Leases (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Leases
Lease practical expedients package [true false]			true
Lease practical expedient, use of hindsight [true false]			false
Operating lease cost	$ 161	$ 600	$ 316	$ 1,100
Classification of operating leases
Operating lease right-of-use assets	2,090		2,090
Operating lease liability, current	670		670
Operating Lease, Liability, Noncurrent	1,808		1,808
Lease cost
Operating Lease, Cost	161	$ 600	316	$ 1,100
Short-term Lease, Cost	61		110
Lease, Cost, Total	$ 222		$ 426
Lease Term and Discount Rate
Weighted average remaining lease term	4 years 6 months		4 years 6 months
Weighted average discount rate	6.90%		6.90%
Cash paid for amounts included in the measurement of lease liabilities
Cash flows from operating activities			$ 269
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities			$ 393
Minimum
Leases
Initial lease term	1 year		1 year
Maximum
Leases
Initial lease term	7 years		7 years