| **Finance Receivables (Details 3) - USD ($) $ in Millions** | 3 Months Ended |
|-------------------------------------------------------------|----------------|
||
| **Financing Receivable, Allowance for Credit Losses**       |           |   |
| Beginning Balance                                           | $ 331          | $ 346 |
| Write-offs                                                  | (70)           | (20) |
| Recoveries                                                  | 15             | 10 |
| Financing Receivable, Credit Loss, Expense (Reversal)       | 9              | 11 |
| Financing Receivable, Allowance for Credit Losses, Other    | (4)            | 1 |
| Ending Balance                                              | 281            | 348 |
| Customer                                                    |           |   |
| **Financing Receivable, Allowance for Credit Losses**       |           |   |
| Beginning Balance                                           | 276            | 277 |
| Write-offs                                                  | (23)           | (20) |
| Recoveries                                                  | 15             | 10 |
| Financing Receivable, Credit Loss, Expense (Reversal)       | 9              | 10 |
| Financing Receivable, Allowance for Credit Losses, Other    | (4)            | 1 |
| Ending Balance                                              | 273            | 278 |
| Dealer                                                      |           |   |
| **Financing Receivable, Allowance for Credit Losses**       |           |   |
| Beginning Balance                                           | 51             | 65 |
| Write-offs                                                  | (47)           | 0 |
| Recoveries                                                  | 0              | 0 |
| Financing Receivable, Credit Loss, Expense (Reversal)       | 0              | 0 |
| Financing Receivable, Allowance for Credit Losses, Other    | 0              | 0 |
| Ending Balance                                              | 4              | 65 |
| Caterpillar Purchased Receivables                           |           |   |
| **Financing Receivable, Allowance for Credit Losses**       |           |   |
| Beginning Balance                                           | 4              | 4 |
| Write-offs                                                  | 0              | 0 |
| Recoveries                                                  | 0              | 0 |
| Financing Receivable, Credit Loss, Expense (Reversal)       | 0              | 1 |
| Financing Receivable, Allowance for Credit Losses, Other    | 0              | 0 |
| Ending Balance                                              | $ 4            | $ 5 |

| X                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Allowance for Credit Losses, Other
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase in allowance for credit loss on financing receivable from recovery.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of writeoff of financing receivable, charged against allowance for credit loss.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of credit loss expense (reversal of expense) for financing receivable.
+ References
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| X                                                                                                                                                                                  |
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