, Net
Finite-lived intangible assets, gross		201,605		216,102
Finite-lived intangible assets accumulated amortization		(74,997)		(74,904)
Finite-lived intangible assets, net		126,608		141,198
Above-Market Leases [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets, Net
Finite-lived intangible assets, gross		11,026		20,734
Finite-lived intangible assets accumulated amortization		(6,380)		(13,952)
Finite-lived intangible assets, net		4,646	[2]	6,782
In-Place Leases [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets, Net
Finite-lived intangible assets, gross		74,071		97,250
Finite-lived intangible assets accumulated amortization		(32,331)		(43,773)
Finite-lived intangible assets, net		41,740		53,477
Below Market Ground Lease Obligation [Member]
Deferred Leasing Costs and Acquisition-related Intangible Assets, Net
Finite-lived intangible assets, gross		490		490
Finite-lived intangible assets accumulated amortization		(27)		(21)
Finite-lived intangible assets, net		463	[3]	469
Below Market Lease [Member]
Acquisition-related Intangible Liabilities, Net
FiniteLivedIntangibleLiabilitiesGross		55,136		68,051
Accumulated amortization		(26,632)		(30,620)
Acquisition-related Intangible Liabilities, net		28,504	[4]	37,431
Above-Market Ground Lease Obligation [Member]
Acquisition-related Intangible Liabilities, Net
FiniteLivedIntangibleLiabilitiesGross		6,320		6,320
Accumulated amortization		(399)		(324)
Acquisition-related Intangible Liabilities, net		$ 5,921	[5]	$ 5,996
[1]	Included in deferred revenue and acquisition-related intangible liabilities, net in the consolidated balance sheets.
[2]	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.
[3]	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.
[4]	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.
[5]	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.

Deferred Leasing Costs and Ac49

Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Details 1) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014	Sep. 30, 2015		Sep. 30, 2014	Dec. 31, 2014
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization Of Intangible Liabilities		$ (8,240)		$ (10,642)	$ (25,717)		$ (31,879)
Deferred Leasing Costs [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization of Intangible Assets	[1]	6,932		7,132	20,847		20,683
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014		6,740			6,740
2,015		25,662			25,662
2,016		22,661			22,661
2,017		19,023			19,023
2,018		15,150			15,150
Thereafter		37,372			37,372
Finite-lived intangible assets, net		126,608			126,608			$ 141,198
Above-Market Leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization of Intangible Assets	[2]	487		1,305	2,135		4,230
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014	[3]	399			399
2,015	[3]	1,499			1,499
2,016	[3]	1,241			1,241
2,017	[3]	831			831
2,018	[3]	643			643
Thereafter	[3]	33			33
Finite-lived intangible assets, net		4,646	[3]		4,646	[3]		6,782
In-Place Leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization of Intangible Assets	[1]	3,073		5,169	11,710		17,090
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014		2,800			2,800
2,015		10,449			10,449
2,016		9,113			9,113
2,017		6,373			6,373
2,018		4,714			4,714
Thereafter		8,291			8,291
Finite-lived intangible assets, net		41,740			41,740			53,477
Below Market Ground Lease Obligation [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization of Intangible Assets	[4]	2		2	6		6
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014	[5]	2			2
2,015	[5]	8			8
2,016	[5]	8			8
2,017	[5]	8			8
2,018	[5]	8			8
Thereafter	[5]	429			429
Finite-lived intangible assets, net		463	[5]		463	[5]		469
Below Market Leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization Of Intangible Liabilities	[6]	(2,228)		(2,940)	(8,905)		(10,054)
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014	[7]	(2,044)			(2,044)
2,015	[7]	(7,638)			(7,638)
2,016	[7]	(7,017)			(7,017)
2,017	[7]	(5,735)			(5,735)
2,018	[7]	(3,597)			(3,597)
Thereafter	[7]	(2,473)			(2,473)
Acquisition-related Intangible Liabilities, net		(28,504)	[7]		(28,504)	[7]		(37,431)
Above-Market Ground Lease Obligation [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization Of Intangible Liabilities	[8]	(26)		$ (26)	(76)		$ (76)
Estimated annual amortization related to acquisition-related intangibles
Remaining 2,014	[9]	(25)			(25)
2,015	[9]	(101)			(101)
2,016	[9]	(101)			(101)
2,017	[9]	(101)			(101)
2,018	[9]	(101)			(101)
Thereafter	[9]	(5,492)			(5,492)
Acquisition-related Intangible Liabilities, net		$ (5,921)	[9]		$ (5,921)	[9]		$ (5,996)
[1]	The amortization of deferred leasing costs related to lease incentives is recorded to rental income and other deferred leasing costs and in-place leases is recorded to depreciation and amortization expense 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]	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.
[4]	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.
[5]	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.
[6]	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.
[7]	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.
[8]	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.
[9]	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 (Details)

Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Receivables, net
Current receivables	$ 13,372	$ 9,228	[1]
Allowance for uncollectible tenant receivables	(1,839)	(1,999)	[1]
Current receivables, net	11,533	7,229	[2],[3],[4]
Deferred Rent Receivables, net
Deferred rent receivables	185,468	158,405
Allowance for deferred rent receivables	(2,116)	(1,989)
Deferred rent receivables, net	$ 183,352	$ 156,416
[1]	Excludes current receivables, net related to properties held for sale as of December 31, 2014.
[2]	All interest rates presented are fixed-rate interest rates.
[3]	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.
[4]	This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs.

Secured Debt (Details)

Secured Debt (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Secured Debt	[1]	$ 475,923	$ 546,292
Secured Debt [Member]
Debt Instrument [Line Items]
Unamortized premium		7,200	10,300
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Secured Debt		$ 475,923	546,292
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 4.27% Mortgage Payable due Feb. 01, 2018 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2]	4.27%
Effective interest rate	[2],[3]	4.27%
Maturity Date		Feb. 1, 2018
Secured Debt	[1]	$ 128,937	130,767
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 4.48% Mortgage Payable due July 1, 2027 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2],[4]	4.48%
Effective interest rate	[2],[3],[4]	4.48%
Maturity Date		Jul. 1, 2027
Secured Debt	[1],[4]	$ 96,743	97,000
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 6.05% Mortgage Payable Due June 1, 2019 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2]	6.05%
Effective interest rate	[2],[3],[4]	3.50%
Maturity Date		Jun. 1, 2019
Secured Debt	[1],[4]	$ 86,737	89,242
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 6.51% Mortgage Payable due Feb. 01, 2017 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2]	6.51%
Effective interest rate	[2],[3]	6.51%
Maturity Date		Feb. 1, 2017
Secured Debt	[1]	$ 65,841	66,647
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 5.23% Mortgage Payable due Jan. 01, 2016 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2],[4],[5]	5.23%
Effective interest rate	[2],[3],[4],[5]	3.50%
Maturity Date		Jan. 1, 2016
Secured Debt	[1],[4]	$ 51,431	52,793
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 5.57% Morgage Payable Due Feb. 11, 2016 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2],[4],[5]	5.57%
Effective interest rate	[2],[3],[4],[5]	3.25%
Maturity Date		Feb. 11, 2016
Secured Debt	[1],[4]	$ 39,188	40,258
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 5.09% Mortgage Payable due Aug. 7, 2015 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2],[6]	5.09%
Effective interest rate	[2],[3],[6]	3.50%
Maturity Date		Aug. 7, 2015
Secured Debt	[1],[5]	$ 0	34,311
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | Four Point Nine four Percent Mortgage Payable due April Fifteen Two Thousand Fifteen [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2],[6]	4.94%
Effective interest rate	[2],[3],[6]	4.00%
Maturity Date		Apr. 15, 2015
Secured Debt	[1],[5]	$ 0	26,285
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | 7.15% Mortgage Payable due May 01, 2017 [Member]
Debt Instrument [Line Items]
Annual Stated Interest Rate	[2]	7.15%
Effective interest rate	[2],[3]	7.15%
Maturity Date		May 1, 2017
Secured Debt	[1]	$ 4,649	6,568
Kilroy Realty, L.P. [Member] | Secured Debt [Member] | Municipal Bonds [Member]
Debt Instrument [Line Items]
Secured Debt	[1]	$ 2,397	$ 2,421
[1]	Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014, respectively.
[2]	All interest rates presented are fixed-rate interest rates.
[3]	This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of discounts/premiums, excluding debt issuance costs.
[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]	These mortgage notes payable were repaid in October 2015 at par.
[6]	These mortgage notes payable were repaid during the nine months ended September 30, 2015 at par.

