Revenues - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
ASU 2016-02
Revenue Recognition [Line Items]
Lease receivables	$ 26.3	$ 26.3	$ 45.5
ASC 2014-09
Revenue Recognition [Line Items]
Receivables from contracts with customers	60.4	60.4	$ 57.1
Revenue recognized that was included in the contract liability	0.8	3.3
Future revenues under contract	598.4	598.4
Contracts currently being invoiced	526.7	526.7
Backlog for sales bookings	$ 71.7	$ 71.7
Average remaining contract term of backlog sales bookings		5 years 1 month 6 days