Secured and Unsecured Debt of the Operating Partnership - Debt Maturities (Details) - Kilroy Realty, L.P. [Member] $ in Thousands	Jun. 30, 2017 USD ($)
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Remaining 2017	$ 3,072
2018	451,669
2019	265,309
2020	255,137
2021	5,342
Thereafter	1,599,023
Total debt	2,579,552
Unamortized debt issuance costs	(12,000)
Unsecured Senior Notes [Member]
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Unamortized discount	(6,200)
Secured debt [Member]
Stated debt maturities and scheduled amortization payments, excluding debt discounts
Unamortized premium	$ 3,500

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt premium.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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