Supplemental Balance Sheet Data and Cash Flow Information - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended		4 Months Ended	5 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2019	Jun. 02, 2019	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Interest paid	$ 5.5	$ 7.9	$ 7.9	$ 12.5	$ 17.0
Taxes paid	1.2	2.2	2.4	4.0	2.7
Capital leases	$ 0.0	$ 0.0	$ 0.0	$ 0.0	$ 0.3