VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Valuation and qualifying accounts [Roll forward]
Change in valuation allowance	$ 71,782
Federal and state
Valuation and qualifying accounts [Roll forward]
Change in valuation allowance		$ 128,931	$ 81,968
Federal
Valuation and qualifying accounts [Roll forward]
Change in valuation allowance		13,931	30,421
Allowance for Doubtful Accounts:
Valuation and qualifying accounts [Roll forward]
Balance at beginning of period	27,044	26,470	26,501
Charged to costs and expenses	25,370	30,632	25,132
Charged to other accounts	555	2,680	2,135
Deductions	(29,857)	(32,738)	(27,298)
Balance at end of period	23,112	27,044	26,470
Deferred Tax Valuation Allowance:
Valuation and qualifying accounts [Roll forward]
Balance at beginning of period	264,305	121,602	9,213
Charged to costs and expenses	71,782	142,862	111,797
Charged to other accounts	0	0	592
Deductions	0	(159)	0
Balance at end of period	336,087	$ 264,305	$ 121,602
Total decrease in valuation allowance due to Tax Act | Federal and state
Valuation and qualifying accounts [Roll forward]
Change in valuation allowance	294,568
Total decrease in valuation allowance due to Tax Act | Federal
Valuation and qualifying accounts [Roll forward]
Change in valuation allowance	$ (222,786)