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LONG-TERM DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Oct. 03, 2020	Sep. 24, 2020	Dec. 31, 2019	Nov. 16, 2018	Apr. 12, 2018
Debt Instrument [Line Items]
Unamortized discounts and unamortized deferred financing costs	$ (56,470)		$ (56,063)
Total long-term debt, net of unamortized discounts and unamortized deferred financing costs	3,592,902		3,182,524
Less: current portion of long-term debt	25,600		25,600
Total long-term debt, less current portion	$ 3,567,302		3,156,924
Debt instrument, interest rate, stated percentage	6.125%
Asset-based revolving credit facility due April 2023
Debt Instrument [Line Items]
Long-term debt, gross	$ 0		70,000
Term loan facility due April 2025
Debt Instrument [Line Items]
Long-term debt, gross	2,504,372		2,523,587
Cash flow revolver due April 2023
Debt Instrument [Line Items]
Long-term debt, gross	0		0
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		$ 0
Total long-term debt, net of unamortized discounts and unamortized deferred financing costs	$ 500,000		$ 0
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	$ 1,900		$ 2,400