Lease-Up Properties, Maximum Stabilized Occupacy, Percentage

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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

+ Details

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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.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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).

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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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- Definition

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

+ References

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Organization and Basis of Presentation (Details Textuals) (USD $)	9 Months Ended				9 Months Ended					12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014 WASHINGTON building	Sep. 30, 2014 Kilroy Realty, L.P. [Member]	Sep. 30, 2013 Kilroy Realty, L.P. [Member]	Sep. 30, 2014 Kilroy Realty Finance, Inc. [Member]	Sep. 30, 2014 Real Estate Investment [Member]	Dec. 31, 2013 Real Estate Investment [Member]	Dec. 31, 2013 Restricted cash [Member]
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				13
Percentage of general partnership interest owned by the company in the Operating Partnership	97.90%	97.80%	97.80%
Percentage of Common limited partnership interest owned by certain non-affiliated investors and certain directors and officers of the Company in the Operating Partnership	2.10%	2.20%	2.20%
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest							1.00%
Percentage of limited partnership interest owned by Operating Partnership					99.00%
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 98,500,000		$ 251,800,000					$ 98,100,000	$ 234,500,000
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	20,100,000		12,100,000
Noncontrolling Interest in Variable Interest Entity	5,222,000		4,885,000
Proceeds from Sale of Real Estate Held-for-investment	$ 368,381,000	$ 14,409,000			$ 368,381,000	$ 14,409,000				$ 32,200,000