Leases - Lease Costs (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 1,381
Short-term lease cost	1,935
Short-term lease cost - related party	902
Total lease	4,218
Cash paid for amounts included in the measurement of lease liabilities - operating leases	$ 1,362
Weighted-average remaining lease term - operating leases	6 years 4 days
Weighted-average discount rate - operating leases	5.50%