Leases - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Jul. 31, 2019	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Lessee, Lease, Description [Line Items]
Operating lease expense		$ 200	$ 400
Finance lease expense		100	200
Short term lease costs		2,000	4,100
Cash paid for operating leases		200	400
Cash paid for finance leases		100	237	$ 0
Right-of-use assets obtained in exchange for lease obligations		$ 0	$ 600
Operating lease, weighted average lease term		2 years 1 month 20 days	2 years 1 month 20 days
Finance lease, weighted average lease term		1 year 8 months 1 day	1 year 8 months 1 day
Operating lease, weighted average discount rate (as a percent)		4.35%	4.35%
Finance lease, weighted average discount rate (as a percent)		6.91%	6.91%
Minimum
Lessee, Lease, Description [Line Items]
Renewal term			1 year
Maximum
Lessee, Lease, Description [Line Items]
Renewal term			3 years
Subsequent Event
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets period increase (decrease)	$ 2,400
Operating lease liability period increase (decrease)	$ 2,400