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Retirement Plans (Details 8)	Dec. 31, 2017	Dec. 31, 2016
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	100.00%	100.00%
U.S. Pension Plans | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	77.00%	74.00%
U.S. Pension Plans | Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	23.00%	25.00%
U.S. Pension Plans | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation		1.00%
U.S. Retiree Healthcare Plan
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	100.00%	100.00%
U.S. Retiree Healthcare Plan | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	65.00%	58.00%
U.S. Retiree Healthcare Plan | Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	35.00%	42.00%
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	100.00%	100.00%
Non-U.S. Pension Plans | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	7.00%	7.00%
Non-U.S. Pension Plans | Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	16.00%	18.00%
Non-U.S. Pension Plans | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	8.00%	6.00%
Non-U.S. Pension Plans | Insurance Contracts and Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit plan asset allocation	69.00%	69.00%

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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