Revenue - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred revenue contract liability	$ 73.0	$ 71.8
Revenue recognized from deferred	37.7
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue, remaining performance obligation, amount	$ 43.7
Revenue, remaining performance obligation, expected timing of satisfaction, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue, remaining performance obligation, amount	$ 29.3
Revenue, remaining performance obligation, expected timing of satisfaction, period	5 years
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Threshold period past due when Company ceases billing and accruing late fees	30 days
Capitalized contract cost amortization period (in years)	5 years
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Threshold period past due when Company ceases billing and accruing late fees	40 days
Capitalized contract cost amortization period (in years)	10 years
Sales Revenue, Net | Contracts with Customers
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk, percentage (more than)	75.00%
Prepaid Expenses
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost	$ 15.1	14.8
Other Assets
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost	37.2	39.7
Selling Expense
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost amortization	15.3	14.3	$ 12.0
Processing Expense
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cost of equipment sales	$ 65.5	$ 76.4	$ 83.9