Leases - Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Lease, Cost [Abstract]
Operating cash flows for operating leases	$ 2,214	$ 4,305
Finance cash flows for finance leases	290	580
Operating right-of-use assets obtained in exchange for lease obligations during the current period	$ 1,718	$ 2,211