Other Current Assets (Schedule of Other Current Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Advances against auction contracts	$ 21.9	$ 8.9
Assets held for sale	0.0	0.3
Inventory deposits	16.5	10.3
Prepaid expenses and deposits	52.5	28.7
Derivative financial assets (Note 12)	0.3	0.1
Other current assets	$ 91.2	$ 48.3