Mortgages and Other Loans Payable - Schedule of Mortgages and Other Loans Payable (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Total fixed rate debt	$ 1,667,249	$ 1,587,474
Total floating rate debt	376,153	363,550
Total mortgages and other loans payable	2,043,402	1,951,024
Deferred financing costs, net of amortization	(7,580)	(6,389)
Total mortgages and other loans payable, net	2,035,822	1,944,635
100 Church Street
Debt Instrument [Line Items]
Total fixed rate debt	370,000	370,000
7 Dey / 185 Broadway
Debt Instrument [Line Items]
Total fixed rate debt	190,149	190,148
10 East 53rd Street
Debt Instrument [Line Items]
Total fixed rate debt	204,775	205,000
Landmark Square
Debt Instrument [Line Items]
Total fixed rate debt	100,000	100,000
485 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt	450,000	450,000
500 Park Avenue
Debt Instrument [Line Items]
Total fixed rate debt	80,000	0
420 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt	272,325	272,326
100 Park Avenue
Debt Instrument [Line Items]
Total floating rate debt	376,153	360,000
CMBS Repurchase Facility
Debt Instrument [Line Items]
Total floating rate debt	$ 0	$ 3,550
Weighted Average | 100 Church Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.89%
Weighted Average | 7 Dey / 185 Broadway
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	6.65%
Weighted Average | 10 East 53rd Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.37%
Weighted Average | Landmark Square
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.90%
Weighted Average | 485 Lexington Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.25%
Weighted Average | 500 Park Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	6.57%
Weighted Average | 420 Lexington Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	8.24%
Weighted Average | 100 Park Avenue
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	2.37%