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Pension and Savings Plans (Details 3) - Pension Plan [Member] | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Weighted-average assumptions used to determine benefit obligations |  |  |  |
Discount rate |  | 4.15% | 4.55% |
Measurement date |  | Dec. 31, 2016 | Dec. 31, 2015 |
Weighted-average assumptions used to determine net periodic benefit cost |  |  |  |
Discount rate |  | 4.55% | 4.15% | 4.95%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets | 5.90% | 6.00% | 6.25% | 6.85%
Measurement date |  | December 31, 2015 | December 31, 2014 | December 31, 2013

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- Definition Measurement date at which the weighted-average assumptions are used to determine the benefit obligations as of the end of each year. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The measurement date for determining rate assumptions used in calculating the net periodic benefit cost (such as the weighted-average expected long-term rate of return on plan assets and the discount rate) is normally the beginning of the year measurement date. If an assumed rate(s) changes due to a subsequent interim measurement of both plan assets and obligations, disclosure of the beginning and more recently assumed rate(s), or a properly weighted combination of the two. Disclosure may include the more recent measurement date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2919-114920 + Details
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- Definition The interest rate used to adjust for the time value of money. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512046 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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