Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - Kilroy Realty L.P. $ in Thousands	9 Months Ended
Sep. 30, 2024 USD ($) extension_option
Stated debt maturities and scheduled amortization payments
Remaining 2024	$ 405,235
2025	606,246
2026	401,317
2027	249,125
2028	400,000
2029	475,000
Thereafter	2,500,000
Total aggregate principal value	5,036,923
Less: unamortized net discounts and deferred financing costs	(35,767)
Total debt, net	5,001,156
Unsecured Debt \| 2024 Term Loan Facility
Stated debt maturities and scheduled amortization payments
Total debt, net	$ 200,000
Number of extension options \| extension_option	2
Extension period (in months)	12 months
Unsecured Senior Notes
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	$ 27,000
Senior Notes
Stated debt maturities and scheduled amortization payments
Debt issuance discount	$ 8,800

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