Consolidated Statements of Comprehensive Income (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenue	$ 125,991	$ 98,939	$ 64,919
Cost of revenue	49,853	39,324	25,443
Gross profit	76,138	59,615	39,476
Operating expenses
Marketing and sales	18,098	15,752	10,867
Research and development	9,137	5,222	4,281
General and administrative	13,957	11,772	7,629
Loss on impairment of foreign subsidiary assets			773
Total operating expenses	41,192	32,746	23,550
Income from operations	34,946	26,869	15,926
Other income (expense), net	23	(114)	(213)
Income before income taxes	34,969	26,755	15,713
Provision for income taxes	10,944	8,783	4,762
Net income	24,025	17,972	10,951
Less: dividends on redeemable preferred stock		(4,179)	(4,179)
Less: undistributed earnings allocated to preferred shareholders		(4,507)	(2,377)
Net income attributable to common shareholders	24,025	9,286	4,395
Net income per share:
Basic	$ 1.03	$ 0.75	$ 0.40
Diluted	$ 0.98	$ 0.67	$ 0.34
Shares used to compute net income per share:
Basic	23,373,593	12,352,004	11,079,432
Diluted	24,443,665	13,939,072	13,051,458
Other Comprehensive Income, net of tax
Foreign currency translation adjustments	(190)	(280)	(214)
Comprehensive income	$ 23,835	$ 17,692	$ 10,737