Consolidated Statements of Operations (KILROY REALTY, L.P.) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
REVENUES
Rental income	$ 158,925	$ 143,653	$ 315,573	$ 277,408
Tenant reimbursements	19,267	16,138	38,563	27,542
Other property income	2,406	342	5,770	629
Total revenues	180,598	160,133	359,906	305,579
EXPENSES
Property expenses	33,304	29,221	64,545	55,186
Real estate taxes	16,543	13,845	34,507	24,877
Provision for bad debts	409	0	1,707	0
Ground leases	1,547	768	3,189	1,597
General and administrative expenses	14,303	13,979	29,236	27,416
Acquisition-related expenses (Note 1)	0	714	0	776
Depreciation and amortization	62,251	53,346	123,170	103,786
Total expenses	128,357	111,873	256,354	213,638
OTHER (EXPENSES) INCOME
Interest income and other net investment gains (Note 11)	1,038	311	2,103	582
Interest expense (Note 5)	(17,973)	(14,384)	(35,325)	(26,213)
Total other (expenses) income	(16,935)	(14,073)	(33,222)	(25,631)
Net loss on sale of land	0	(295)	0	(295)
Gains on sales of depreciable operating properties (Note 2)	0	0	2,257	145,990
NET INCOME	35,306	33,892	72,587	212,005
Net income attributable to noncontrolling interests in consolidated property partnerships and subsidiaries	(3,858)	(1,045)	(7,614)	(4,850)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION (KILROY REALTY, L.P.)	31,448	32,847	64,973	207,155
Original issuance costs of redeemed preferred stock (preferred units)	0	0	(3,845)	0
Total preferred dividends	(1,615)	(3,312)	(8,811)	(6,625)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS (UNITHOLDERS)	$ 29,833	$ 29,535	$ 56,162	$ 200,530
Net income available to common unitholders per unit-basic (in dollars per unit) (Note 13)	$ 0.30	$ 0.32	$ 0.56	$ 2.17
Net income available to common unitholders per unit-diluted (in dollars per unit) (Note 13)	$ 0.30	$ 0.31	$ 0.56	$ 2.15
Weighted average common units outstanding - basic (in units)	98,275,471	92,209,955	97,834,255	92,217,238
Weighted average common units outstanding - diluted (in units)	98,827,378	92,824,786	98,427,345	92,784,065
Kilroy Realty, L.P. [Member]
REVENUES
Rental income	$ 158,925	$ 143,653	$ 315,573	$ 277,408
Tenant reimbursements	19,267	16,138	38,563	27,542
Other property income	2,406	342	5,770	629
Total revenues	180,598	160,133	359,906	305,579
EXPENSES
Property expenses	33,304	29,221	64,545	55,186
Real estate taxes	16,543	13,845	34,507	24,877
Provision for bad debts	409	0	1,707	0
Ground leases	1,547	768	3,189	1,597
General and administrative expenses	14,303	13,979	29,236	27,416
Acquisition-related expenses (Note 1)	0	714	0	776
Depreciation and amortization	62,251	53,346	123,170	103,786
Total expenses	128,357	111,873	256,354	213,638
OTHER (EXPENSES) INCOME
Interest income and other net investment gains (Note 11)	1,038	311	2,103	582
Interest expense (Note 5)	(17,973)	(14,384)	(35,325)	(26,213)
Total other (expenses) income	(16,935)	(14,073)	(33,222)	(25,631)
INCOME FROM OPERATIONS BEFORE GAINS (LOSS) ON SALES OF REAL ESTATE	35,306	34,187	70,330	66,310
Net loss on sale of land	0	(295)	0	(295)
Gains on sales of depreciable operating properties (Note 2)	0	0	2,257	145,990
NET INCOME	35,306	33,892	72,587	212,005
Net income attributable to noncontrolling interests in consolidated property partnerships and subsidiaries	(3,335)	(302)	(6,562)	(582)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION (KILROY REALTY, L.P.)	31,971	33,590	66,025	211,423
Preferred distributions	(1,615)	(3,312)	(4,966)	(6,625)
Original issuance costs of redeemed preferred stock (preferred units)	0	0	(3,845)	0
Total preferred dividends	(1,615)	(3,312)	(8,811)	(6,625)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS (UNITHOLDERS)	$ 30,356	$ 30,278	$ 57,214	$ 204,798
Net income available to common unitholders per unit-basic (in dollars per unit) (Note 13)	$ 0.30	$ 0.31	$ 0.56	$ 2.16
Net income available to common unitholders per unit-diluted (in dollars per unit) (Note 13)	$ 0.30	$ 0.31	$ 0.56	$ 2.15
Weighted average common units outstanding - basic (in units)	100,352,664	94,841,231	100,024,000	94,514,876
Weighted average common units outstanding - diluted (in units)	100,904,571	95,456,062	100,617,090	95,081,703
Dividends declared per common unit (in dollars per unit)	$ 0.425	$ 0.375	$ 0.8	$ 0.725000