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Debt Obligations, net - (Secured Term Loan and Credit Facility Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 09, 2026	Oct. 08, 2026	Sep. 29, 2026	Mar. 31, 2023	Oct. 31, 2026	Dec. 31, 2023	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Line of Credit Facility
Stock repurchase program, authorized amount			$ 10,000				$ 10,000		$ 10,000
Safe Credit Facility \| Safehold Inc. \| Interest expense
Line of Credit Facility
Interest expense							2,400	$ 2,400	7,100	$ 7,100
Margin Loan Facility
Line of Credit Facility
Repayment of principal							48,000		48,000
Long-term debt, outstanding balance							46,500		46,500
Secured Debt
Line of Credit Facility
Long-term debt, outstanding balance							$ 161,524		$ 161,524		$ 270,357
Secured Debt \| Safe Credit Facility
Line of Credit Facility
Stated interest rate							8.00%		8.00%		8.00%
Long-term debt, outstanding balance							$ 115,000		$ 115,000		$ 115,000
Secured Debt \| Safe Credit Facility \| Safehold Inc.
Line of Credit Facility
Stated interest rate				8.00%
Interest rate when any loan remains outstanding under an incremental facility available under the Safe Credit Facility				10.00%
Extension fee percentage			0.50%
Increase in interest rate of outstanding borrowings			1.00%
Maximum voluntary prepayments			$ 50,000
Prepayments paid on margin loan facility			$ 40,000
Secured Debt \| Safe Credit Facility \| Safehold Inc. \| Subsequent Events
Line of Credit Facility
Maturity extension fee					$ 2,400
Secured Debt \| Term Loan \| Safehold Inc.
Line of Credit Facility
Debt instrument, face amount				$ 115,000
Secured Debt \| Incremental Borrowing Facility \| Safehold Inc.
Line of Credit Facility
Maximum borrowing capacity				25,000
Secured Debt \| Margin Loan Facility
Line of Credit Facility
Long-term debt, outstanding balance							$ 46,524		$ 46,524		$ 91,087
Basis point spread on variable interest rate									3.50%		3.50%
Secured Debt \| Margin Loan Facility \| Subsequent Events
Line of Credit Facility
Mandatory prepayment, Stock price trigger	$ 8	$ 10
Delayed draw commitment termination amount	$ 15,800
Secured Debt \| Margin Loan Facility \| Morgan Stanley
Line of Credit Facility
Debt instrument, face amount				$ 140,000
Debt instrument term				3 years
Secured Debt \| Senior Construction Mortgage Loan
Line of Credit Facility
Long-term debt, outstanding balance											$ 64,270
Secured Debt \| Senior Construction Mortgage Loan \| Venture
Line of Credit Facility
Debt instrument, face amount						$ 80,000
Debt Instrument, Variable Interest Rate, Type						us-gaap:SecuredOvernightFinancingRateSofrMember
Basis point spread on variable interest rate						6.85%
Debt instrument floor rate						3.65%
Debt instrument origination fees						1.00%
Debt instrument exit fees						1.85%