Supplemental Cash Flow Information of the Operating Partnership - Supplemental Cash Flow (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
SUPPLEMENTAL CASH FLOWS INFORMATION:
Capitalized interest	$ 18,029	$ 16,131
Cash paid for interest, net of capitalized interest of $18,029 and $16,131 as of March 31, 2022 and 2021, respectively	4,736	12,387
Cash paid for amounts included in the measurement of ground lease liabilities	1,532	1,455
NON-CASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	47,101	57,675
Tenant improvements funded directly by tenants	1,908	2,570
NON-CASH FINANCING TRANSACTIONS:
Accrual of distributions payable to common unitholders (Note 15)	61,951	59,472
Kilroy Realty L.P.
SUPPLEMENTAL CASH FLOWS INFORMATION:
Capitalized interest	18,029	16,131
Cash paid for interest, net of capitalized interest of $18,029 and $16,131 as of March 31, 2022 and 2021, respectively	4,736	12,387
Cash paid for amounts included in the measurement of ground lease liabilities	1,532	1,455
NON-CASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	47,101	57,675
Tenant improvements funded directly by tenants	1,908	2,570
NON-CASH FINANCING TRANSACTIONS:
Accrual of distributions payable to common unitholders (Note 15)	$ 61,951	$ 59,472