SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Advertising Expense (Narrative) (Details) - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	May 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Advertising expenses	$ 59.6	$ 126.0	$ 201.2	$ 192.8
Advertising expense, barter costs	$ 46.0	$ 105.0	$ 155.2	$ 146.1