Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025 USD ($) extension_option	Dec. 31, 2024 USD ($)
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	$ 11,806	$ 12,692
Kilroy Realty L.P.
Stated debt maturities and scheduled amortization payments
Remaining 2025	604,707
2026	401,317
2027	249,125
2028	400,000
2029	475,000
2030	500,000
Thereafter	2,000,000
Total aggregate principal value	4,630,149
Less: unamortized net discounts and deferred financing costs	(32,307)
Total debt, net	4,597,842
Kilroy Realty L.P. \| 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	12 months
Kilroy Realty L.P. \| Unsecured Senior Notes
Stated debt maturities and scheduled amortization payments
Unamortized debt issuance expense	$ 24,200
Kilroy Realty L.P. \| Senior Notes
Stated debt maturities and scheduled amortization payments
Debt issuance discount	$ 8,100

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