Subsequent Events (Details) $ in Thousands												12 Months Ended
	Feb. 09, 2026 USD ($) ft²	Feb. 04, 2026 USD ($)	Feb. 02, 2026 USD ($)	Feb. 01, 2026 USD ($)	Jan. 26, 2026 USD ($)	Jan. 25, 2026 USD ($)	Jan. 23, 2026 USD ($) ft²	Jan. 22, 2026 USD ($)	Jan. 14, 2026 USD ($)	Jan. 07, 2026 USD ($) ft² credit_facility transaction	Jan. 06, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Subsequent Event [Line Items]
Net proceeds from sale of real estate												$ 37,374	$ 31,605	$ 24,484
Repayments of long-term debt												1,903,513	97,439	$ 148,000
Loans payable												$ 4,920,669	5,676,014
7 West 34th Street
Subsequent Event [Line Items]
Equity method ownership percentage												53.00%
Mortgages Payable
Subsequent Event [Line Items]
Interest rate, effective percentage (in percent)												5.25%
Loans payable												$ 4,920,669	$ 5,676,014
Subsequent Event
Subsequent Event [Line Items]
Number of revolving credit facilities | credit_facility										2
Subsequent Event | 825 Seventh Avenue Office Condominium
Subsequent Event [Line Items]
Equity method ownership percentage					50.00%
Extension term					9 months
Subsequent Event | 61 Ninth Avenue | JV
Subsequent Event [Line Items]
Equity method ownership percentage			45.10%
Extension term			7 months
Subsequent Event | Office And Retail Building | 7 West 34th Street
Subsequent Event [Line Items]
Stated rate (as a percent)							16.00%
Repayments of long-term debt							$ 25,000
Equity method ownership percentage							53.00%
Subsequent Event | Office And Retail Building | 7 West 34th Street | Non-recourse
Subsequent Event [Line Items]
Square footage of real estate property (in sqft) | ft²							477,000
Repayments of long-term debt							$ 50,000
Loans payable							$ 250,000
Subsequent Event | Mortgages Payable | 825 Seventh Avenue Office Condominium
Subsequent Event [Line Items]
Debt amount					$ 48,000	$ 54,000
Repayments of long-term debt						$ 6,000
Subsequent Event | Mortgages Payable | 61 Ninth Avenue
Subsequent Event [Line Items]
Debt amount			$ 155,000	$ 167,500
Repayments of long-term debt				$ 12,500
Subsequent Event | Revolving Credit Facility, 2031
Subsequent Event [Line Items]
Maximum borrowing capacity		$ 1,130,000
Basis spread on variable rate		1.05%
Facility fee (as a percent)		0.25%
Debt amount										$ 1,105,000
Subsequent Event | Unsecured Revolving Credit Facility, Maturing December 2027
Subsequent Event [Line Items]
Maximum borrowing capacity		$ 1,250,000
Subsequent Event | Revolving Credit Facility Maturing April 2029
Subsequent Event [Line Items]
Maximum borrowing capacity										$ 1,000,000	$ 915,000
Basis spread on variable rate										1.16%
Facility fee (as a percent)										0.24%
Subsequent Event | Unsecured term loan
Subsequent Event [Line Items]
Basis spread on variable rate										1.20%	1.25%
Debt amount										$ 850,000	$ 800,000
Subsequent Event | Senior Unsecured Notes Due 2033 | Unsecured term loan
Subsequent Event [Line Items]
Debt amount									$ 500,000
Stated rate (as a percent)									5.75%
Face amount, percent									99.824%
Interest rate, effective percentage (in percent)									5.78%
Net proceeds from sale of real estate									$ 494,000
Repayments of long-term debt									$ 400,000
Subsequent Event | Mortgage, 7 West 34th Street | Office And Retail Building | 7 West 34th Street | Non-recourse
Subsequent Event [Line Items]
Basis spread on variable rate								3.65%
Stated rate (as a percent)							5.79%
Debt term							5 years
Loans payable								$ 300,000
Subsequent Event | Non-Recourse Loan Due 2026 | 825 Seventh Avenue Office Condominium
Subsequent Event [Line Items]
Basis spread on variable rate					2.75%
Extension term			15 months
Subsequent Event | Non-Recourse Loan Due 2026 | 61 Ninth Avenue
Subsequent Event [Line Items]
Basis spread on variable rate			2.45%
Extension term			3 months
Subsequent Event | One Park Avenue Mortgage Loan | Mortgages Payable
Subsequent Event [Line Items]
Basis spread on variable rate	1.78%
Debt term	5 years
Subsequent Event | One Park Avenue Mortgage Loan due March 2026 | Mortgages Payable
Subsequent Event [Line Items]
Basis spread on variable rate	1.22%
3 East 54th Street | Subsequent Event
Subsequent Event [Line Items]
Square footage of real estate property (in sqft) | ft²										18,400
Acquisition costs										$ 141,000
Number of transactions | transaction										2
Loan balance										$ 107,000
Loan balance applied										$ 107,000
Area of real estate property | ft²										232,500
One Park Avenue | Subsequent Event
Subsequent Event [Line Items]
Square footage of real estate property (in sqft) | ft²	945,000
Loan balance	$ 525,000