Consolidated Statements of Capital (KILROY REALTY, L.P.) - Parenthetical - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Kilroy Realty L.P. [Member]
Distributions declared per common unit (in dollars per units)	$ 1.79000	$ 1.65000	$ 3.375

Cash dividends declared or paid to each outstanding limited partnership and general partnership unit during the reporting period.

No definition available.

Name:	us-gaap_DistributionsPerLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasic
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration