Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	$ 10,921	$ 12,692
Kilroy Realty L.P.
Stated debt maturities and scheduled amortization payments
Remaining 2025	603,153
2026	401,317
2027	249,125
2028	400,000
2029	475,000
2030	500,000
Thereafter	2,000,000
Total aggregate principal value	4,628,595
Less: unamortized net discounts and deferred financing costs	(30,876)
Total debt, net	4,597,719
Kilroy Realty L.P. \| Unsecured Senior Notes
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	23,100
Kilroy Realty L.P. \| Senior Notes
Stated debt maturities and scheduled amortization payments
Debt issuance discount	$ 7,700

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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