Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Operating Leases
Operating lease right-of-use assets	$ 24,554	$ 23,901	$ 23,901
Current portion of operating lease liabilities included in "Other accrued liabilities"	7,906	7,722	7,722
Operating lease liabilities	17,081	$ 16,656	16,656
Total operating lease liabilities	$ 24,987		24,378
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherAccruedLiabilitiesCurrent	us-gaap:OtherAccruedLiabilitiesCurrent
Finance Leases
Property, plant and equipment, at cost	$ 11,107		15,367
Accumulated depreciation	(3,360)		(3,941)
Property, plant and equipment, net	$ 7,747		11,426
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
Current installments of finance lease obligations	$ 3,931	$ 6,758	6,758
Finance lease obligations	405	717	717
Total finance lease obligations	$ 4,336	$ 7,475	$ 7,475