Commitments and Contingencies (Details) - USD ($) $ in Millions			3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 20, 2024	Aug. 14, 2023	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Judicial ruling
Loss Contingencies [Line Items]
Litigation interest	$ 199.7
Senior Preferred Stock Purchase Agreements Litigation
Loss Contingencies [Line Items]
Awarded damages to Fannie Mae		$ 299.4
Litigation interest rate	5.01%
Other noninterest expense			$ 7.0	$ 20.0	$ 24.0	$ 495.0