Pensions and Other Employee Benefits Plans (Amounts Recognized in the Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Long-Term Liabilities	$ 14,757	$ 18,336
Amounts recognized in the balance sheet	14,757	18,336
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current Liabilities	69	69
Long-Term Liabilities	410	450
Amounts recognized in the balance sheet	$ 479	$ 519