Fair Value Disclosure (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	$ 5.3	$ (4.0)	$ (10.1)
Other Nonoperating Income (Expense) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	3.7	(5.7)	(12.0)
Carrying Amount [Member]
Liabilities
Recourse fixed rate debt	7,026.6	6,045.1
Recourse floating rate debt	361.5	417.8
Estimate of Fair Value Measurement [Member]
Liabilities
Recourse fixed rate debt	6,614.6	5,309.8
Recourse floating rate debt	362.9	417.0
Interest Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	$ 1.6	$ 1.7	$ 1.9