Unsecured Senior Notes (Details

Unsecured Senior Notes (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Unsecured debt		$ 2,181,382	$ 1,783,121
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Unsecured debt		$ 2,181,382	$ 1,783,121
Kilroy Realty, L.P. [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.05%	1.25%
Debt Instrument, Contingent Additional Borrowings		$ 311,000
Kilroy Realty, L.P. [Member] | Four Point Three Seven Five Percent Unsecured Senior Notes [Member] [Domain] [Domain] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		4.375%
Effective interest rate		4.375%
Debt Instrument, Face Amount		$ 400,000	$ 0
Debt Instrument, Unamortized Discount		(2,215)	0
Unsecured debt		$ 397,785	0
Kilroy Realty, L.P. [Member] | Four Point Four Four Zero Percent Unsecured Senior Notes [Member] [Domain] [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Effective interest rate	[1],[2]	4.44%
Kilroy Realty, L.P. [Member] | Four Point Two Five Zero Percent Unsecured Senior Notes [Member] [Domain] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		4.25%
Effective interest rate	[2],[3]	4.35%
Debt Instrument, Face Amount		$ 400,000	400,000
Debt Instrument, Unamortized Discount		(4,124)	(4,348)
Unsecured debt		$ 395,876	395,652
Kilroy Realty, L.P. [Member] | 3.800% Unsecured Senior Note [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		3.80%
Effective interest rate	[2],[4]	3.804%
Debt Instrument, Face Amount		$ 300,000	300,000
Debt Instrument, Unamortized Discount		(72)	(79)
Unsecured debt		$ 299,928	299,921
Kilroy Realty, L.P. [Member] | 4.800% Unsecured Senior Notes Due July Fifteen Two Thousand Eighteen [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		4.80%
Effective interest rate	[2],[4],[5]	4.827%
Debt Instrument, Face Amount		$ 325,000	325,000
Debt Instrument, Unamortized Discount		(209)	(265)
Unsecured debt		$ 324,791	324,735
Kilroy Realty, L.P. [Member] | 6.625% Unsecured Senior Notes due June 1 2020 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		6.625%
Effective interest rate	[2],[6]	6.743%
Debt Instrument, Face Amount		$ 250,000	250,000
Debt Instrument, Unamortized Discount		(994)	(1,154)
Unsecured debt		$ 249,006	248,846
Kilroy Realty, L.P. [Member] | 5.000% Unsecured Senior Notes due Nov3 2015 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Stated coupon rate		5.00%
Effective interest rate	[2],[7]	5.014%
Debt Instrument, Face Amount		$ 325,000	325,000
Debt Instrument, Unamortized Discount		(4)	(33)
Unsecured debt		$ 324,996	324,967
Kilroy Realty, L.P. [Member] | Term Loan Facility [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maturity Date		Jul. 1, 2019
Unsecured debt		$ 150,000	$ 150,000
Debt Instrument, Basis Spread on Variable Rate	[8]	1.35%	1.56%
[1]	Interest on these notes is payable semi-annually in arrears on April 1st and October 1st of each year.
[2]	This represents the rate at which interest expense is recorded for financial reporting purposes, which reflects the amortization of initial issuance discounts, excluding debt issuance costs.
[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.
[7]	Interest on these notes is payable semi-annually in arrears on May 3rd and November 3rd of each year.
[8]	Our unsecured term loan facility interest rate was calculated based on an annual rate of LIBOR plus 1.150% and LIBOR plus 1.400% as of September 30, 2015 and December 31, 2014, respectively.

