Organization, Ownership and Basis of Presentation - Narrative (Details) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($) ft² a property VIE property_partnership development_site building	Sep. 30, 2021	Dec. 31, 2021 USD ($) VIE
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Lease-up properties occupancy percentage	95.00%
Lease-up properties occupancy duration	1 year
Assets | $	$ 10,619,992		$ 10,583,397
Liabilities | $	4,940,215		4,893,527
Noncontrolling interest in VIE | $	$ 186,907		$ 196,064
Variable Interest Entity, Primary Beneficiary
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of VIEs | VIE	2		2
Assets | $	$ 440,400		$ 462,300
Liabilities | $	27,700		28,100
Variable Interest Entity, Primary Beneficiary | Real Estate Investment
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Assets | $	$ 366,100		377,900
San Francisco, California
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | building	1
101 First LLC and 303 Second LLC
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Company owned general partnership interest	56.00%
101 First LLC and 303 Second LLC | Variable Interest Entity, Primary Beneficiary
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Noncontrolling interest in VIE | $	$ 181,800		$ 190,700
Redwood LLC
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Company owned general partnership interest	93.00%
Redwood LLC | Redwood City, California
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | property	2
Operating Partnership
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Ownership interest (percent)	99.00%	99.00%	99.00%
Operating Partnership | Non-Affiliated Investors
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Ownership interest (percent)	1.00%	1.00%	1.00%
Development sites
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of future development sites | development_site	8
Future Development Site
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Area of undeveloped land | a	64
Stabilized Office Properties
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of buildings | property	120
Rentable square feet | ft²	16,248,802
Stabilized Office Properties | Washington
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | property	10
Stabilized Development Projects | Seattle, Washington and San Diego, CA
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of development projects added during the period | property	2
Stabilized Redevelopment Projects | San Diego, CA
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of buildings redevelopment projects added during the period | property	2
Stabilized Office and Life Science Space | Seattle, Washington and San Diego, CA
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of buildings | property	4
Rentable square feet | ft²	1,114,704
Development Project In The Tenant Improvement Phase | Texas
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | development_site	1
Future Development Project | Washington
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | development_site	1
Future Development Project | Texas
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | development_site	1
Properties and development projects
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Property ownership percentage	100.00%
Office properties owned by consolidated property partnerships
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of properties | property	4
Consolidated Property Partnerships
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of property partnerships | property_partnership	3
Consolidated Property Partnerships Owning Office Properties Through REITs | 101 First LLC and 303 Second LLC
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of property partnerships | property_partnership	2