Loans and Allowance for Credit Losses - Additional Information (Details) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan
Mortgages receivable, net
Number of loans held for investment \| loan	119	157
Direct reserves	$ 5.5	$ 13.3
Number of loans held for sale \| loan	7	11
Loans held for sale	$ 9.4	$ 15.9
Aggregate valuation allowance	0.6	4.9
Loans on nonaccrual status	$ 104.1	87.1
Default interest rate on mortgage loans	18.00%
Outstanding mortgage loan portfolio	$ 50.4	55.0
Carrying Value	$ 6.8
Number of loans modified experience difficulty \| loan	13
Aggregate outstanding balance	$ 30.4
Loans defaulted during period \| loan	1
Deferred loan fee revenue	$ 2.4	2.0
Deferred fees for loans held for sale	$ 0.0	$ 0.0
Mortgage Concentration Risk \| Revenue Benchmark \| One borrower
Mortgages receivable, net
Loans outstanding (in percent)	13.40%	14.00%
Minimum
Mortgages receivable, net
Interest rate (as a percent)	7.00%
Maximum
Mortgages receivable, net
Interest rate (as a percent)	15.00%

Amount principal outstanding of direct reserve on loan portfolio.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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