| **Tax Matters - Narrative (Details) $ in Millions**                                                  | 12 Months Ended |
|------------------------------------------------------------------------------------------------------|-----------------|
||
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Undistributed earnings of foreign subsidiaries                                                       | $ 86,000        |   |   |
| Unrecognized tax benefits excluding associated interest                                              | $ 4,600         | $ 4,800 |   |
| Number of tax jurisdiction associated with uncertain tax positions | jurisdiction                    | 1               |   |   |
| Deferred tax assets associated with unrecognized tax benefits                                        | $ 1,200         | 1,100 |   |
| Unrecognized tax benefits, interest on income taxes expense                                          | 72              | 71 | $ 40 |
| Unrecognized tax benefits, interest on income taxes accrued                                          | 771             | 714 |   |
| Unrecognized accrued interest decrease as a result of cash payments                                  | 18              | 5 |   |
| Significant change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit | (100)           |   |   |
| Noncurrent Deferred Tax Assets And Other Noncurrent Tax Assets [Member]                              |            |   |   |
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Deferred tax assets associated with unrecognized tax benefits                                        | 1,000           | 963 |   |
| Deferred Tax Liabilities, Net, Noncurrent [Member]                                                   |            |   |   |
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Deferred tax assets associated with unrecognized tax benefits                                        | 201             | 179 |   |
| Income Taxes Payable [Member]                                                                        |            |   |   |
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Unrecognized tax benefits, interest on income taxes accrued                                          | 4               |   |   |
| Current Tax Assets [Member]                                                                          |            |   |   |
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Unrecognized tax benefits, interest on income taxes accrued                                          | 13              | 12 |   |
| Other Taxes Payable [Member]                                                                         |            |   |   |
| **Income Tax Contingency [Line Items]**                                                              |            |   |   |
| Unrecognized tax benefits, interest on income taxes accrued                                          | $ 754           | $ 702 |   |

| X                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Deferred Tax Assets Associated With Unrecognized Tax Benefits
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Number of Tax Jurisdiction Associated with Uncertain Tax Positions
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| X                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Unrecognized Tax Benefits, Excluding Interest
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| X                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Unrecognized Tax Benefits, Interest on Income Taxes Accrued, Increase (Decrease) In Accrual
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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.
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| - Definition
The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of interest expense accrued for an underpayment of income taxes.
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| - Definition
Amount of interest expense for an underpayment of income taxes.
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