Leases - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 5,454	$ 5,454
Operating lease liabilities	4,616	4,616
Current portion of operating lease liability	999	999
Operating lease payments	$ 394	$ 704
Operating lease, weighted average remaining lease term (in years)	4 years 11 months 27 days	4 years 11 months 27 days
Operating lease, weighted average discount rate, percent	5.30%	5.30%
Minimum
Lessee, Lease, Description [Line Items]
Lessee, operating lease, lease not yet commenced, operating lease expense	$ 3,000	$ 3,000
Operating lease, term of contract	1 year	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lessee, operating lease, lease not yet commenced, operating lease expense	$ 4,000	$ 4,000
Operating lease, term of contract	7 years	7 years
Operating Leases Commenced
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 1,000	$ 1,000
Operating lease liabilities	$ 0	$ 0
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets			$ 5,046
Operating lease liabilities			$ 5,131