RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS - Impact of Restatement Adjustments on Condensed Consolidated Statements of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021		Jun. 30, 2020
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Sales	$ 285,691	$ 251,401	$ 531,278		$ 552,384
Cost of sales	200,413	181,320	374,370		399,189
Gross profit	85,278	70,081	156,908		153,195
Selling, general and administrative costs	70,432	62,943	135,829		134,738
Income before income taxes	9,614	3,075	11,034		10,851
Provision for income taxes	1,684	710	2,945		2,496
Net income	$ 7,930	$ 2,365	$ 8,089		$ 8,355
Basic (in dollars per share)	$ 0.42	$ 0.14	$ 0.44		$ 0.48
Diluted (in dollars per share)	$ 0.41	$ 0.13	$ 0.42	[1]	$ 0.45
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Sales		$ 251,401			$ 552,384
Cost of sales		181,705			398,703
Gross profit		69,696			153,681
Selling, general and administrative costs		62,943			136,013
Income before income taxes		2,690			10,062
Provision for income taxes		610			2,334
Net income		$ 2,080			$ 7,728
Basic (in dollars per share)		$ 0.12			$ 0.44
Diluted (in dollars per share)		$ 0.12			$ 0.42
Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Sales
Cost of sales		(385)			486
Gross profit		385			(486)
Selling, general and administrative costs		0			(1,275)
Income before income taxes		385			789
Provision for income taxes		100			162
Net income		$ 285			$ 627
Basic (in dollars per share)
Diluted (in dollars per share)

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