Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Oct. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization		$ 6,619	$ 3,659	$ 13,888
Upfront payment for developed technology		20,000	53,111	0
Accrued contract research organization charges		1,000	156
Transaction costs		3,111
Impairment of intangible asset		$ 66,087	0	$ 0
Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life (in years)		15 years
Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life (in years)		3 years
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Developed technology acquired			$ 73,111
Upfront payment for developed technology		$ 50,000
Accrued contract research organization charges		$ 20,000
Amortization period (in years)	13 years