Non-pension Post-retirement Benefits (Pre-tax Amounts Recognized in Accumulated Other Comprehensive Loss) (Details) - Non-pension Post-retirement Benefit Plans - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gain	$ (5,982)	$ (912)
Prior service cost (credit)	(980)	(1,262)
Total credit in AOCI	(6,962)	(2,174)
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gain	(5,176)	(80)
Prior service cost (credit)	(980)	(1,262)
Total credit in AOCI	(6,156)	(1,342)
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gain	(806)	(832)
Prior service cost (credit)	0	0
Total credit in AOCI	$ (806)	$ (832)