Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Earnings Per Share, Basic	$ 3.35	$ (0.19)	$ 0.03
Net sales	$ 305,907	$ 276,573	$ 275,834
Cost of goods sold	122,889	108,511	106,710
Gross profit	183,018	168,062	169,124
Operating expenses:
Selling Expense	98,025	92,908	90,093
General and Administrative Expense	80,479	76,611	75,979
Selling, general and administrative expenses	178,504	169,519	166,072
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	(5,422)	0	0
Environmental remediation expense	0	0	931
Operating expenses	173,082	169,519	167,003
Operating income (loss)	9,936	(1,457)	2,121
Interest expense	(622)	(496)	(766)
Other income (expenses), net	780	422	(203)
Income (loss) before income taxes	(10,094)	1,531	(1,152)
Income tax (benefit) expense	(19,594)	98	855
Net Income (loss)	$ 29,688	$ (1,629)	$ 297
Earnings Per Share, Diluted	$ 3.25	$ (0.19)	$ 0.03
Weighted Average Number of Shares Outstanding, Basic	8,864	8,780	8,726
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	267	0	150
Weighted Average Number of Shares Outstanding, Diluted	9,131	8,780	8,876
Comprehensive income (loss)
Net income (loss)	$ 29,688	$ (1,629)	$ 297
Other comprehensive loss, net of tax:
Adjustment for foreign currency translation	861	427	(1,892)
Comprehensive income (loss)	$ 30,549	$ (1,202)	$ (1,595)