Supplemental Cash Flow Information of the Operating Partnership - Reconciliation of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents	$ 331,685	$ 414,077	$ 657,819	$ 731,991
Restricted cash	13,007	13,006	1,028,759	91,139
Cash and cash equivalents and restricted cash	344,692	427,083	1,686,578	823,130
Kilroy Realty L.P.
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents	331,685	414,077	657,819	731,991
Restricted cash	13,007	13,006	1,028,759	91,139
Cash and cash equivalents and restricted cash	$ 344,692	$ 427,083	$ 1,686,578	$ 823,130