Commitments and Contingencies - Maturities of Lease Liabilities and Minimum Lease Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Operating Leases
2019	$ 887
2020	1,809
2021	1,587
2022	1,460
2023	1,369
2024	1,175
Thereafter	9,938
Total lease payments	18,225
Less imputed interest	(4,019)
Total	14,206
Finance Leases
2019	490
2020	986
2021	987
2022	987
2023	1,506
2024	940
Thereafter	1,645
Total lease payments	7,541
Less imputed interest	(1,331)
Total	$ 6,210
Previous Lease Accounting Standard, Minimum Lease Payments
2019		$ 1,771
2020		1,709
2021		1,485
2022		1,355
2023		1,261
Thereafter		10,538
Total		$ 18,119

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