Quarterly Unaudited Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Net sales:	$ 265,201	$ 296,792	$ 255,184	$ 215,401	$ 226,034	$ 260,784	$ 224,255	$ 187,160	$ 1,032,578	$ 898,233	$ 837,097
Gross profit	62,426	78,495	65,561	49,861	57,426	68,744	56,468	37,259	256,343	219,897	210,926
Income from operations:	22,722	40,943	30,748	12,777	20,233	28,314	25,073	7,192	107,190	80,812	81,141
Interest expense, net	220	217	222	44	(5)	79	249	2,000	703	2,323	10,709
Income from continuing operations	17,598	31,334	24,457	9,902	15,043	21,951	18,803	4,131	83,291	59,928	54,112
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(26,143)	2,426	2,835	2,157	(686)	2,525	1,110	2,214	(18,725)	5,163	9,697
Net income	$ (8,545)	$ 33,760	$ 27,292	$ 12,059	$ 14,357	$ 24,476	$ 19,913	$ 6,345	$ 64,566	$ 65,091	$ 63,809
Income per share from continuing operations:
Basic (in dollars per share)	$ 0.54	$ 0.96	$ 0.75	$ 0.30	$ 0.46	$ 0.68	$ 0.58	$ 0.13	$ 2.55	$ 1.85	$ 1.69
Diluted (in dollars per share)	0.53	0.95	0.74	0.30	0.46	0.67	0.58	0.13	2.53	1.83	1.66
Income (loss) per share from discontinued operations:
Basic (in dollars per share)	(0.80)	0.07	0.09	0.07	(0.02)	0.07	0.04	0.07	(0.57)	0.16	0.31
Diluted (in dollars per share)	$ (0.79)	$ 0.07	$ 0.09	$ 0.07	$ (0.02)	$ 0.08	$ 0.03	$ 0.06	$ (0.57)	$ 0.16	$ 0.30