Consolidated Statements of Cash Flows (unaudited) (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income	$ 2,381,270	$ 1,409,072
Adjustments to reconcile net income to net cash provided By operating activities:
Depreciation and amortization	32,162	29,019
Stock-based compensation expense	105,449	175,685
Deferred tax assets	1,060	416,055
Changes in operating assets and liabilities:
Accounts receivable	1,178,418	416,072
Prepaid expenses and other current assets	(261,387)	72,403
Accounts payable and accrued expenses	147,694	(5,033)
Accrued taxes payable	382,704	102,471
Deferred revenue	(89,761)	(218,550)
Net cash provided by operating activities	3,877,609	2,397,194
Cash flows from investing activities:
Maturity of marketable investments	4,430,000	2,000,000
Purchases of marketable investments	(7,276,964)	(2,000,000)
Payment for royalty buy down	0	(1,500,000)
Net cash used in investing activities	(2,846,964)	(1,500,000)
Cash flows from financing activities:
Proceeds from stock option exercises	0	78,000
Payments for repurchase of common stock	(396,851)	(485,904)
Excess tax benefits from share-based payment arrangements	0	102,052
Net cash used in financing activities	(396,851)	(305,852)
Increase in cash and cash equivalents	633,794	591,342
Cash and cash equivalents at beginning of year	3,383,737	3,196,831
Cash and cash equivalents at end of period	4,017,531	3,788,173
Cash paid during the year for:
Interest	0	0
Taxes	$ 888,500	$ 92,000