Consolidated Statements of Capital (KILROY REALTY, L.P.) (Parenthetical) - $ / shares	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Kilroy Realty L.P. [Member]
Dividends declared per common unit (in dollars per unit)	$ 0.455000	$ 0.425000	$ 1.335000	$ 1.225000

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