Subsequent Events (Details) (USD $)	3 Months Ended		6 Months Ended			0 Months Ended	1 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Aug. 21, 2013 Subsequent event	Aug. 31, 2013 Subsequent event item	Aug. 21, 2013 Subsequent event Forecast
Subsequent event
Quarterly cash dividend declared (in dollars per share)	$ 0.11	$ 0.105	$ 0.22	$ 0.21		$ 0.11
Estimated dividend payment	$ 610,251		$ 610,251		$ 579,386			$ 610,000
Obligated payment under the license and development agreement							$ 200,000
Number of licenses acquired							2
Term of licenses acquired							4 years