BASIS OF PRESENTATION - Out of Period Adjustments (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Out of Period Adjustments
Net sales	$ 652,752		$ 729,410		$ 1,914,603	$ 2,103,407
Gross profit	107,830		118,863		309,947	335,197
Net income	16,930		$ 23,750		$ 39,469	$ 60,145
Revenue Cutoff | Net Sales
Out of Period Adjustments
Mistatement in prior periods		$ (945)		$ (945)
Revenue Cutoff | Gross Profit
Out of Period Adjustments
Mistatement in prior periods		(4,214)		(4,214)
Revenue Cutoff | Net Income
Out of Period Adjustments
Mistatement in prior periods		$ (2,955)		$ (2,955)
Revenue Cutoff | Revision of Prior Period Error Correction Adjustment
Out of Period Adjustments
Net sales	945
Gross profit	4,214
Net income	$ 2,955