Leases - Maturities of lease liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Operating leases
2020 (excluding the first 3 months)	$ 5,270
2021	4,012
2022	3,139
2023	2,829
2024	2,700
Thereafter	2,354
Total lease payments	20,304
Less imputed interest	(2,305)
Total	17,999	$ 19,621
Financing leases
2020 (excluding the first 3 months)	269
2021	320
2022	93
2023	43
2024	12
Thereafter	0
Total lease payments	737
Less imputed interest	(44)
Total	$ 693	$ 751