| **Summary of Significant Accounting Policies - Product Warranty Liability (Details) - USD ($) $ / shares in Units, $ in Millions** | 3 Months Ended | 9 Months Ended |         |          |
|------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|---------|----------|
||
| **Product Liability Contingency [Line Items]**                                                                                     |           |           |    |     |   |   |   |   |
| Product Warranty Accrual                                                                                                           | $ 868          |           | $ 1,016 |     | $ 868 | $ 1,016 | $ 994 | $ 1,197 |
| Product Warranty Accrual, Warranties Issued                                                                                        |           |           |    |     | 141 | 208 |   |   |
| Product Warranty Accrual, Currency Translation, Increase (Decrease)                                                                |           |           |    |     | 2 | (7) |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:**                 |           |           |    |     |   |   |   |   |
| Adjustments to pre-existing warranties(A)(B)                                                                                       |           |           |    |     | 70 | (38) |   |   |
| **Extended Warranty Program:**                                                                                                     |           |           |    |     |   |   |   |   |
| Product Warranty Accrual, Payments                                                                                                 |           |           |    |     | (339) | (344) |   |   |
| Product Warranty Accrual, Current                                                                                                  | 423            |           | 466     |     | 423 | 466 |   |   |
| Product Warranty Accrual, Noncurrent                                                                                               | 445            |           | 550     |     | 445 | 550 |   |   |
| Extended Warranty Programs [Member]                                                                                                |           |           |    |     |   |   |   |   |
| **Extended Warranty Program:**                                                                                                     |           |           |    |     |   |   |   |   |
| Deferred Revenue, Revenue Recognized                                                                                               | 37             |           | 40      |     | 113 | 115 |   |   |
| Deferred Revenue                                                                                                                   | $ 345          |           |    |     | $ 345 |   | $ 401 |   |
| Product Warranty Accrual [Member]                                                                                                  |           |           |    |     |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:**                 |           |           |    |     |   |   |   |   |
| Adjustments to pre-existing warranties(A)(B)                                                                                       |           | $ 46           |    | $ (57)   |   |   |   |   |
| Product Warranty Accrual, Preexisting Increase Decrease Per Share, Net of Tax                                                      |           | $ 0.56         |    | $ (0.70) |   |   |   |   |
| Amortization of Loss Reserves [Member]                                                                                             |           |           |    |     |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:**                 |           |           |    |     |   |   |   |   |
| Prior Period Reclassification Adjustment                                                                                           |           |           |    |     |   | $ 31 |   |   |
| Discontinued Operations [Member] | Product Warranty Accrual [Member]                                                               |           |           |    |     |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:**                 |           |           |    |     |   |   |   |   |
| Adjustments to pre-existing warranties(A)(B)                                                                                       |           |           | $ 2     |     |   |   |   |   |

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| - Definition
Product Warranty Accrual, Preexisting Increase Decrease Per Share, Net of Tax
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| - Definition
Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.
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| - Definition
Amount of revenue recognized that was previously reported as deferred or unearned revenue.
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
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The amount of a reclassification adjustment made to prior period financial statement amounts.
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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.
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.
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| - Definition
Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.
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| - Definition
Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.
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Amount of increase in the standard and extended product warranty accrual from warranties issued.
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| - Definition
Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.
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