Lease-Up Properties, Maximum Stabilized Occupacy, Percentage

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- Definition

Property Ownership Percentage

+ References

No definition available.

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- Definition

Area of land held.

+ References

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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

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Net rentable area for properties owned.

+ References

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- Definition

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

+ References

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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.

+ References

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Organization and Ownership (Details Textuals)	12 Months Ended
Organization and Ownership (Details Textuals)	Dec. 31, 2017	Dec. 31, 2017 ft²	Dec. 31, 2017 project	Dec. 31, 2017 building	Dec. 31, 2017 a	Dec. 31, 2017 property	Mar. 31, 2017 ft²	Dec. 31, 2016
Real Estate Properties [Line Items]
Stabilized occupancy	95.00%
Rentable Square Feet (unaudited)		13,720,597
Percentage of general partnership interest owned by the company in the Operating Partnership	97.90%							97.50%
Ownership interest of noncontrolling interest	2.10%							2.50%
Kilroy Realty, L.P. [Member]
Real Estate Properties [Line Items]
Percentage of limited partnership interest owned by Operating Partnership	99.00%
101 First LLC and 303 Second LLC [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership	56.00%
Redwood LLC [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by the company in the Operating Partnership	93.00%
Kilroy Realty Finance, Inc. [Member]
Real Estate Properties [Line Items]
Percentage of general partnership interest owned by wholly-owned subsidiary of the Company	1.00%
Washington [Member]
Real Estate Properties [Line Items]
Number of buildings \| property						12
Washington - land parcel [Member]
Real Estate Properties [Line Items]
Number of buildings \| building				1
Development properties [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)		1,800,000
Number of buildings			4			3
Development properties [Member] \| Hollywood, California [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)							365,359
Development sites [Member]
Real Estate Properties [Line Items]
Number of buildings \| project			6
Office properties [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)		13,720,597
Number of buildings				101		4
Area of land \| a					48
Properties and Development Projects [Member]
Real Estate Properties [Line Items]
Property Ownership Percentage	100.00%