Revenue (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Capitalized Contract Cost [Line Items]
Revenue from Contract with Customer, Duration [Extensible Enumeration]	Long-term Contract with Customer [Member]
Deferred Contract Costs And Capitalized Sales Commissions
Capitalized Contract Cost [Line Items]
Deferred contract costs	$ 80.6	$ 82.3
Capitalized sales commissions to selling, general and administrative expenses
Capitalized Contract Cost [Line Items]
Capitalized contract cost, amortization	12.5	12.2
Other deferred contract costs as a reduction of revenue
Capitalized Contract Cost [Line Items]
Capitalized contract cost, amortization	$ 6.4	$ 6.5