Write-off of Debt Issuance Costs and Debt Discounts

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Topic 210
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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.

+ References

No definition available.

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- Definition

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

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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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 - Unsecured Senior Notes - Registered Offerings and Private Placement (Details) - USD ($)	1 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 31, 2020	Apr. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Proceeds from issuance of unsecured debt		$ 772,297,000	$ 499,390,000	$ 648,537,000
Loss on early extinguishment of debt (Note 9)		0	0	12,623,000
Unsecured debt [Member]
Debt Instrument [Line Items]
Unamortized discount (premium), net		(8,300,000)	(6,500,000)
Kilroy Realty L.P. [Member]
Debt Instrument [Line Items]
Proceeds from issuance of unsecured debt		772,297,000	499,390,000	648,537,000
Loss on early extinguishment of debt (Note 9)		$ 0	$ 0	$ 12,623,000
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 2.500% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount					$ 425,000,000.0
Unamortized discount (premium), net					$ (2,700,000)
Stated interest rate		2.50%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 3.050% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount							$ 500,000,000.0
Unamortized discount (premium), net							$ (600,000)
Stated interest rate		3.05%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.750% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate		4.75%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 6.625% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate	6.625%			6.625%
Extinguishment of debt	$ 250,000,000.0
Loss on early extinguishment of debt (Note 9)	12,600,000
Premium paid to the note holders at the redemption date	11,800,000
Write-off of unamortized discount and unamortized deferred financing costs	$ 800,000
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.270% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount						$ 350,000,000.0
Stated interest rate		4.27%