Number of Noncompliant Debt Covenants that Could Require Immediate Repayment of Full Principal Balance

No definition available.

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- Definition

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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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Gross amount of debt extinguished.

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No definition available.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Secured and Unsecured Debt of the Operating Partnership - Additional Information (Details) $ in Thousands	1 Months Ended	9 Months Ended
	Sep. 30, 2025 USD ($) debt_covenant	Sep. 30, 2025 USD ($) debt_covenant	Sep. 30, 2024 USD ($)	Aug. 31, 2025 USD ($)
Debt Instrument [Line Items]
Proceeds from the issuance of unsecured debt (Note 5)		$ 395,964	$ 395,516
Kilroy Realty L.P.
Debt Instrument [Line Items]
Total aggregate principal value	$ 4,627,026	4,627,026
Proceeds from the issuance of unsecured debt (Note 5)		$ 395,964	$ 395,516
Number of noncompliant debt covenants that could require immediate repayment of full principal balance of associated debt \| debt_covenant	1	1
5.875% Unsecured Senior Notes Due 2036 \| Unsecured debt, net \| Kilroy Realty L.P.
Debt Instrument [Line Items]
Total aggregate principal value				$ 400,000
Debt Instrument, Unamortized Discount (Premium), Net				$ (4,000)
Stated interest rate on debt (percent)	5.875%	5.875%		5.875%
Proceeds from the issuance of unsecured debt (Note 5)	$ 400,000
Repayment of debt	$ 400,000
4.375% Unsecured Senior Notes Due 2036 \| Unsecured debt, net \| Kilroy Realty L.P.
Debt Instrument [Line Items]
Stated interest rate on debt (percent)	4.375%	4.375%