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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 835
-SubTopic 30
-Section 55
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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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-Name Accounting Standards Codification
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-Section S99
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Details

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Subsequent Events (Details) - USD ($)		9 Months Ended
Subsequent Events (Details) - USD ($)	Oct. 17, 2018	Sep. 30, 2018	Sep. 30, 2017	Oct. 26, 2018	Oct. 22, 2018	May 11, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Payment of dividend		$ 132,639,000	$ 297,993,000
Outstanding borrowings		330,000,000					$ 0
Subsequent event [Member]
Subsequent Event [Line Items]
Payment of dividend	$ 47,400,000
Kilroy Realty L.P. [Member]
Subsequent Event [Line Items]
Payment of dividend		132,639,000	$ 297,993,000
Outstanding borrowings		330,000,000					0
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.35% Series B Senior Note [Member]
Subsequent Event [Line Items]
Debt, principal		0
Stated coupon rate						4.35%
Kilroy Realty L.P. [Member] \| Unsecured debt [Member] \| 4.35% Series B Senior Note [Member] \| Subsequent event [Member]
Subsequent Event [Line Items]
Debt, principal					$ 200,000,000.0
Stated coupon rate					4.35%
Kilroy Realty L.P. [Member] \| Revolving credit facility [Member]
Subsequent Event [Line Items]
Outstanding borrowings		$ 330,000,000					$ 0
Kilroy Realty L.P. [Member] \| Revolving credit facility [Member] \| Subsequent event [Member]
Subsequent Event [Line Items]
Outstanding borrowings				$ 165,000,000.0