Real Estate, Net - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	May 31, 2018	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
REAL ESTATE, NET
Depreciation expense		$ 695,000	$ 695,000	$ 2,100,000	$ 2,100,000
Intangible assets, original valuation		11,100,000		11,100,000		$ 11,100,000
Accumulated amortization				4,000,000.0		$ 3,400,000
Amortization of intangible assets		185,000	$ 185,000	555,000	$ 555,000
Aggregate fees paid by SCA to the Company		46,400,000		46,400,000
Remaining fees to be paid by SCA to the Company		179,000		179,000
SCA
REAL ESTATE, NET
Contract amount for purchase of condominium unit				41,500,000
Construction supervision fee receivable		5,000,000.0		5,000,000.0
Construction costs reimbursed		$ 56,000,000.0		$ 56,000,000.0
237 11th Property
REAL ESTATE, NET
Purchase price of property	$ 81,200,000
Business acquisition, transaction costs	$ 700,000
Percentage of property leased				97.10%