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Retirement Plans (Details 8) | Dec. 31, 2017 | Dec. 31, 2016
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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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- 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 + Details
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