SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Barter and Trade Revenues and Expenses (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Barter and trade revenues	$ 165.8	$ 133.5	$ 78.3
Barter and trade expenses	$ 112.2	$ 112.1	$ 75.1