Leases Leases - Supplemental Cash Flow and Balance Sheet Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Cash Flow, Lessee [Abstract]
Operating cash flows from operating leases	$ 961
Right-Of-Use Asset Obtained In Exchange For Lease Liability [Abstract]
Operating leases	$ 84
Weighted Average Remaining Lease Term [Abstract]
Operating leases (in years)	3 years 2 months 3 days
Leases, Weighted Average Discount Rate [Abstract]
Operating leases (as a percentage)	3.60%