Leases - Future annual minimum lease payments and finance lease commitments (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Operating Leases
2019 (remaining six months)	$ 7,785
2020	14,544
2021	12,236
2022	10,512
2023	9,892
2024 and thereafter	55,185
Total minimum lease payments	110,154
Finance Lease, Liability, Payment, Due [Abstract]
2019 (remaining six months)	877
2020	1,781
2021	1,816
2022	1,853
2023	465
2024 and thereafter	0
Total minimum lease payments	$ 6,792