Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - Kilroy Realty L.P. - USD ($) $ in Thousands	1 Months Ended
Aug. 31, 2020	Dec. 31, 2021
Stated debt maturities and scheduled amortization payments, excluding debt discounts
2022		$ 5,554
2023		5,775
2024		431,006
2025		406,246
2026		401,317
Thereafter		2,849,125
Total aggregate principal value		4,099,023
Line of credit \| $150.0 million term loan facility
Debt Disclosure [Abstract]
Extinguishment of debt	$ 150,000
Unsecured Term Loan Facility, Unsecured Senior Notes and Secured Debt
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Unamortized debt issuance expense		(22,900)
Unsecured senior notes
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Debt issuance discount		$ (7,400)

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Gross amount of debt extinguished.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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