Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2012
Site Contingency [Line Items]
Proceeds from Legal Settlements		$ 110,000
Recovery of Direct Costs	$ 37,000
Sales covered by the Iran Threat Reduction and Syria Human Rights Act of 2012	4,770
Huntsville Site [Member]
Site Contingency [Line Items]
Environmental Remediation Expense To Date	6,800
Additional Expected Project Expenditures Low Estimate	3,600
Additional Expected Project Expenditures High Estimate	10,000
Groundwater Removal [Member] | Norco Site [Member]
Site Contingency [Line Items]
Environmental Remediation Expense To Date	73,800
Additional Expected Project Expenditures Low Estimate	7,700
Additional Expected Project Expenditures High Estimate	$ 18,400