Segments - Schedule of NOI for Each Reportable Segment Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Property-related revenues		$ 721,191	$ 711,956	$ 698,313
Property-related operating expenses		(293,965)	(277,422)	(265,438)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		37,360	45,141	43,597
NOI	[1]	464,586	479,675	476,472
New York [Member]
Segment Reporting Information [Line Items]
Property-related revenues		460,715	468,409	443,384
Property-related operating expenses		(204,301)	(199,085)	(191,793)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		12,880	13,257	11,303
NOI	[1]	269,294	282,581	262,894
San Francisco [Member]
Segment Reporting Information [Line Items]
Property-related revenues		261,954	245,560	258,188
Property-related operating expenses		(87,478)	(74,396)	(69,976)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		24,347	31,596	32,221
NOI	[1]	198,823	202,760	220,433
Other [Member]
Segment Reporting Information [Line Items]
Property-related revenues		(1,478)	(2,013)	(3,259)
Property-related operating expenses		(2,186)	(3,941)	(3,669)
NOI from unconsolidated joint ventures (excluding One Steuart Lane)		133	288	73
NOI	[1]	$ (3,531)	$ (5,666)	$ (6,855)

[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.