Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Net sales	$ 59,695	$ 48,546	$ 155,934	$ 120,450
Cost of sales	29,039	23,766	71,389	57,189
Gross profit	30,656	24,780	84,545	63,261
Operating expenses:
Selling and marketing	20,052	15,690	48,451	37,463
General and administrative	4,293	4,959	9,871	10,762
Research and development	2,379	1,752	4,686	3,655
Total operating expenses	26,724	22,401	63,008	51,880
Operating income	3,932	2,379	21,537	11,381
Other income (expense):
Interest income	59	16	103	24
Interest expense	(6)	(5)	(11)	(12)
Other, net	(281)	(56)	(397)	(117)
Total other income (expense), net	(228)	(45)	(305)	(105)
Income from continuing operations before income taxes	3,704	2,334	21,232	11,276
Income tax provision	1,485	836	8,154	4,030
Income from continuing operations	2,219	1,498	13,078	7,246
Discontinued operations:
Loss from discontinued operations before income taxes	(160)	(322)	(313)	(834)
Income tax provision (benefit) from discontinued operations	(365)	619	(391)	481
Income (loss) from discontinued operations	205	(941)	78	(1,315)
Net income	$ 2,424	$ 557	$ 13,156	$ 5,931
Earnings Per Share, Basic [Abstract]
Basic income per share from continuing operations (in dollars per share)	$ 0.07	$ 0.05	$ 0.42	$ 0.23
Basic loss per share from discontinued operation (in dollars per share)	0.01	(0.03)	0.00	(0.04)
Basic net income per share (in dollars per share)	0.08	0.02	0.42	0.19
Earnings Per Share, Diluted [Abstract]
Diluted income per share from continuing operations (in dollars per share)	0.07	0.05	0.41	0.23
Diluted loss per share from discontinued operation (in dollars per share)	0.01	(0.03)	0.00	(0.04)
Diluted net income per share (in dollars per share)	$ 0.08	$ 0.02	$ 0.41	$ 0.19
Shares used in per share calculations:
Basic (in shares)	31,485	31,226	31,441	31,203
Diluted (in shares)	31,791	31,598	31,801	31,586