ALLOWANCE FOR DOUBTFUL ACCOUNTS AND CUSTOMER DISPUTES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts and Customer Disputes
Balance, beginning of period	$ 6.1	$ 5.8
Provision for doubtful accounts and customer disputes	3.2	4.6
Uncollectible receivables written off, net of recoveries	(4.7)	(4.3)
Other adjustments	(0.6)	0.0
Balance, end of period	$ 4.0	$ 6.1