Unsecured Revolving Credit Faci

Unsecured Revolving Credit Facility (Details 3) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2015USD ($)building	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Number of Real Estate Properties | building		10
Unsecured debt		$ 2,181,382	$ 1,783,121
Terms of the Credit Facility
Unsecured line of credit		0	140,000
Kilroy Realty, L.P. [Member]
Debt Instrument [Line Items]
Unsecured debt		2,181,382	1,783,121
Terms of the Credit Facility
Unsecured line of credit		0	140,000
Kilroy Realty, L.P. [Member] | Revolving Credit Facility [Member]
Terms of the Credit Facility
Unsecured line of credit		0	140,000
Remaining borrowing capacity		600,000	460,000
Total borrowing capacity	[1]	$ 600,000	$ 600,000
Line of Credit Facility, Interest Rate at Period End	[2]	0.00%	1.41%
Line of Credit Facility, Commitment Fee Percentage	[3]	0.20%	0.25%
Line of Credit Facility, Expiration Date		Jul. 1, 2019
Debt Instrument, Contingent Additional Borrowings		$ 311,000
Debt Instrument, Basis Spread on Variable Rate		1.05%	1.25%
Debt Issuance Cost		$ 4,900
Term Loan Facility [Member] | Kilroy Realty, L.P. [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Unsecured debt		$ 150,000	$ 150,000
Terms of the Credit Facility
Debt Instrument, Basis Spread on Variable Rate	[4]	1.35%	1.56%
Maturity Date		Jul. 1, 2019
Term Loan Facility [Member] | Kilroy Realty, L.P. [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Unsecured debt		$ 39,000
London Interbank Offered Rate (LIBOR) [Member] | Term Loan Facility [Member] | Kilroy Realty, L.P. [Member] | Line of Credit [Member]
Terms of the Credit Facility
Debt Instrument, Basis Spread on Variable Rate		1.15%	1.40%
[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 term loan facility.
[2]	Our unsecured revolving credit facility interest rate was calculated based on an annual rate of LIBOR plus 1.050% and LIBOR plus 1.250% as of September 30, 2015 and December 31, 2014, respectively.
[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 September 30, 2015, $4.9 million of deferred financing costs remains to be amortized through the maturity date of our unsecured revolving credit facility.
[4]	Our unsecured term loan facility interest rate was calculated based on an annual rate of LIBOR plus 1.150% and LIBOR plus 1.400% as of September 30, 2015 and December 31, 2014, respectively.

Debt Maturities (Details)

Debt Maturities (Details) - Debt [Member] - Kilroy Realty, L.P. [Member] $ in Thousands	Sep. 30, 2015USD ($)
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Remaining 2,015	$ 327,768
2,016	99,431
2,017	71,748
2,018	451,728
2,019	265,370
Thereafter	1,441,643
Total	2,657,688	[1]
Unamortized premium	$ (400)
[1]	Includes gross principal balance of outstanding debt before impact of net unamortized discounts totaling approximately $0.4 million

Secured and Unsecured Debt of55

Secured and Unsecured Debt of the Operating Partnership Capitalized Interest and Loan Fees (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Capitalized Interest and Loan Fees [Line Items]
Interest Expense	$ 12,819	$ 16,608	$ 44,561	$ 49,880
Kilroy Realty, L.P. [Member]
Capitalized Interest and Loan Fees [Line Items]
Gross interest expense	27,386	29,936	82,322	85,740
Capitalized interest	(14,567)	(13,328)	(37,761)	(35,860)
Interest Expense	$ 12,819	$ 16,608	$ 44,561	$ 49,880

Noncontrolling Interests on t56

Noncontrolling Interests on the Company's Consolidated Financial Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Noncontrolling Interest [Abstract]
Percentage of general partnership interest owned by the company in the Operating Partnership	98.10%	98.00%	97.90%
Percentage of Common limited partnership interest owned by certain non-affiliated investors and certain directors and officers of the Company in the Operating Partnership	1.90%	2.00%	2.10%
Common units outstanding held by common limited partners	1,788,170	1,804,200	1,804,200
Common stock, par value	$ 0.01
Aggregate value upon redemption of outstanding noncontrolling common units	$ 118,000	$ 126,800
Noncontrolling Interest in Variable Interest Entity	$ 6,336	$ 5,862

Stockholders' Equity of the C57

Stockholders' Equity of the Company (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Jul. 01, 2015	Dec. 31, 2014
Common Stock of the Company [Abstract]
Net proceeds from issuance of common stock (Note 8)		$ 387,509	$ 22,136
Common stock, shares issued				3,773,766
Shares Issued, Price Per Share				$ 66.19
At Market Stock Aggregate Gross Sales Price of Common Stock				$ 249,800
Proceeds from Issuance of Common stock, net	$ 249,600
Common Stock [Member]
Common Stock of the Company [Abstract]
Common stock, shares issued	88,405,632	88,405,632			86,259,684
Issuance of Equity - at the market offering [Member] | Common Stock [Member]
Common Stock of the Company [Abstract]
At Market Stock Aggregate Gross Sales Price of Common Stock	$ 150,100	$ 150,100
December 2014 At-The-Market Program [Member] | Common Stock [Member]
Common Stock of the Company [Abstract]
Common stock, shares issued	2,007,767	2,007,767
Issuance of Equity - at the market offering [Member] | Common Stock [Member]
Class of Stock [Line Items]
At Market Stock Offering Program Aggregate Value Of Common Stock		$ 300,000
Common Stock of the Company [Abstract]
Issuance of common stock, shares (Note 8)		1,866,267
Average price per common shares sold		$ 75.06
Net proceeds from issuance of common stock (Note 8)		$ 140,100
At the Market Stock Offering Program Remained Available For Issuance		149,900
Proceeds from Issuance of Common stock, net		$ 138,200

