Consolidated Statements of Cash Flows (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net loss	$ (4,904,012)	$ (3,293,505)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	205,752	236,648
Compensation associated with issuance of stock options	109,248	414,283
Accretion of royalty liability	29,050	24,325
Changes in assets and liabilities:
Decrease in accounts receivable	589,883	316,900
(Increase) decrease in prepaid expenses and other current assets	(99,681)	6,205
Decrease (increase) in other assets	3,341	(1,135)
Increase (decrease) in accounts payable and accrued expenses	240,538	(594,149)
Increase (decrease) in deferred revenue	1,966,821	(73,339)
Decrease in royalty liability	(55,870)	(99,911)
Decrease in other long-term liabilities	(9,713)	(11,780)
Net cash used in operating activities	(1,924,643)	(3,075,458)
Cash flows from investing activities:
Acquisition of property and equipment	(34,432)	(24,757)
Net cash used in investing activities	(34,432)	(24,757)
Cash flows from financing activities:
Net proceeds from issuance of common stock	3,338,470	5,323,717
Net cash provided by financing activities	3,338,470	5,323,717
Net increase in cash and cash equivalents	1,379,395	2,223,502
Cash and cash equivalents at beginning of period	1,777,414	2,120,102
Cash and cash equivalents at end of period	3,156,809	4,343,604
Cash paid during the period for:
Interest	$ 28,168	$ 37,620