Leases - Balance Sheet Location (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Operating leases
Operating lease right of use assets	$ 13,116
Operating lease liability, current	3,304
Operating lease liability, noncurrent	9,812	$ 0
Total operating lease liabilities	13,116
Finance leases
Property, plant, and equipment	3,462
Accumulated amortization	(2,668)
Property, plant, and equipment - net	794
Finance lease liability, current	609
Finance lease liability, noncurrent	184
Total finance lease liabilities	$ 793