Partners' Capital of the Oper58

Partners' Capital of the Operating Partnership (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
General Partners' Capital Account [Abstract]
Net proceeds from issuance of common stock	$ 387,509	$ 22,136
Noncontrolling Interest, Ownership Percentage by Parent	98.10%	97.90%	98.00%
Common units held by limited partners	1,788,170	1,804,200	1,804,200
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	1.90%	2.10%	2.00%
Kilroy Realty, L.P. [Member] | Capital Units [Member]
General Partners' Capital Account [Abstract]
General Partners' Capital Account, Units Outstanding	92,220,367	83,388,220	86,259,684

Share-Based Compensation (Detai

Share-Based Compensation (Details Textuals) - USD ($) $ / shares in Units, $ in Millions	Jan. 27, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
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
Share Price	$ 75.34
Share-based Compensation Capitalized		$ 0.7	$ 0.6	$ 2.3	$ 1.5
Share-based Compensation, Unrecognized costs		35.2		$ 35.2
Share-based Compensation, Unrecognized costs, weighted-average vesting period				2 years 1 month
Allocated Share-based Compensation Expense		$ 4.3	$ 4	$ 13.6	$ 10.3
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, Weighted Average Grant Date Fair Value	$ 78.55
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate				20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate				0.92%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				127,657
Share-based Compensation Arrangement by Share-based Payment Award, Options, Other Increases (Decreases) in Period		168,788		168,788
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	2 years 11 months
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Grants In Period, Grant Date Fair Value				$ 10.1
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				84,811
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Grants In Period, Grant Date Fair Value				$ 6.4
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price				$ 42.61
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term		687,000		687,000
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		1,724,324		1,724,324
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Paid for Tax Withholding for Share Based Compensation				39,317	48,017
Exercise of stock options				(265,000)	(482,000)
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		8,320,000

Commitments and Contingencies (

Commitments and Contingencies (Details 1) $ in Millions	Sep. 30, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
Other Commitment	$ 481.2
Accrued Environmental Loss Contingencies, Noncurrent	$ 19.4

Fair Value Measurements and D61

Fair Value Measurements and Disclosures (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Fair value adjustment of marketable securities and deferred compensation plan liability
Net gain on marketable securities		$ (681)	$ (39)	$ (171)	$ 507
Trading Securities		12,638		12,638		$ 11,971
Fair Value (Level 1) [Member]
Assets and Liabilities Reported at Fair Value
Marketable securities	[1],[2]	$ 12,638		$ 12,638		$ 11,971
[1]	Based on quoted prices in active markets for identical securities.
[2]	The marketable securities are held in a limited rabbi trust.

Fair Value Measurements and D62

Fair Value Measurements and Disclosures (Details 1) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Liabilities
Secured Debt	[1]	$ 475,923	$ 546,292
Unsecured debt		2,181,382	1,783,121
Unsecured line of credit		0	140,000
Carrying Value
Liabilities
Secured Debt	[2]	475,923	546,292
Unsecured debt	[3]	2,181,382	1,783,121
Unsecured line of credit	[2],[4]	0	140,000
Carrying Value | Fair Value (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure		189,000	513,700
Carrying Value | Unsecured Debt [Member] | Fair Value (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure		1,992,300	1,269,400
Fair Value
Liabilities
Secured Debt	[2]	487,563	559,483
Unsecured debt	[3]	2,228,225	1,858,492
Unsecured line of credit	[2],[4]	0	145,051
Fair Value | Fair Value (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure		189,000	536,300
Fair Value | Unsecured Debt [Member] | Fair Value (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure		$ 2,039,200	$ 1,322,200
[1]	Amounts reported include the amounts of unamortized debt premiums of $7.2 million and $10.3 million as of September 30, 2015 and December 31, 2014, respectively.
[2]	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.
[3]	Fair value calculated using Level I and Level II inputs. Level I inputs are based on quoted prices for identical instruments in active markets. The carrying value and fair value of the Level I instruments was $2.0 billion and $2.0 billion, respectively, as of September 30, 2015. The carrying value and fair value of the Level I instruments as of December 31, 2014, was $1.3 billion and $1.3 billion, respectively. The carrying value and fair value of the Level II instruments was $189.0 million and $189.0 million, respectively, as of September 30, 2015. The carrying value and fair value of the Level II instruments as of December 31, 2014, was $513.7 million and $536.3 million, respectively.
[4]	There was no outstanding balance on the unsecured line of credit as of September 30, 2015.

