Restatement of Previously Issued Financial Statements (Quarterly Consolidated Statement of Operations) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue	$ 51,197	$ 42,713	$ 154,555	$ 114,755
Cost of revenue	30,084	24,571	93,636	66,932
Gross Profit	21,113	18,142	60,919	47,823
Operating expenses:
Selling, general and administrative	9,455	7,342	32,945	25,539
Research and development	5,450	5,084	16,851	15,948
Total operating expenses	14,905	12,426	49,796	41,487
Income (loss) from operations	6,208	5,716	11,123	6,336
Interest expense, net	(36)	(56)	(121)	(138)
Amortization of debt discount and prepaid debt costs	16	16	46	42
Income (loss) from operations before income taxes	6,156	5,644	10,956	6,156
Income tax provision	129	416	1,802	1,849
Net income (loss)	6,027	5,228	9,154	4,307
Net income (loss) per share:
Earnings per share, basic	$ 0.21	$ 0.18	$ 0.32	$ 0.15
Earnings per share, diluted	$ 0.21	$ 0.18	$ 0.32	$ 0.15
Weighted average common shares outstanding:
Weighted average number of shares outstanding, basic	28,884	28,736	28,857	28,511
Weighted average number of shares outstanding, diluted	28,940	28,748	28,883	28,695
Scenario, Previously Reported [Member]
Revenue		43,907		123,993
Cost of revenue		25,534		72,503
Gross Profit		18,373		51,490
Operating expenses:
Selling, general and administrative		7,344		24,868
Research and development		5,084		15,974
Total operating expenses		12,428		40,842
Income (loss) from operations		5,945		10,648
Interest expense, net		(56)		(138)
Amortization of debt discount and prepaid debt costs		16		42
Income (loss) from operations before income taxes		5,873		10,468
Income tax provision		470		1,903
Net income (loss)		5,403		8,565
Net income (loss) per share:
Earnings per share, basic		$ 0.19		$ 0.30
Earnings per share, diluted		$ 0.19		$ 0.30
Weighted average common shares outstanding:
Weighted average number of shares outstanding, basic		28,736		28,511
Weighted average number of shares outstanding, diluted		28,748		28,695
Restatement Adjustment [Member]
Revenue		(1,194)		(9,238)
Cost of revenue		(963)		(5,571)
Gross Profit		(231)		(3,667)
Operating expenses:
Selling, general and administrative		(2)		671
Research and development		0		(26)
Total operating expenses		(2)		645
Income (loss) from operations		(229)		(4,312)
Interest expense, net		0		0
Amortization of debt discount and prepaid debt costs		0		0
Income (loss) from operations before income taxes		(229)		(4,312)
Income tax provision		(54)		(54)
Net income (loss)		$ (175)		$ (4,258)
Net income (loss) per share:
Earnings per share, basic		$ (0.01)		$ (0.15)
Earnings per share, diluted		$ (0.01)		$ (0.15)