Condensed Consolidated Statements of Cash Flows (unaudited) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 2,330,900	$ 753,989
Adjustments to reconcile net income to net cash provided By operating activities:
Amortization	172,554	44,845
Stock-based compensation expense	5,354	5,354
Deferred tax expense (benefit)	(841)	5,020
Gain on the sale of fixed assets	0	(1,150)
Changes in operating assets and liabilities:
Accounts receivable	(717,785)	3,072,312
Income tax receivable	13,996	(38,268)
Investment interest receivable	(18,260)	10,296
Prepaid expenses	(25,883)	(1,428)
Patent costs	0	(151,453)
Accounts payable and accrued expenses	239,885	242,809
Deferred revenue	(12,345)	(17,283)
Net cash provided by operating activities	1,987,575	3,925,043
Cash flows from investing activities:
Maturity of marketable investments	5,197,986	2,206,964
Purchases of marketable investments	(7,343,620)	(3,213,002)
Proceeds from sale of fixed asset	0	1,150
Net cash used in investing activities	(2,145,634)	(1,004,888)
Cash flows from financing activities:
Proceeds from stock option exercises	37,200	66,100
Payments for repurchase of common stock	(114,263)	(80,971)
Excess tax benefits from share-based payment arrangements	1,158,165	404,650
Net cash provided by financing activities	1,081,102	389,779
Increase in cash and cash equivalents	923,043	3,309,934
Cash and cash equivalents at beginning of year	9,810,816	5,624,860
Cash and cash equivalents at end of period	10,733,859	8,934,794
Cash paid during the year for:
Interest	0	0
Taxes	$ 80,000	$ 15,000