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Retirement Plans (Details 9) | 12 Months Ended
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Dec. 31, 2017
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan investment goals | The asset allocation policy for the U.S. Pension Plans and U.S. Retiree Healthcare Plan was developed in consideration of the following long-term investment objectives: achieving a return on assets consistent with the investment policy, achieving portfolio returns which exceed the average return for similarly invested funds and maximizing portfolio returns with at least a return of 2.5% above the one-year constant maturity Treasury bond yield over reasonable measurement periods and based on reasonable market cycles.
Defined benefit plan diversification | The Company targets a 30% allocation of its U.S. retirement plans’ equity portfolio to be invested in financial markets outside of the United States.
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Equity Securities |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 70.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Equity Securities | Minimum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 50.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Equity Securities | Maximum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 90.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Debt Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 25.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Debt Securities [Member] | Minimum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 20.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Debt Securities [Member] | Maximum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 60.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Cash and Cash Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 5.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Cash and Cash Equivalents [Member] | Minimum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 0.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Cash and Cash Equivalents [Member] | Maximum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 20.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Insurance Contracts and Other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 0.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Insurance Contracts and Other [Member] | Minimum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 0.00%
U. S. Pension Plans And U. S. Retiree Healthcare Plan [Member] | Insurance Contracts and Other [Member] | Maximum |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 20.00%
Non-U.S. Pension Plans | Equity Securities |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 5.00%
Non-U.S. Pension Plans | Debt Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 20.00%
Non-U.S. Pension Plans | Cash and Cash Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 10.00%
Non-U.S. Pension Plans | Insurance Contracts and Other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target plan asset allocation in defined benefit plan | 65.00%

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- Definition Description of diversification use that is pertinent to an understanding of the plan investment policies and strategies. + 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)(i) -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)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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