Leases - Cash Payments Included in Measurement of Lease Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Finance leases
Operating cash flows included in operating activities	$ 132	$ 526
Financing cash flows included in payments under finance lease obligations	905	1,035
Operating leases
Operating cash flows (fixed payments) included in other operating activities, net	2,493	2,481
Operating cash flows (liability reduction) included in other operating activities, net	$ 1,949	$ 1,875