Leases - Maturities of operating and financing lease liabilities (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Operating Leases
2019	$ 2,060
2020	7,075
2021	5,712
2022	4,807
2023	1,257
Thereafter	1,091
Total lease payments	22,002
Impact of discounting	(4,754)
Total operating lease liabilities	17,248
Finance Leases
2019	6,241
2020	20,840
2021	12,567
2022	5,250
2023	810
Thereafter	55
Total lease payments	45,763
Impact of discounting	(120)
Total finance lease liabilities	$ 45,643