Operating Partnership, Payment Percent

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- Definition

Operating Partnership, Total Payment Percentage

+ References

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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

Amount, after accumulated amortization, of debt discount.

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- Definition

Gross amount of debt extinguished.

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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, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of 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, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Nov. 30, 2018
Debt Instrument [Line Items]
Debt issuance discount		$ (6,500,000)
Loss on early extinguishment of debt (Note 9)		0	$ 12,623,000	$ 5,312,000
Unsecured debt [Member]
Debt Instrument [Line Items]
Long-term debt	$ 2,600,000,000	3,300,000,000	2,600,000,000
Kilroy Realty L.P. [Member]
Debt Instrument [Line Items]
Loss on early extinguishment of debt (Note 9)		$ 0	12,623,000	$ 5,312,000
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 3.050% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount					$ 500,000,000.0	$ 400,000,000.0
Debt issuance discount					$ (600,000)
Stated interest rate		3.05%			3.05%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.750% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	$ 400,000,000.0		$ 400,000,000.0
Debt issuance discount						$ (1,500,000)
Stated interest rate	4.75%		4.75%			4.75%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 6.625% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	$ 250,000,000.0		$ 250,000,000.0
Stated interest rate	6.625%		6.625%
Loss on early extinguishment of debt (Note 9)	$ 12,600,000
Extinguishment of debt	11,800,000
Write off of unamortized discount and deferred financing costs	$ 800,000
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.300% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount		$ 50,000,000.0
Stated interest rate		4.30%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.350% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount		$ 200,000,000.0
Stated interest rate		4.35%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| Series A Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount		$ 50,000,000.0
Long-term debt		50,000,000
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| Series B Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount		200,000,000.0
Long-term debt		$ 200,000,000
Kilroy Realty L.P. [Member] \| Private placement [Member] \| Unsecured debt [Member] \| Series A and B Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Operating partnership, payment percent		5.00%
Operating partnership, total payment percentage		100.00%