Commitments and Contingencies - Maturities of Lease Liabilities and Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Operating Leases
2019	$ 451
2020	1,892
2021	1,673
2022	1,516
2023	1,396
2024	1,253
Thereafter	10,067
Total lease payments	18,248
Less imputed interest	(3,942)
Total	14,306
Finance Leases
2019	245
2020	986
2021	987
2022	987
2023	1,506
2024	940
Thereafter	1,645
Total lease payments	7,296
Less imputed interest	(1,248)
Total	$ 6,048
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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