Consolidated Balance Sheets - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 4,763,364	$ 5,137,875
Short term investments	44,254,862	28,347,542
Accounts receivable	3,810,792	2,547,920
Income tax receivable	494,711	916,843
Deferred royalty buy-down, net	1,451,893	1,017,981
Prepaid expenses and other current assets	624,345	383,810
Total current assets	55,399,967	38,351,971
Long-term investments	3,771,380	3,596,541
Deferred royalty buy-down - long term	1,976,456	2,851,423
Deferred tax assets, net	3,290,122	622,972
Patent costs, net	258,355	275,206
Total assets	64,696,280	45,698,113
Current liabilities:
Accounts payable and accrued expenses	738,649	611,009
Deferred revenue	1,179,848	149,378
Accrued liabilities of discontinued operations	78,138	78,138
Total current liabilities	1,996,635	838,525
Long-term deferred revenue	6,417,702	49,379
Commitments and contingencies (Note 10)
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; 7,555,167 and 7,290,167 shares issued, 7,156,281 and 6,918,579 outstanding at December 31, 2016 and 2015, respectively	7,555	7,290
Additional paid-in capital	32,945,240	31,797,418
Retained earnings	30,610,849	19,238,610
Treasury stock, 398,886 and 371,588 shares at cost as of December 31, 2016 and 2015	(7,281,701)	(6,233,109)
Total stockholders' equity	56,281,943	44,810,209
Total liabilities and stockholders' equity	$ 64,696,280	$ 45,698,113