Leases - Additional Information (Details)			3 Months Ended		9 Months Ended
Leases - Additional Information (Details)	Jul. 28, 2025 USD ($)	May 01, 2024 USD ($)	Sep. 30, 2025 USD ($) Property	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) Property	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Number of properties subject to ground lease \| Property			1		1
ROU assets			$ 10,300,000		$ 10,300,000		$ 11,500,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]			Prepaid Expense and Other Assets		Prepaid Expense and Other Assets		Prepaid Expense and Other Assets
Outstanding lease liabilities			$ 600,000		$ 600,000		$ 1,200,000
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]			Accounts Payable and Accrued Liabilities		Accounts Payable and Accrued Liabilities		Accounts Payable and Accrued Liabilities
Expected cash payments on operating leases for the remainder of 2025			$ 67,600		$ 67,600
Expected cash payments on operating leases in 2026			200,000		200,000
Expected cash payments on operating leases in 2027			45,000		45,000
Expected cash payments on operating leases in 2028			45,000		45,000
Expected cash payments on operating leases in 2029			45,000		45,000
Expected cash payments on operating leases in 2030			45,000		45,000
Expected cash payments on operating leases, thereafter			1,900,000		1,900,000
Present value discount			(600,000)		$ (600,000)
Operating leases expiration year					2073
Payment to terminate lease		$ 1,600,000
Office space cost	$ 19,000
Operating lease extend term	1 year
Initial lease end date		Aug. 30, 2028
Revised lease end date		Jul. 31, 2025
Reduction in initial lease term		37 months
General and Administrative Expenses [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Rent expense			200,000	$ 500,000	$ 1,100,000	$ 1,300,000
Property Operating Expense [Member]
Schedule Of Operating Leases Future Minimum Payments Receivable [Line Items]
Rent expense			$ 11,200	$ 33,700	$ 11,200	$ 33,700

Seritage Growth Properties 10-Q