Consolidated Statements of Capital (KILROY REALTY, L.P.) (Kilroy Realty, L.P. [Member], USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Total Partners Capital [Member]	Mar. 31, 2013 Total Partners Capital [Member]	Mar. 31, 2014 Partners Capital Preferred Units [Member]	Dec. 31, 2013 Partners Capital Preferred Units [Member]	Mar. 31, 2013 Partners Capital Preferred Units [Member]	Dec. 31, 2012 Partners Capital Preferred Units [Member]	Mar. 31, 2014 Partners Capital Common Unit [Member]	Mar. 31, 2013 Partners Capital Common Unit [Member]	Mar. 31, 2014 Noncontrolling Interest In Consolidated Subsidiaries [Member]	Mar. 31, 2013 Noncontrolling Interest In Consolidated Subsidiaries [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 2,516,160	$ 2,235,933	$ 2,507,772	$ 2,232,654	$ 192,411	$ 192,411	$ 192,411	$ 192,411	$ 2,315,361	$ 2,040,243	$ 8,388	$ 3,279
Beginning Balance units									83,959,144	76,753,484
Net income	101,932	2,388	101,867	2,319					101,867	2,319	65	69
Issuance of common units										453,679
Issuance of common units		23,395		23,395						23,395
Issuance of share-based compensation awards, units										0
Partners' Capital Account, Unit-based Compensation										336
Issuance of share-based compensation awards		336		336
Noncash amortization of share-based compensation	2,233	2,422	2,233	2,422					2,233	2,422
Repurchase of common units and restricted stock units, shares									(26,074)	(33,534)
Repurchase of common units and restricted stock units	(1,517)	1,199	(1,517)	(1,199)					(1,517)	(1,199)
Settlement of restricted stock units, shares									88,962	2,579
Settlement of restricted stock units									0	(10)
Settlement of restricted stock units	0	(10)	0	(10)
Exercise of stock options, net, units									500
Exercise of stock options, net	21		21						21
Dividends, Preferred Stock	(3,313)	(3,313)	(3,313)	(3,313)					(3,313)	(3,313)
Partners' Capital Account, Distributions									(29,906)	(27,412)
Distributions declared per common unit ($1.05 per unit)	(29,906)	(27,412)	(29,906)	(27,412)
Ending Balance	$ 2,585,610	$ 2,232,540	$ 2,577,157	$ 2,229,192	$ 192,411	$ 192,411	$ 192,411	$ 192,411	$ 2,384,746	$ 2,036,781	$ 8,453	$ 3,348
Ending Balance units									84,022,532	77,176,208