Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - Kilroy Realty L.P. $ in Thousands	3 Months Ended
Mar. 31, 2023 USD ($) extension_option
Stated debt maturities and scheduled amortization payments
Remaining 2023	$ 4,352
2024	781,006
2025	406,246
2026	401,317
2027	249,125
2028	400,000
Thereafter	2,200,000
Total aggregate principal value	$ 4,442,046
Unsecured Debt \| Unsecured Term Loan Facility
Stated debt maturities and scheduled amortization payments
Number of extension options \| extension_option	2
Extension period (in months)	12 months
Unsecured Term Loan Facility, Unsecured Senior Notes and Secured Debt
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	$ 23,400
Senior Notes
Stated debt maturities and scheduled amortization payments
Debt issuance discount	$ 6,100

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