Employee Benefit Plans (Effects of a One-Percentage Point Increase and Decrease in Assumed Health Care Cost Trend Rates) (Details) - Other Postretirement Benefits $ in Millions |
12 Months Ended |
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Dec. 31, 2017
USD ($)
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| Defined Benefit Plan Disclosure [Line Items] | |
| Increase in total service and interest costs | $ 7 |
| Increase in postretirement benefit obligation | 130 |
| Decrease in total service and interest costs | 5 |
| Decrease in postretirement benefit obligation | $ 98 |
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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 decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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