Lease-Up Properties, Maximum Stabilized Occupacy, Percentage

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- Definition

Number of Real Estate Properties Sold

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Area of land held.

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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

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

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- Definition

The number of real estate properties owned as of the balance sheet date.

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No definition available.

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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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Organization and Basis of Presentation (Details Textuals) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2014 USD ($)	Sep. 30, 2015 USD ($) a building property	Sep. 30, 2014 USD ($)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Lease-Up Properties, Maximum Stabilized Occupacy, Percentage		95.00%
Number of buildings \| building		10
Percentage of general partnership interest owned by the company in the Operating Partnership	98.00%	98.10%	97.90%
Percentage of Common limited partnership interest owned by certain non-affiliated investors and certain directors and officers of the Company in the Operating Partnership	2.00%	1.90%	2.10%
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 219,600	$ 180,700
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	23,400	43,500
Noncontrolling Interest in Variable Interest Entity	5,862	6,336
Proceeds from Sale of Real Estate Held-for-investment		$ 319,639	$ 368,381
Number of Real Estate Properties Sold \| property		10
WASHINGTON
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of buildings \| property		12
Kilroy Realty, L.P. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage of limited partnership interest owned by Operating Partnership		99.00%
Proceeds from Sale of Real Estate Held-for-investment		$ 319,639	$ 368,381
Kilroy Realty Finance, Inc. [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		1.00%
Real Estate Investment [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	211,800	$ 176,900
Restricted cash [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Proceeds from Sale of Real Estate Held-for-investment	$ 59,200
Land [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Area of Land \| a		106