Mortgage Notes Payable, Net - Mortgage Notes (Details) $ in Thousands		3 Months Ended
	Apr. 29, 2024	Dec. 31, 2024 USD ($) property	Sep. 30, 2024	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Mortgage notes payable, gross		$ 350,000
Mortgage notes payable, net		$ 347,384		$ 395,702
Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		6
Mortgage notes payable, gross		$ 350,000		399,500
Effective Interest Rate		4.43%
Less: deferred financing costs, net		$ (2,616)		(3,798)
Mortgage notes payable, net		347,384		395,702
9 Times Square
Debt Instrument [Line Items]
Contracted sale price		$ 63,500
9 Times Square | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		0
Mortgage notes payable, gross		$ 0		49,500
Effective Interest Rate		6.41%	3.72%
Variable rate	2.60%
1140 Avenue of the Americas | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		1
Mortgage notes payable, gross		$ 99,000		99,000
Effective Interest Rate		4.18%
123 William Street | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		1
Mortgage notes payable, gross		$ 140,000		140,000
Effective Interest Rate		4.74%
400 E. 67th Street - Laurel Condominium/200 Riverside Boulevard - ICON Garage (2) | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		2
Mortgage notes payable, gross		$ 50,000		50,000
Effective Interest Rate		4.59%
8713 Fifth Avenue | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		1
Mortgage notes payable, gross		$ 10,000		10,000
Effective Interest Rate		5.05%
196 Orchard Street | Mortgages
Debt Instrument [Line Items]
Encumbered Properties | property		1
Mortgage notes payable, gross		$ 51,000		$ 51,000
Effective Interest Rate		3.85%