Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

No definition available.

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- Definition

Line of Credit Facility, Additional Maximum Borrowing Capacity

+ References

No definition available.

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- Definition

Number of Apartment Units

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Number of Office Buildings

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- Definition

Payments for Repurchase of Unsecured Debt

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- Definition

Area of a real estate property.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Secured and Unsecured Debt of the Operating Partnership - Additional Information (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jul. 31, 2023 USD ($) ft² office_building apartment_unit	Mar. 31, 2023 USD ($)	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Repurchases of unsecured debt		$ 14,290,000	$ 0
Remaining principal balance	$ 4,330,326,000	4,330,326,000					$ 4,020,058,000
Term Loan
Debt Instrument [Line Items]
Term loan facility, accordion feature for additional term loan commitments						$ 100,000,000
Term loan facility, maximum borrowing capacity						$ 650,000,000
Term loan facility, additional borrowing capacity					$ 20,000,000
Unsecured debt, net
Debt Instrument [Line Items]
Remaining principal balance	410,700,000	410,700,000
Unsecured debt, net \| 3.45% Unsecured Senior Notes
Debt Instrument [Line Items]
Unsecured senior note	425,000,000	$ 425,000,000
Repurchases of unsecured debt	$ 14,300,000
Stated interest rate on debt (percent)	3.45%	3.45%
Kilroy Realty L.P.
Debt Instrument [Line Items]
Remaining principal balance	$ 4,330,326,000	$ 4,330,326,000					4,020,058,000
Kilroy Realty L.P. \| Revolving credit facility
Debt Instrument [Line Items]
Term loan facility, maximum borrowing capacity	1,100,000,000	1,100,000,000					1,100,000,000
Kilroy Realty L.P. \| Term Loan Facility \| Unsecured Term Loan Facility
Debt Instrument [Line Items]
Term loan facility, maximum borrowing capacity	520,000,000	520,000,000					$ 400,000,000
Kilroy Realty L.P. \| Mortgages \| Secured Mortgage Loan Transaction
Debt Instrument [Line Items]
Long term debt				$ 375,000,000
Number of office buildings \| office_building				2
Number of apartment units \| apartment_unit				608
Square feet of retail space \| ft²				95,000
Percentage bearing fixed interest rate				5.90%
Kilroy Realty L.P. \| Unsecured debt, net \| Unsecured Term Loan Facility
Debt Instrument [Line Items]
Long term debt	$ 520,000,000	$ 520,000,000