Commitments and Contingencies (Details) ft² in Thousands		1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 20, 2023 USD ($)	Jan. 31, 2022 USD ($) renewal_option	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2020 USD ($)	Jul. 31, 2018 USD ($) ft²
Other Commitments
Fair value reset renewal period		25 years
Loss contingency, damages awarded, value					$ 21,350,000
Revenues			$ 450,995,000	$ 457,431,000	1,369,277,000	$ 1,353,055,000
Guarantees and master leases			1,153,000,000		1,153,000,000
Fund clawback payment					26,700,000
Construction commitment			169,500,000		169,500,000
Noncontrolling Interest
Other Commitments
Loss contingency, damages awarded, value					6,405,000
Rental revenues
Other Commitments
Revenues			$ 400,367,000	$ 409,144,000	$ 1,215,994,000	$ 1,211,621,000
Joint Venture | Farley Office and Retail
Other Commitments
Equity method ownership percentage			95.00%		95.00%
Capital contributions			$ 92,400,000		$ 92,400,000		$ 92,400,000
Affiliated Entity | Farley Office and Retail
Other Commitments
Equity method ownership percentage			5.00%		5.00%
Unsecured revolving credit facilities
Other Commitments
Outstanding letters of credit			$ 30,233,000		$ 30,233,000
Regus PLC
Other Commitments
Loss contingency, damages awarded, value					21,350,000
Regus PLC | Noncontrolling Interest
Other Commitments
Loss contingency, damages awarded, value					6,405,000
PENN 1
Other Commitments
Number of renewal options | renewal_option		3
Term of contract		25 years
Finance lease liability		$ 350,000,000
Finance lease, right-of-use asset		$ 350,000,000
345 Montgomery Street | Subsidiary of Regus PLC
Other Commitments
Square footage of real estate property (in sqft) | ft²								78
Lessor, operating lease, lease not yet commenced, term of contract								15 years
Regus PLC | 345 Montgomery Street
Other Commitments
Guarantor obligations, maximum exposure, undiscounted								$ 90,000,000
General Liability
Insurance
Insurance limit per occurrence			300,000,000		300,000,000
Insurance limit per property			300,000,000		300,000,000
Disease Coverage
Insurance
Insurance limit per property			275,000,000		275,000,000
Insurance maximum coverage per incident	$ 250,000,000
All Risk And Rental Value
Insurance
Insurance limit per occurrence			2,000,000,000		2,000,000,000
Earthquake California Properties
Insurance
Insurance limit per occurrence			$ 350,000,000		$ 350,000,000
Vornado deductible, percentage of property value			5.00%		5.00%
Insurance maximum coverage limit in aggregate			$ 350,000,000		$ 350,000,000
Terrorism Acts
Insurance
Insurance limit per occurrence			6,000,000,000		6,000,000,000
Insurance maximum coverage limit in aggregate			6,000,000,000		6,000,000,000
Non-Certified Acts of Terrorism
Insurance
Insurance maximum coverage limit in aggregate			1,200,000,000		1,200,000,000
NBCR Acts
Insurance
Insurance limit per occurrence			5,000,000,000		5,000,000,000
Insurance maximum coverage limit in aggregate			5,000,000,000		5,000,000,000
NBCR Acts | PPIC
Insurance
Insurance deductible			$ 1,774,525		$ 1,774,525
Insurance deductible percentage of balance of covered loss			20.00%		20.00%