LONG-TERM DEBT / INTEREST EXPENSE - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Interest income and other		$ (207)	$ (166)	$ 627
Interest expense, net		106,709	127,080	64,221
Senior Credit Facility
Debt Instrument [Line Items]
Amortization of discount and debt issuance costs		13,609	15,648	2,413
Interest expense, loss on debt financing, and amortization expense		97,199	116,868	48,575
Revolving Credit Facility | Senior Credit Facility
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		409	1,022	0
Revolving Credit Facility | Terminated revolving credit facility
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		0	316	4,685
Tranche B-1 Term Loan coupon
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		928	13,322	41,477
FILO Term Loan | Term Loan | FILO Term Loan coupon
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		27,380	22,143	0
Notes (net of $3.9 million and $11.5 million conversion feature and $0.5 million and $1.6 million discount) | Notes (net of $3.9 million and $11.5 million conversion feature and $0.5 million and $1.6 million discount)
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		2,576	2,828	4,272
Amortization of discount and debt issuance costs	$ 200	895	974	1,251
Amortization of conversion feature		6,246	6,576	9,496
Interest expense, loss on debt financing, and amortization expense		9,717	10,378	15,019
Tranche B-2 | Tranche B-1 Term Loan coupon | Amended Term Loan Facility Due March 2021
Debt Instrument [Line Items]
Interest expense, excluding amortization of conversion feature, discount and debt issuance costs		$ 54,873	$ 64,417	$ 0