Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - Kilroy Realty L.P. $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024 USD ($) extension_option	Dec. 31, 2023 USD ($)
Stated debt maturities and scheduled amortization payments
Remaining 2024	$ 528,238
2025	606,246
2026	401,317
2027	249,125
2028	400,000
2029	475,000
Thereafter	2,500,000
Total aggregate principal value	5,159,926
Unsecured Debt \| 2022 Term Loan Facility
Stated debt maturities and scheduled amortization payments
Long-term debt	$ 120,000
Number of extension options \| extension_option	2
Extension period (in months)	12 months
Unsecured Debt \| 2024 Term Loan Facility
Stated debt maturities and scheduled amortization payments
Long-term debt	$ 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	$ 30,200
Senior Notes
Stated debt maturities and scheduled amortization payments
Debt issuance discount	$ 9,500
Term Loan Facility \| 2022 Term Loan Facility
Stated debt maturities and scheduled amortization payments
Extension period (in months)	12 months	12 months
Unamortized debt issuance expense		$ 2,300

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