Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income (loss)	$ 2,981,075	$ 6,601,626	$ (1,508,540)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	64,190	50,685	18,949
Stock-based compensation expense	228,485	517,367	1,901,781
Deferred tax assets	1,474,904	(3,047,955)	0
Changes in operating assets and liabilities:
Accounts receivable	(1,845,443)	(1,250,792)	(459,291)
Prepaid expenses and other current assets	142,160	(65,642)	(28,664)
Accounts payable and accrued expenses	(242,233)	(3,009,109)	24,394
Deferred revenue	(372,705)	(483,769)	(831,111)
Net cash provided by (used in) operating activities from continuing operations	2,430,433	(687,589)	(882,482)
Cash flows from investing activities:
Maturities of marketable securities	5,070,000	5,360,970	4,548,541
Purchases of marketable securities	(5,190,000)	(5,000,000)	(5,360,970)
Payment for royalty buy down	(1,500,000)	0	0
Net cash provided by (used in) investing activities from continuing operations	(1,620,000)	360,970	(812,429)
Cash flows from financing activities:
Proceeds from stock option exercises	148,425	82,450	673,375
Repurchases of common stock	(1,034,647)	(739,551)	(458,001)
Excess tax benefits from share-based payment arrangements	262,695	1,709,699	0
Net cash provided by (used in) financing activities from continuing operations	(623,527)	1,052,598	215,374
Increase (decrease) in cash and cash equivalents	186,906	725,979	(1,479,537)
Cash and cash equivalents at beginning of year	3,196,831	2,470,852	3,950,389
Cash and cash equivalents at end of year	3,383,737	3,196,831	2,470,852
Cash paid during the year for:
Interest	0	0	0
Taxes	$ 232,000	$ 190,000	$ 9,851