Revenues (Narrative) (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Transaction price allocated to the remaining performance obligation	$ 1,509
Research and development milestone payments	4,854
Commercial sales milestone payments	$ 28,751
Percentages of recognized in next three year	60.00%
Percentages of remaining recognized in next two years	40.00%