INCOME TAXES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current [Abstract]
Federal	$ 28,765	$ 29,638	$ 25,937
Foreign	2,670	3,021	2,141
State	2,483	2,982	2,412
Deferred [Abstract]
Federal	(7,114)	(6,815)	(5,772)
Foreign	52	58	85
State	106	(1,543)	(577)
Total income tax provision	$ 26,962	27,341	24,226
Federal statutory rate	35.00%
Income tax reconciliation [Abstract]
Income tax at Federal statutory rate	$ 29,027	30,471	26,968
State income taxes, net of Federal income taxes	1,510	556	1,182
Domestic production activities deduction	(3,299)	(2,709)	(2,567)
Other	(276)	(977)	(1,357)
Total income tax provision	26,962	27,341	24,226
Deferred tax assets [Abstract]
Inventories	2,378	1,432
Restricted stock and stock options	5,100	4,956
Other	2,629	807
Total deferred tax assets	10,107	7,195
Deferred tax liabilities [Abstract]
Amortization	56,111	49,726
Depreciation	27,435	22,464
Prepaid expense	0	658
Other	48	752
Total deferred tax liabilities	83,594	73,600
Net deferred tax liability	73,487	66,405
Valuation allowance for deferred tax assets	0	0
Reconciliation of unrecognized tax benefits [Roll Forward]
Balance at beginning of period	6,570	5,205	3,076
Increases for tax positions of prior years	332	943	1,922
Decreases for tax positions of prior years	(406)	(120)	(417)
Increases for tax positions related to current year	141	542	624
Balance at end of period	6,637	6,570	5,205
Interest and penalties	94	138	$ 37
Accrued interest and penalties	$ 2,486	$ 2,405