Supplemental Cash Flow Information of the Operating Partnership - Reconciliation of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents	$ 625,395	$ 510,163	$ 618,794	$ 347,379
Restricted cash	0	0	0	0
Cash and cash equivalents and restricted cash	625,395	510,163	618,794	347,379
Kilroy Realty L.P.
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents	625,395	510,163	618,794	347,379
Restricted cash	0	0	0	0
Cash and cash equivalents and restricted cash	$ 625,395	$ 510,163	$ 618,794	$ 347,379