| **Income Taxes - Reconciliation of Statutory Federal Income Tax Benefit (Expense) (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended |
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| **Income Tax Disclosure [Abstract]**                                                                                                         |            |   |   |
| Federal income tax benefit (expense) at the statutory rate of 35%                                                                            | $ (341)         | $ (389) | $ 155 |
| State income taxes, net of federal benefit                                                                                                   | 4               | 6 | 4 |
| Credits and incentives                                                                                                                       | 0               | 10 | 27 |
| Adjustments to valuation allowances                                                                                                          | 350             | 2,207 | (1,499) |
| Foreign operations                                                                                                                           | 8               | 17 | 19 |
| Adjustments to uncertain tax positions                                                                                                       | 16              | (11) | (42) |
| Effective Income Tax Rate Reconciliation, Tax Expense related to Equity Components                                                           | 220             | 0 | 0 |
| Non-controlling interest adjustment                                                                                                          | 19              | 17 | 19 |
| Other                                                                                                                                        | 31              | (23) | (8) |
| Recorded income tax benefit (expense)                                                                                                        | $ (171)         | $ 1,780 | $ (1,417) |

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| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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| - Definition
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).
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| - Definition
The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit).
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| - Definition
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in income tax contingencies. Including, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.
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| - Definition
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.
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