Statements Of Income (USD $)	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Revenue
Product sales	$ 5,974,606	$ 7,030,745
Contract research and development	202,327	432,160
Total revenue	6,176,933	7,462,905
Cost of sales	1,378,355	1,802,353
Gross profit	4,798,578	5,660,552
Expenses
Selling, general , and administrative	552,804	536,110
Research and development	962,911	688,026
Total expenses	1,515,715	1,224,136
Income from operations	3,282,863	4,436,416
Interest income	526,339	562,618
Income before taxes	3,809,202	4,999,034
Provision for income taxes	1,242,377	1,621,376
Net income	$ 2,566,825	$ 3,377,658
Net income per share - basic	$ 0.53	$ 0.70
Net income per share - diluted	$ 0.53	$ 0.69
Weighted average shares outstanding
Basic	4,862,436	4,824,745
Diluted	4,884,902	4,886,873