Right of Use Asset and Lease Liability (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Aug. 31, 2018
Right Of Use Asset and Lease Liability
Remaining term of operating lease (in years)			6 years 3 months
Operating lease discount rate	10.00%		10.00%
Lease term (in years)					6 years
Lease renewal term (in years)		5 years		5 years	5 years
Lessee, Operating Lease, Existence of Option to Extend [true false]			true
Rent expense, or operating lease costs	$ 177	$ 54	$ 353	$ 107
Cash payments in the measurement of operating lease liability			$ 100