Leases - Maturities (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Maturities of leases
2019 (excluding the six months ended June 30, 2019)	$ 2,318
2020	4,392
2021	4,132
2022	3,815
2023	3,369
Thereafter	8,831
Total lease payments	26,857
Less: imputed interest	(4,354)
Total operating lease liabilities	$ 22,503