Pensions and Other Postretirement Benefits (Accrued Pension and Other Postretirement Costs) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Accrued pension and other postretirement costs	$ (14,982)	$ (16,424)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Accrued pension and other postretirement costs	(9,421)	(11,163)
OPEB Plans
Defined Benefit Plan Disclosure [Line Items]
Accrued pension and other postretirement costs	$ (4,645)	$ (4,726)

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant