Revenue Recognition - Contract Balances (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Contract with Customer, Asset and Liability [Abstract]
Total contract liabilities	$ 8.1	$ 9.0
Contract liabilities, revenue recognition period	36 months
Capitalized Contract Cost [Abstract]
Deferred sales commissions	$ 6.5	$ 7.5
Minimum
Capitalized Contract Cost [Abstract]
Sales commissions capitalized, amortization period	4 years
Maximum
Capitalized Contract Cost [Abstract]
Sales commissions capitalized, amortization period	5 years