Other Income (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Other Income	$ 66.9	$ 83.4	$ 53.1
Ancillary Product Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Other Income	34.1	60.6	40.2
Interest Income [Member]
Disaggregation of Revenue [Line Items]
Other Income	19.7	6.6	1.2
Remarketing Fees [Member]
Disaggregation of Revenue [Line Items]
Other Income	10.7	13.4	7.8
Other [Member]
Disaggregation of Revenue [Line Items]
Other Income	2.4	$ 2.8	$ 3.9
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Other Income	54.7
Transferred over Time [Member] | Ancillary Product Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Other Income	34.1
Transferred over Time [Member] | Interest Income [Member]
Disaggregation of Revenue [Line Items]
Other Income	19.7
Transferred over Time [Member] | Remarketing Fees [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Transferred over Time [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.9
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Other Income	12.2
Transferred at Point in Time [Member] | Ancillary Product Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Transferred at Point in Time [Member] | Interest Income [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Transferred at Point in Time [Member] | Remarketing Fees [Member]
Disaggregation of Revenue [Line Items]
Other Income	10.7
Transferred at Point in Time [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Other Income	1.5
Third Party Providers [Member]
Disaggregation of Revenue [Line Items]
Other Income	53.9
Third Party Providers [Member] | Ancillary Product Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Other Income	34.1
Third Party Providers [Member] | Interest Income [Member]
Disaggregation of Revenue [Line Items]
Other Income	19.7
Third Party Providers [Member] | Remarketing Fees [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Third Party Providers [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.1
Dealers [Member]
Disaggregation of Revenue [Line Items]
Other Income	13.0
Dealers [Member] | Ancillary Product Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Dealers [Member] | Interest Income [Member]
Disaggregation of Revenue [Line Items]
Other Income	0.0
Dealers [Member] | Remarketing Fees [Member]
Disaggregation of Revenue [Line Items]
Other Income	10.7
Dealers [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Other Income	$ 2.3