Employee Benefit Plans (Expected Benefit Payments for Company's Pension and Postretirement Plans as well as Expected Medicare Part D Subsidy Receipts Related to Postretirement Plan) (Details) $ in Millions |
Dec. 31, 2017
USD ($)
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|---|---|
| Pension Benefits | |
| Defined Benefit Plan Disclosure [Line Items] | |
| 2018 | $ 789 |
| 2019 | 849 |
| 2020 | 803 |
| 2021 | 827 |
| 2022 | 866 |
| 2023-2027 | 4,534 |
| Total | 8,668 |
| Other Postretirement Benefits | |
| Defined Benefit Plan Disclosure [Line Items] | |
| 2018 | 149 |
| 2019 | 152 |
| 2020 | 154 |
| 2021 | 155 |
| 2022 | 155 |
| 2023-2027 | 766 |
| Total | 1,531 |
| Other Postretirement Benefits– Medicare Part D Subsidy Receipts | |
| Defined Benefit Plan Disclosure [Line Items] | |
| 2018 | 10 |
| 2019 | 10 |
| 2020 | 10 |
| 2021 | 11 |
| 2022 | 11 |
| 2023-2027 | 59 |
| Total | $ 111 |
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- Definition The aggregate amount of benefits expected to be paid in the first, second, third, fourth and fifth fiscal years and the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan No definition available.
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- Definition The aggregate amount of the prescription drug subsidy receipts to be received in the first, second, third, fourth, fifth fiscal years and after the fifth fiscal year following the latest fiscal year. No definition available.
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- Definition 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. No definition available.
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- Definition Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prescription drug subsidy receipts expected in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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