Net Income Available to Commo63

Net Income Available to Common Stockholders Per Share of the Company (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014
Numerator:
Income from continuing operations		$ 106,704		$ 13,168		$ 209,296	$ 39,896
(Income) Loss from continuing operations attributable to noncontrolling common units of the Operating Partnership		(1,945)		(193)		(3,850)	(635)
Preferred dividends		(3,313)		(3,313)		(9,938)	(9,938)
Allocation to participating securities	[1]	(367)		(432)		(1,200)	(1,285)
Numerator for basic and diluted income from continuing operations available to common stockholders		101,079		9,230		194,308	28,038
Income from discontinued operations	[2]	0		6,135		0	112,482
Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership	[2]	0		(128)		0	(2,376)
Numerator for basic and diluted net income available to common stockholders		$ 101,079		$ 15,237		$ 194,308	$ 138,144
Denominator:
Weighted average common shares outstanding – basic (Note 13)		92,150,341		83,161,323		89,077,012	82,525,033
Effect of dilutive securities		488,724		1,949,133		516,249	2,097,589
Weighted average common shares outstanding-diluted		92,639,065		85,110,456		89,593,261	84,622,622
Basic earnings per share:
Income (loss) from continuing operations available to common stockholders per common share – basic (Note 13)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income from discontinued operations per common share	[2]	0		0.07		0	1.33
Net income available to common stockholders per share-basic		1.10		0.18		2.18	1.67
Diluted earnings per share:
Income from continuing operations available to common stockholders per common share – diluted (Note 13)		1.09		0.11		2.17	0.33
Income from discontinued operations per common share	[2]	0		0.07		0	1.30
Net income available to common stockholders per share-diluted		$ 1.09		$ 0.18		$ 2.17	$ 1.63
Kilroy Realty, L.P. [Member]
Numerator:
Income from continuing operations		$ 106,704		$ 13,168		$ 209,296	$ 39,896
(Income) Loss from continuing operations attributable to noncontrolling common units of the Operating Partnership		(64)		(59)		(211)	(188)
Preferred dividends		(3,313)		(3,313)		(9,938)	(9,938)
Allocation to participating securities	[3]	(367)		(432)		(1,200)	(1,285)
Numerator for basic and diluted income from continuing operations available to common stockholders		102,960		9,364		197,947	28,485
Income from discontinued operations		0	[4]	6,135	[4]	0	112,482	[4]
Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership	[4]	0		0		0	(13)
Numerator for basic and diluted net income available to common stockholders		$ 102,960		$ 15,499		$ 197,947	$ 140,954
Denominator:
Weighted average common shares outstanding – basic (Note 13)		93,938,783		84,965,523		90,869,696	84,329,317
Effect of dilutive securities		488,724		1,949,133		516,249	2,097,589
Weighted average common shares outstanding-diluted		94,427,507		86,914,656		91,385,945	86,426,906
Basic earnings per share:
Income (loss) from continuing operations available to common stockholders per common share – basic (Note 13)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income from discontinued operations per common share	[4]	0		0.07		0	1.33
Net income available to common stockholders per share-basic		1.10		0.18		2.18	1.67
Diluted earnings per share:
Income from continuing operations available to common stockholders per common share – diluted (Note 13)		1.09		0.11		2.17	0.33
Income from discontinued operations per common share	[4]	0		0.07		0	1.30
Net income available to common stockholders per share-diluted		$ 1.09		$ 0.18		$ 2.17	$ 1.63
[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 1). 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.
[3]	Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs.
[4]	The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 1). 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 Commo64

