Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	$ 59.0	$ 54.5
Cost of additions reduced by recognition of tax credits	1.4	1.1	$ 2.2
Capitalized cost of software under development	1.6	$ 0.4	$ 0.3
Trade names and trademarks
Finite-Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	$ 50.1