| **Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Millions** | 3 Months Ended | 9 Months Ended |
|-----------------------------------------------------------------------------------------|----------------|----------------|
||
| **Statement of Comprehensive Income [Abstract]**                                        |           |           |   |   |
| Net Income (Loss)                                                                       | $ (283)        | $ 419          | $ (413) | $ 811 |
| **Other Items of Comprehensive Income**                                                 |           |           |   |   |
| Net Change in Mutual Fund Investment                                                    | 0              | 0              | (11) | 0 |
| Less Tax Benefit                                                                        | 0              | 0              | 3 | 0 |
| Net Change in Pension and Other                                                         | 69             | 6              | 94 | 16 |
| Less Tax Expense                                                                        | (23)           | (2)            | (33) | (6) |
| Other Comprehensive Income                                                              | 46             | 4              | 53 | 10 |
| Comprehensive Income (Loss)                                                             | $ (237)        | $ 423          | $ (360) | $ 821 |

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| - Definition
Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.
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| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.
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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.
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Amount after tax of other comprehensive income (loss) attributable to parent entity.
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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.
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Amount of tax expense (benefit) allocated to other comprehensive income (loss).
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