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LONG-TERM DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Apr. 03, 2021	Dec. 31, 2020	Sep. 24, 2020	Nov. 16, 2018	Apr. 12, 2018
Debt Instrument [Line Items]
Unamortized discounts and unamortized deferred financing costs	$ (51,624)	$ (53,938)
Total long-term debt, net of unamortized discounts and unamortized deferred financing costs	3,584,939	3,589,029
Less: current portion of long-term debt	25,600	25,600
Total long-term debt, less current portion	$ 3,559,339	3,563,429
Debt instrument, interest rate, stated percentage	6.125%
Term loan facility due April 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,491,563	2,497,967
8.00% senior notes due April 2026
Debt Instrument [Line Items]
Long-term debt, gross	645,000	645,000
Total long-term debt, net of unamortized discounts and unamortized deferred financing costs	$ 645,000	$ 645,000
Debt instrument, interest rate, stated percentage	8.00%	8.00%		8.00%	8.00%
6.125% senior notes due January 2029
Debt Instrument [Line Items]
Long-term debt, gross	$ 500,000	$ 500,000
Total long-term debt, net of unamortized discounts and unamortized deferred financing costs	$ 500,000	$ 500,000
Debt instrument, interest rate, stated percentage	6.125%	6.125%	6.125%
Other Assets \| ABL Facility \| Asset-based lending credit facility, due 2023
Debt Instrument [Line Items]
Unamortized deferred financing costs	$ 1,500	$ 1,700