Lease-Up Properties, Maximum Stabilized Occupacy, Percentage

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- Definition

Property Ownership Percentage

+ References

No definition available.

+ Details

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- Definition

Area of land held.

+ References

No definition available.

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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.

+ References

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- Definition

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

+ References

No definition available.

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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

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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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

No definition available.

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Organization and Ownership (Details Textuals)	12 Months Ended
Organization and Ownership (Details Textuals)	Dec. 31, 2016	Dec. 31, 2016 ft²	Dec. 31, 2016 project	Dec. 31, 2016 building	Dec. 31, 2016 a	Dec. 31, 2016 property	Dec. 31, 2015	Jan. 31, 2014 ft²
Real Estate Properties [Line Items]
Stabilized occupancy	95.00%
Rentable Square Feet (unaudited)		14,025,856						79,000
Percentage of general partnership interest owned by the company in the Operating Partnership	97.50%						98.10%
Ownership interest of noncontrolling interest	2.50%						1.90%
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%
Kilroy Realty, L.P. [Member]
Real Estate Properties [Line Items]
Percentage of limited partnership interest owned by Operating Partnership	99.00%
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]
Number of Buildings			3			3
Rentable Square Feet (unaudited)		1,100,000
Development properties [Member] \| San Francisco, California [Member]
Real Estate Properties [Line Items]
Number of Buildings \| building				2
Rentable Square Feet (unaudited)		640,942
Development properties [Member] \| Del Mar, California [Member]
Real Estate Properties [Line Items]
Rentable Square Feet (unaudited)		73,000
Development Sites [Member]
Real Estate Properties [Line Items]
Number of Buildings \| project			7
Office properties [Member]
Real Estate Properties [Line Items]
Number of Buildings				108		4
Rentable Square Feet (unaudited)		14,025,856
Area of land \| a					54
Properties and Development Projects [Member]
Real Estate Properties [Line Items]
Property Ownership Percentage	100.00%