Condensed Consolidated Balance Sheets (unaudited) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 9,031,808	$ 4,763,364
Short term investments	38,839,967	44,254,862
Accounts receivable	4,928,293	3,810,792
Income tax receivable	282,537	494,711
Deferred royalty buy-down	1,491,948	1,451,893
Prepaid expenses and other current assets	583,636	624,345
Total current assets	55,158,189	55,399,967
Long-term investments	8,101,594	3,771,380
Deferred royalty buy-down - long term, net	1,573,428	1,976,456
Deferred tax assets, net	3,192,614	3,290,122
Patent costs, net	248,193	258,355
Total assets	68,274,018	64,696,280
Current liabilities:
Accounts payable and accrued expenses	1,161,443	738,649
Deferred revenue	1,362,890	1,179,848
Accrued liabilities of discontinued operations	78,138	78,138
Total current liabilities	2,602,471	1,996,635
Long-term deferred revenue	5,974,947	6,417,702
Stockholders' equity:
Series A Preferred stock, $.50 par value, 700,000 shares authorized; none outstanding	0	0
Common stock, $.001 par value; 10,000,000 shares authorized; 7,575,167 and 7,555,167 shares issued, 7,172,021 and 7,156,281 shares outstanding as of March 31, 2017 and December 31, 2016, respectively	7,575	7,555
Additional paid-in capital	33,236,946	32,945,240
Retained earnings	33,955,602	30,610,849
Treasury stock, 403,146 and 398,886 shares at cost as of March 31, 2017 and December 31, 2016, respectively	(7,503,523)	(7,281,701)
Total stockholders' equity	59,696,600	56,281,943
Total liabilities and stockholders' equity	$ 68,274,018	$ 64,696,280