Lease-Up Properties, Maximum Stabilized Occupacy, Percentage

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- Definition

Lease-Up Properties, Maximum Stabilized Occupancy, Duration

+ References

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- Definition

Number of Development Projects

+ References

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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

Area of a real estate property.

+ 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://fasb.org/us-gaap/role/ref/legacyRef
-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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ 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 - Narrative (Details)	9 Months Ended	12 Months Ended
Organization and Ownership - Narrative (Details)	Sep. 30, 2019	Dec. 31, 2019 building	Dec. 31, 2019 property	Dec. 31, 2019 ft²	Dec. 31, 2019	Dec. 31, 2019 a	Dec. 31, 2019 property_partnership	Dec. 31, 2019 project	Dec. 31, 2018
Real Estate Properties [Line Items]
Lease-up properties occupancy percentage	95.00%
Lease-up properties occupancy duration	1 year
Ownership interest of noncontrolling interest					1.90%				2.00%
Kilroy Realty Finance, Inc. [Member]
Real Estate Properties [Line Items]
Common general partnership interest in the Finance Partnership (percentage)		1.00%
101 First LLC and 303 Second LLC [Member]
Real Estate Properties [Line Items]
Ownership interest					56.00%
Redwood LLC [Member]
Real Estate Properties [Line Items]
Ownership interest					93.00%
Operating Partnership [Member]
Real Estate Properties [Line Items]
Ownership interest					98.10%				98.00%
Finance Partnership [Member] \| Operating Partnership [Member]
Real Estate Properties [Line Items]
Ownership interest		99.00%
Washington [Member]
Real Estate Properties [Line Items]
Number of properties		1	8
Number of development projects \| project								1
Development properties [Member]
Real Estate Properties [Line Items]
Number of properties							3	2
Area of undeveloped land \| a						61
Development properties [Member] \| 101 First LLC and 303 Second LLC [Member]
Real Estate Properties [Line Items]
Number of properties \| property_partnership							2
Office properties [Member]
Real Estate Properties [Line Items]
Number of properties		112	4
Office properties [Member] \| San Francisco, California [Member] \| 101 First LLC and 303 Second LLC [Member]
Real Estate Properties [Line Items]
Number of properties			1
Office properties [Member] \| Redwood City, California [Member] \| Redwood LLC [Member]
Real Estate Properties [Line Items]
Number of properties			2
Development sites [Member]
Real Estate Properties [Line Items]
Number of properties \| project								5
Properties and development projects [Member]
Real Estate Properties [Line Items]
Property ownership percentage		100.00%
Development Project in San Francisco [Member] \| Development properties [Member] \| San Francisco, California [Member]
Real Estate Properties [Line Items]
Number of properties			1
Development Project in San Francisco [Member] \| Office properties [Member] \| San Francisco, California [Member]
Real Estate Properties [Line Items]
Area of real estate property \| ft²				394,340