Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net sales	$ 453,042	$ 433,823	$ 409,788
Cost of sales	96,628	93,037	87,853
Gross profit	356,414	340,786	321,935
Sales and marketing	205,527	198,370	181,287
General and administrative	84,506	71,905	76,409
Research and development	33,218	29,700	28,803
Changes in fair value of contingent consideration	3,069
Charges related to U.S. Government resolutions (Note 13)			14,369
Operating income	30,094	40,811	21,067
Interest income (expense), net	(828)	(416)	763
Other expense, net	(6,381)	(4,004)	(2,806)
Income before income taxes	22,885	36,391	19,024
Income tax expense	(9,074)	(29,100)	(15,527)
Net income from continuing operations	13,811	7,291	3,497
Discontinued operations (Note 13)
Loss from discontinued operations		(1,759)	(638)
Income tax benefit		691	197
Net loss from discontinued operations		(1,068)	(441)
Net income	$ 13,811	$ 6,223	$ 3,056
Net income per common share—basic
Net income from continuing operations	$ 0.73	$ 0.40	$ 0.19
Net loss from discontinued operations		(0.06)	(0.02)
Net income per common share—basic	0.73	0.34	0.17
Net income per common share—diluted
Net income from continuing operations	0.72	0.39	0.19
Net loss from discontinued operations		(0.05)	(0.02)
Net income per common share—diluted	$ 0.72	$ 0.34	$ 0.17
Weighted average number of common shares:
Basic	18,494,002	18,117,405	18,144,019
Diluted	18,911,610	18,498,745	18,463,161
Other comprehensive income (loss), before tax
Unrealized gain (loss) on derivative instrument			$ (360)
Unrealized gain (loss) on debt security	$ 1,770	$ 3,830	(1,744)
Reclassification adjustment for loss on debt security in net income		5,585	2,727
Currency translation adjustment	(1,823)	4,552	(726)
Other comprehensive income (loss) before tax	(53)	13,967	(103)
Income tax expense related to items of other comprehensive income (loss)	(438)	(3,600)	(245)
Other comprehensive income (loss), net of tax	(491)	10,367	(348)
Comprehensive income	$ 13,320	$ 16,590	$ 2,708