Secured and Unsecured Debt of the Operating Partnership - Additional Information (Details) - USD ($)	Jun. 30, 2023	Mar. 31, 2023	Jan. 31, 2023	Dec. 31, 2022
Term Loan
Debt Instrument [Line Items]
Term loan facility, additional borrowing capacity			$ 100,000,000
Term loan facility, maximum borrowing capacity			$ 650,000,000
Term loan facility, accordion feature for additional term loan commitments		$ 20,000,000
Kilroy Realty L.P. | Revolving credit facility
Debt Instrument [Line Items]
Term loan facility, maximum borrowing capacity	$ 1,100,000,000			$ 1,100,000,000
Kilroy Realty L.P. | Term Loan Facility | Unsecured Term Loan Facility
Debt Instrument [Line Items]
Term loan facility, maximum borrowing capacity	$ 520,000,000			$ 400,000,000