Net Income Available to Common Unitholders Per Unit of the Operating Partnership (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014
Numerator:
Income from continuing operations		$ 106,704		$ 13,168		$ 209,296	$ 39,896
(Income) Loss from continuing operations attributable to noncontrolling common units of the Operating Partnership		(1,945)		(193)		(3,850)	(635)
Preferred distributions		(3,313)		(3,313)		(9,938)	(9,938)
Allocation to participating securities	[1]	(367)		(432)		(1,200)	(1,285)
Numerator for basic and diluted income from continuing operations available to common unitholders		101,079		9,230		194,308	28,038
Income from discontinued operations	[2]	0		6,135		0	112,482
Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership	[2]	0		(128)		0	(2,376)
Numerator for basic and diluted net income available to common unitholders		$ 101,079		$ 15,237		$ 194,308	$ 138,144
Denominator:
Weighted average common units outstanding - basic (Note 14)		92,150,341		83,161,323		89,077,012	82,525,033
Effect of dilutive securities		488,724		1,949,133		516,249	2,097,589
Weighted average common units outstanding - diluted (Note 14)		92,639,065		85,110,456		89,593,261	84,622,622
Basic earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit - basic (Note 14)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income from discontinued operations per common unit	[2]	0		0.07		0	1.33
Net income available to common unitholders per unit-basic (Note 14)		1.10		0.18		2.18	1.67
Diluted earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit - diluted (Note 15)		1.09		0.11		2.17	0.33
Income from discontinued operations per common unit	[2]	0		0.07		0	1.30
Net income available to common unitholders per unit-diluted (Note 14)		$ 1.09		$ 0.18		$ 2.17	$ 1.63
Kilroy Realty, L.P. [Member]
Numerator:
Income from continuing operations		$ 106,704		$ 13,168		$ 209,296	$ 39,896
(Income) Loss from continuing operations attributable to noncontrolling common units of the Operating Partnership		(64)		(59)		(211)	(188)
Preferred distributions		(3,313)		(3,313)		(9,938)	(9,938)
Allocation to participating securities	[3]	(367)		(432)		(1,200)	(1,285)
Numerator for basic and diluted income from continuing operations available to common unitholders		102,960		9,364		197,947	28,485
Income from discontinued operations		0	[4]	6,135	[4]	0	112,482	[4]
Income from discontinued operations attributable to noncontrolling common units of the Operating Partnership	[4]	0		0		0	(13)
Numerator for basic and diluted net income available to common unitholders		$ 102,960		$ 15,499		$ 197,947	$ 140,954
Denominator:
Weighted average common units outstanding - basic (Note 14)		93,938,783		84,965,523		90,869,696	84,329,317
Effect of dilutive securities		488,724		1,949,133		516,249	2,097,589
Weighted average common units outstanding - diluted (Note 14)		94,427,507		86,914,656		91,385,945	86,426,906
Basic earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit - basic (Note 14)		$ 1.10		$ 0.11		$ 2.18	$ 0.34
Income from discontinued operations per common unit	[4]	0		0.07		0	1.33
Net income available to common unitholders per unit-basic (Note 14)		1.10		0.18		2.18	1.67
Diluted earnings per unit:
Income (loss) from continuing operations available to common unitholders per unit - diluted (Note 15)		1.09		0.11		2.17	0.33
Income from discontinued operations per common unit	[4]	0		0.07		0	1.30
Net income available to common unitholders per unit-diluted (Note 14)		$ 1.09		$ 0.18		$ 2.17	$ 1.63
[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 1). 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.
[3]	Participating securities include nonvested shares, certain time-based RSUs and vested market measure-based RSUs.
[4]	The Company adopted ASU 2014-08 effective January 1, 2015 (see Note 1). 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.

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands	Oct. 22, 2015	Oct. 14, 2015	Sep. 30, 2015	Sep. 30, 2014
Subsequent Event [Line Items]
Aggregate dividends, distributions, and dividend equivalents paid to common stockholders and common unitholders			$ 93,910	$ 88,540
Repayments of Secured Debt			$ 67,335	$ 7,315
Subsequent Event [Member]
Subsequent Event [Line Items]
Aggregate dividends, distributions, and dividend equivalents paid to common stockholders and common unitholders		$ 33,300
Repayments of Secured Debt	$ 90,100