Other income (Schedule of Other Income) (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