Consolidated Statements of Operations (KILROY REALTY, L.P.) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
REVENUES:
Rental income	$ 107,380	$ 84,349
Tenant reimbursements	9,887	7,180
Other property income	230	868
Total revenues	117,497	92,397
EXPENSES:
Property expenses	23,773	16,132
Real estate taxes	10,337	7,665
Provision for bad debts	95	2
Ground leases (Note 3)	847	807
General and administrative expenses	9,669	8,767
Acquisition-related expenses	655	1,528
Depreciation and amortization	50,391	34,652
Total expenses	95,767	69,553
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (Note 11)	392	484
Interest expense (Note 5)	(19,734)	(21,163)
Total other (expenses) income	(19,342)	(20,679)
INCOME FROM CONTINUING OPERATIONS	2,388	2,165
DISCONTINUED OPERATIONS
Income from discontinued operations	0	3,697
Net gain on dispositions of discontinued operations	0	72,809
Total income from discontinued operations	0	76,506
NET INCOME	2,388	78,671
NET INCOME ATTRIBUTABLE TO KILROY REALTY, L.P.	2,410	76,876
Preferred distributions	(3,313)	(4,418)
Original issuance costs of redeemed preferred units	0	(4,918)
Total preferred distributions	(3,313)	(9,336)
NET (LOSS) INCOME AVAILABLE TO COMMON UNITHOLDERS	(903)	67,540
Loss from continuing operations available to common unitholders per common unit-basic (Note 13)	$ (0.02)	$ (0.12)
Loss from continuing operations available to common unitholders per common unit-diluted (Note 13)	$ (0.02)	$ (0.12)
Net (loss) income available to common unitholders per unit-basic (Note 13)	$ (0.02)	$ 1.06
Net (loss) income available to common unitholders per unit-diluted (Note 13)	$ (0.02)	$ 1.06
Weighted average common units outstanding - basic (Note 13)	74,977,240	63,648,704
Weighted average common units outstanding - diluted (Note 13)	74,977,240	63,648,704
Kilroy Realty, L.P. [Member]
REVENUES:
Rental income	107,380	84,349
Tenant reimbursements	9,887	7,180
Other property income	230	868
Total revenues	117,497	92,397
EXPENSES:
Property expenses	23,773	16,132
Real estate taxes	10,337	7,665
Provision for bad debts	95	2
Ground leases (Note 3)	847	807
General and administrative expenses	9,669	8,767
Acquisition-related expenses	655	1,528
Depreciation and amortization	50,391	34,652
Total expenses	95,767	69,553
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (Note 11)	392	484
Interest expense (Note 5)	(19,734)	(21,163)
Total other (expenses) income	(19,342)	(20,679)
INCOME FROM CONTINUING OPERATIONS	2,388	2,165
DISCONTINUED OPERATIONS
Income from discontinued operations	0	3,697
Net gain on dispositions of discontinued operations	0	72,809
Total income from discontinued operations	0	76,506
NET INCOME	2,388	78,671
Net income attributable to noncontrolling interests in consolidated subsidiaries	(69)	(53)
NET INCOME ATTRIBUTABLE TO KILROY REALTY, L.P.	2,319	78,618
Preferred distributions	(3,313)	(4,418)
Original issuance costs of redeemed preferred units	0	(4,918)
Total preferred distributions	(3,313)	(9,336)
NET (LOSS) INCOME AVAILABLE TO COMMON UNITHOLDERS	$ (994)	$ 69,282
Loss from continuing operations available to common unitholders per common unit-basic (Note 13)	$ (0.02)	$ (0.12)
Loss from continuing operations available to common unitholders per common unit-diluted (Note 13)	$ (0.02)	$ (0.12)
Net (loss) income available to common unitholders per unit-basic (Note 13)	$ (0.02)	$ 1.05
Net (loss) income available to common unitholders per unit-diluted (Note 13)	$ (0.02)	$ 1.05
Weighted average common units outstanding - basic (Note 13)	76,803,743	65,366,835
Weighted average common units outstanding - diluted (Note 13)	76,803,743	65,366,835
Distributions declared per common unit	$ 0.35	$ 0.35