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Employee Benefit Plans - Components of Expense/(Income) Related to Net Benefit Expense (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Components of expense/ (income) related to net benefit expense: |  |
Restructuring Charges - Non Operating (a) | $ 0 |
Pension Benefits |  |
Components of expense/ (income) related to net benefit expense: |  |
Service Cost Included in Labor and Fringe | 9 | $ 11
Interest Cost | 23 | 23
Expected Return on Plan Assets | (44) | (42)
Amortization of Net Loss | 10 | 11
Total Income Included in Other Income - Net | (11) | (8)
Net Periodic Benefit Cost | (2) | 3
Restructuring Charges - Non Operating (a) | 0 | 50
Total (Income) Expense | (2) | 53
Other Post-retirement Benefits |  |
Components of expense/ (income) related to net benefit expense: |  |
Interest Cost | 2 | 2
Amortization of Net Loss | 0 | 0
Net Periodic Benefit Cost | 2 | 2
Restructuring Charges - Non Operating (a) |  | 13
Total (Income) Expense | $ 2 | $ 15

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- Definition Defined Benefit Plan, Net Periodic Benefit Cost, Before Gain (Loss) Due to Settlements and Curtailments + References No definition available. + Details
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- Definition The impact related to special termination benefits/curtailments offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. This eliminates the accrual of defined benefits for future services related to affected employees. + References No definition available. + Details
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- Definition Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit 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 (h)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit 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 (h)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost recognized for passage of time related to defined benefit 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 (h)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of net periodic benefit cost (credit) for defined benefit 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 (h) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit 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 (h)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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