REVENUE - Allowance for Doubtful Accounts (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	$ 5.3	$ 4.8	$ 4.0
Provision for doubtful accounts	0.2	0.4	0.6
Write-offs, net of recoveries and other	(0.3)	0.1	0.2
Balance at June 30, 2020	$ 5.2	$ 5.3	$ 4.8