Basis of Presentation (Details 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Total Revenue	$ 3,788	$ 3,387	$ 6,767	$ 6,546
Product sales [Member]
Total Revenue	1,305	1,172	2,468	2,222
Royalties [Member]
Total Revenue	$ 2,483	$ 2,215	$ 4,299	$ 4,324