Environmental and Legal Contingencies (Details 5) - Asbestos Issue [Member] $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) claims-lawsuits	Dec. 31, 2016 USD ($) claims-lawsuits	Dec. 31, 2015 USD ($) claims-lawsuits
Loss Contingency, Claims Quantities [Abstract]
New Claims Filed	58	40	52
Pending Claims Disposed Of	61	84	68
Liability for Asbestos and Environmental Claims, Net, Claims Paid \| $	$ 1.2	$ 0.9	$ 1.9

Amount of cash outflow to settle insured claims and pay costs incurred in the claims settlement process attributable to asbestos and environmental claims.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437

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The number of claims settled and dismissed during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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The total number of new claims filed pertaining to a loss contingency during the period.

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