Lease-Up Properties, Maximum Stabilized Occupancy, Duration

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- Definition

Lease-Up Properties, Maximum Stabilized Occupancy, Percentage

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- Definition

Number of Buildings

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- Definition

Number of Future Development Sites

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- Definition

Number of Property Partnerships

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- Definition

Number of Residential Units

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- Definition

Property Ownership Percentage

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- Definition

Area of land held.

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- Definition

Percentage investment held by members or limited partners of 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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Net rentable area for properties owned.

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

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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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Organization and Ownership - Narrative (Details)	12 Months Ended
Organization and Ownership - Narrative (Details)	Dec. 31, 2021 ft² a developmentSite property_partnership residential_unit building property	Dec. 31, 2020
Real Estate Properties [Line Items]
Lease-up properties occupancy percentage	95.00%
Lease-up properties occupancy duration	1 year
Rentable square feet (unaudited) \| ft²	15,456,528
101 First LLC and 303 Second LLC
Real Estate Properties [Line Items]
Ownership interest	56.00%
Redwood LLC
Real Estate Properties [Line Items]
Ownership interest	93.00%
Operating Partnership
Real Estate Properties [Line Items]
Ownership interest (percent)	99.00%	99.00%
Operating Partnership \| Non-Affiliated Investors
Real Estate Properties [Line Items]
Ownership interest (percent)	1.00%	1.00%
San Francisco, California \| 101 First LLC and 303 Second LLC
Real Estate Properties [Line Items]
Number of properties \| building	1
Number of buildings \| building	1
Redwood City, California \| Redwood LLC
Real Estate Properties [Line Items]
Number of properties \| property	2
Number of buildings \| property	2
Development projects
Real Estate Properties [Line Items]
Number of properties	4
Number of buildings	4
Development projects \| San Diego and South San Francisco, California
Real Estate Properties [Line Items]
Rentable square feet (unaudited) \| ft²	1,109,509
Development projects \| Hollywood, California
Real Estate Properties [Line Items]
Number of units \| residential_unit	193
Development project in the tenant improvement phase \| Washington
Real Estate Properties [Line Items]
Number of properties	1
Number of buildings	1
Development project in the tenant improvement phase \| TEXAS
Real Estate Properties [Line Items]
Number of properties	1
Number of buildings	1
Future development project \| Washington
Real Estate Properties [Line Items]
Number of properties	1
Number of buildings	1
Development properties
Real Estate Properties [Line Items]
Number of property partnerships \| property_partnership	3
Development properties \| 101 First LLC and 303 Second LLC
Real Estate Properties [Line Items]
Number of property partnerships \| property_partnership	2
Building \| San Diego and South San Francisco, California
Real Estate Properties [Line Items]
Number of buildings \| property	6
Development sites
Real Estate Properties [Line Items]
Number of future development sites	6
Area of undeveloped land \| a	59
Stabilized Office Properties
Real Estate Properties [Line Items]
Number of buildings \| property	120
Rentable square feet (unaudited) \| ft²	15,456,528
Stabilized Office Properties \| Washington
Real Estate Properties [Line Items]
Number of properties \| property	9
Number of buildings \| property	9
Properties and development projects
Real Estate Properties [Line Items]
Property ownership percentage	100.00%
Office Properties Owned by Consolidated Property Partnerships
Real Estate Properties [Line Items]
Number of properties \| property	4
Number of buildings \| property	4