INCOME TAXES - Income tax reconciliation (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Jan. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes
Statutory tax rate										35.00%
Reconciliation of effective income tax amount
Tax at statutory rate										$ (92,586)	$ (20,962)	$ (25,101)
State income taxes										(4,219)	1,483	905
Foreign income taxes										(565)	(1,356)	2,654
Nondeductible transaction costs										27,311
Nondeductible goodwill impairment										10,497
Permanent differences										438	4,405	(172)
Changes in valuation allowance										(6,159)	6,075	(6,880)
Unremitted earnings											1,686
Changes in U.S. tax rates										(4,784)
Deemed mandatory repatriation										7,441
Other										2,380	(3,118)	1,782
Income tax benefit		$ (27,322)	$ (37,002)	$ 2,074	$ 2,004	$ (1,818)	$ (3,757)	$ (3,130)	$ (3,082)	(60,246)	$ (11,787)	$ (26,812)
Provisional income tax benefit										9,400
Provisional income tax expense										$ 9,100
Forecast
Income Taxes
Statutory tax rate	21.00%