Leases - Future minimum payments for finance and operating leases (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Finance leases
2021	$ 251
2022	251
2023	84
Total future minimum lease payments	586
Amounts representing interest	(49)
Total finance lease liabilities	537	$ 640
Operating leases
2021	2,293
2022	2,085
2023	1,981
2024	1,255
2025	738
Thereafter	1,913
Total future minimum lease payments	10,265
Amounts representing interest	(1,011)
Total operating lease liabilities	$ 9,254	$ 8,864