Consolidated Condensed Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net sales	$ 193,433	$ 181,027	$ 374,634	$ 358,967
Cost of sales	91,011	87,529	174,472	173,187
Gross profit	102,422	93,498	200,162	185,780
Selling and administrative expense	86,729	73,581	172,672	148,367
Research and development expense	8,009	7,501	16,267	14,043
Total operating expenses	94,738	81,082	188,939	162,410
Income from operations	7,684	12,416	11,223	23,370
Other expense	0	0	2,942	0
Interest expense	3,757	1,489	7,587	2,949
Income before income taxes	3,927	10,927	694	20,421
Provision for income taxes	1,043	3,466	75	6,648
Net income	2,884	7,461	619	13,773
Comprehensive income	$ 1,345	$ 8,630	$ 2,132	$ 4,915
Per share data:
Basic (in dollars per share)	$ 0.10	$ 0.27	$ 0.02	$ 0.50
Diluted (in dollars per share)	0.10	0.27	0.02	0.49
Dividends per share of common stock (in dollars per share)	$ 0.20	$ 0.20	$ 0.40	$ 0.40
Weighted average common shares:
Basic (shares)	27,776	27,620	27,753	27,603
Diluted (shares)	27,941	27,857	27,926	27,839