Segments - Schedule of NOI for Each Reportable Segment Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022		Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Property-related revenues		$ 711,956		$ 698,313	$ 700,410
Property-related operating expenses		(277,422)		(265,438)	(273,440)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		45,141		43,597	48,631
NOI	[1]	479,675		476,472	475,601
New York [Member]
Segment Reporting Information [Line Items]
Property-related revenues		468,409		443,384	454,071
Property-related operating expenses		(199,085)		(191,793)	(194,648)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		13,257		11,303	11,540
NOI	[1]	282,581		262,894	270,963
San Francisco [Member]
Segment Reporting Information [Line Items]
Property-related revenues		245,560		258,188	234,893
Property-related operating expenses		(74,396)		(69,976)	(68,924)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		31,596		32,221	38,892
NOI	[1]	202,760		220,433	204,861
Other [Member]
Segment Reporting Information [Line Items]
Property-related revenues		2,013		(3,259)	11,446	[2]
Property-related operating expenses		(3,941)		(3,669)	(9,868)	[2]
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		288		73	(1,801)	[2]
NOI	[1]	$ 5,666	[2]	$ (6,855)	$ (223)	[2]

[1] NOI is used to measure the operating performance of our properties. NOI consists of rental revenue (which includes property rentals, tenant reimbursements and lease termination income) and certain other property-related revenue less operating expenses (which includes property-related expenses such as cleaning, security, repairs and maintenance, utilities, property administration and real estate taxes). We use NOI internally as a performance measure and believe it provides useful information to investors regarding our financial condition and results of operations because it reflects only those income and expense items that are incurred at the property level. Other real estate companies may use different methodologies for calculating NOI and, accordingly, our presentation of NOI may not be comparable to other real estate companies.

[2] NOI for the year ended December 31, 2020 includes NOI from discontinued operations. See Note 3, Discontinued Operations.