Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Net sales	$ 274,447	$ 218,803	$ 193,926
Cost of sales	133,872	112,326	102,889
Gross profit	140,575	106,477	91,037
Operating expenses:
Selling and marketing	81,059	66,486	58,617
General and administrative	22,131	18,705	17,669
Research and development	7,231	5,562	4,163
Total operating expenses	110,421	90,753	80,449
Operating income	30,154	15,724	10,588
Other income (expense):
Interest income	63	14	18
Interest expense	(25)	(36)	56
Other	32	337	(246)
Total other income (expense)	70	315	(172)
Income from continuing operations before income taxes	30,224	16,039	10,416
Income tax provision (benefit)	9,841	(32,085)	(226)
Income from continuing operations	20,383	48,124	10,642
Discontinued operations:
Income (loss) from discontinued operations before income taxes	(1,134)	(559)	6,007
Income tax provision (benefit) of discontinued operations	454	(389)	(234)
Income (loss) from discontinued operations	(1,588)	(170)	6,241
Net income	$ 18,795	$ 47,954	$ 16,883
Basic net income per share
Basic income per share from continuing operations (in dollars per share)	$ 0.65	$ 1.55	$ 0.34
Basic income (loss) per share from discontinued operations (in dollars per share)	$ (0.05)	$ (0.01)	$ 0.21
Basic net income per share (in dollars per share)	$ 0.60	$ 1.54	$ 0.55
Diluted net income per share
Diluted income per share from continuing operations (in dollars per share)	$ 0.64	$ 1.53	$ 0.34
Diluted income (loss) per share from discontinued operations (in dollars per share)	$ (0.05)	$ (0.01)	$ 0.21
Diluted net income per share (in dollars per share)	$ 0.59	$ 1.52	$ 0.55
Shares used in per share calculations:
Basic (in shares)	31,253	31,072	30,851
Diluted (in shares)	31,688	31,457	30,974