Leases - Operating Lease Expense, Operating Lease Cash Flows and Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 1,610	$ 4,951
Operating cash outflows from operating leases	1,537	5,197
Operating lease right-of-use assets obtained in exchange for lease obligations	1,131	2,655
Cost of sales
Lessee, Lease, Description [Line Items]
Operating lease expense	574	1,627
Selling, general and administrative expenses
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 1,036	$ 3,324