Commitments and Contingencies - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Operating Leases
Remaining 2019	$ 502
2020	611
2021	494
2022	466
2023	479
Thereafter	1,041
Total expected minimum lease obligation	3,593
Less: Amount representing interest	(615)
Operating lease liabilities	2,978
Finance Leases
Remaining 2019	415
2020	532
2021	519
2022	40
2023	317
Thereafter	0
Total expected minimum lease obligation	1,823
Less: Amount representing interest	(151)
Present value of net minimum lease payments	$ 1,672
Operating Leases
2019		$ 717
2020		611
2021		494
2022		466
2023		479
Thereafter		1,041
Total expected minimum lease obligation		3,808
Capital Leases
2019		532
2020		532
2021		519
2022		317
2023		40
Thereafter		0
Total expected minimum lease obligation		1,940
Less: Amount representing interest		(151)
Present value of net minimum lease payments		$ 1,789

Amount of minimum lease payments for capital leases.

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