Fair Value Disclosure Fair Value Disclosure - Other Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Recourse debt	$ 12,451.7	$ 8,215.3
Debt Instrument, Fair Value Disclosure	12,313.3	7,861.2
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Recourse Fixed Rate Debt Fair Value Disclosure	8,622.5	7,609.5
Recourse Floating Rate Debt Fair Value Disclosure	3,829.2	605.8
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Recourse Fixed Rate Debt Fair Value Disclosure	8,443.1	7,243.9
Recourse Floating Rate Debt Fair Value Disclosure	$ 3,870.2	$ 617.3