Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net loss	$ (7,211,821)	$ (10,932,590)	$ (14,984,321)
Adjustments to reconcile net loss to net cash from operating activities:
Depreciation and amortization	2,503,762	2,660,826	3,314,360
Share-based payment compensation	1,465,010	1,668,050	4,587,282
Non-cash professional services expenses	1,173	37,379	27,487
Gain on Estate litigation settlement	(5,293,319)	0	0
Restructuring costs	921,895	3,580,731	770,749
Payment of restructuring costs	(1,199,473)	(2,274,716)	(770,271)
Realized gain on marketable securities	0	(826)	(905)
Impairment of cost method investments	0	0	10,725
Gain on sale of cost method investment	0	(2,096,364)	0
Provision for returns and doubtful accounts	(64,904)	(294,074)	357,301
Deferred income tax provision	121,694	110,203	(83,350)
Changes in operating assets and liabilities:
Accounts receivable	2,394,162	3,327,614	4,849,209
Prepaid expenses and other current assets	(11,072)	1,129,742	(889,278)
Inventory	566,897	(276,571)	1,126,188
Other assets	168,042	(95,052)	31,837
Accounts payable	280,170	(1,809,000)	(101,784)
Accrued expenses and other long-term liabilities	(1,142,903)	(11,758,230)	(660,906)
Deferred revenue	6,991,933	5,887,953	(2,852,793)
Net cash provided by (used in) operating activities	491,246	(11,134,925)	(5,268,470)
Cash flows from investing activities:
Sales of marketable securities	39,131,215	33,982,164	32,332,954
Purchases of marketable securities	(41,958,829)	(31,527,129)	(21,267,582)
Proceeds from sale of cost method investment	0	3,000,000	0
Transfer from (to) restricted cash	750,000	0	(750,000)
Purchases of property and equipment	(758,906)	(1,536,167)	(2,487,128)
Capitalized software development costs	(184,215)	(973,842)	(461,555)
Security deposits	(16,723)	(244,814)	(29,746)
Purchase of intangible assets	(138,315)	(128,122)	(101,642)
Net cash (used in) provided by investing activities	(3,175,773)	2,572,090	7,235,301
Cash flows from financing activities:
Proceeds from exercise of stock options	24,684	697,500	738,184
Repurchase of common stock	(4,685,401)	0	0
Dividends paid on Series A redeemable convertible preferred stock	(777,091)	0	0
Proceeds from issuance of Series A redeemable convertible preferred stock, net of issuance costs	0	8,731,677	0
Net cash (used in) provided by financing activities	(5,437,808)	9,429,177	738,184
Effect of exchange rate changes on cash and cash equivalents	(292,114)	(229,470)	(311,241)
Net (decrease) increase in cash and cash equivalents	(8,414,449)	636,872	2,393,774
Cash and cash equivalents, beginning of period	19,288,340	18,651,468	16,257,694
Cash and cash equivalents, end of period	10,873,891	19,288,340	18,651,468
Supplemental Disclosures:
Cash paid for income taxes, net	186,194	95,593	688,167
Non-cash financing activities:
Undistributed Series A redeemable convertible preferred stock dividends	$ 186,904	$ 216,379	$ 0