Unaudited Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement [Abstract]
Revenue	$ 93,586	$ 78,303	$ 171,829	$ 157,498
Cost of revenue	(55,992)	(45,278)	(101,605)	(91,022)
Gross margin	37,594	33,025	70,224	66,476
Expenses:
Selling, general and administrative	(21,081)	(15,776)	(39,098)	(30,689)
Depreciation and amortization	(2,003)	(1,038)	(3,193)	(1,996)
Research and development	(979)	(622)	(1,854)	(1,454)
Total expenses	(24,063)	(17,436)	(44,145)	(34,139)
Income from operations	13,531	15,589	26,079	32,337
Other income (expense):
Loss on extinguishment of debt	0	(995)	0	(6,386)
Change in fair value of warrant liability	0	6,524	0	2,649
Interest expense	(531)	(2,164)	(965)	(4,415)
Other income (expense), net	170	(343)	58	(350)
Total other income (expense)	(361)	3,022	(907)	(8,502)
Income before income taxes	13,170	18,611	25,172	23,835
Income tax expense	(4,730)	(5,433)	(8,967)	(7,051)
Net income	$ 8,440	$ 13,178	$ 16,205	$ 16,784
Earnings per common share:
Basic earnings per common share	$ 0.17	$ 0.27	$ 0.33	$ 0.35
Diluted earnings per common share	$ 0.16	$ 0.25	$ 0.31	$ 0.33
Weighted average common shares:
Weighted average common shares used in computing basic earnings per common share	51,086	48,227	49,841	47,890
Weighted average common shares used in computing diluted earnings per common share	53,713	54,032	52,445	50,586