| **Financing Activities (Details 3) - USD ($) $ in Millions**        | 9 Months Ended | 12 Months Ended |         |         |
|---------------------------------------------------------------------|----------------|-----------------|---------|---------|
||
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Allowance for credit losses                                         | $ 401          | $ 387           | $ 348   | $ 401   |
| Allowance for credit losses as a percent of net finance receivables |           |            | 1.26%   | 1.36%   |
| Increase (decrease) in Allowance for credit losses                  | (53)           |            |    |    |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Balance at beginning of year                                        | 401            | 387             |    |    |
| Receivables written off                                             | (151)          | (146)           |    |    |
| Recoveries on receivables previously written off                    | 32             | 47              |    |    |
| Provision for credit losses                                         | 88             | 136             |    |    |
| Adjustment due to sale of receivables                               | (1)            | (3)             |    |    |
| Foreign currency translation adjustment                             | (21)           | (20)            |    |    |
| Balance at end of period                                            | 348            | 401             |    |    |
| **Allowance for Credit Losses**                                     |           |            |    |    |
| Individually evaluated for impairment                               |           |            | $ 82    | $ 75    |
| Collectively evaluated for impairment                               |           |            | 266     | 326     |
| Allowance, Ending Balance                                           | 401            | 387             | 348     | 401     |
| **Recorded Investment in Finance Receivables**                      |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 565     | 614     |
| Collectively evaluated for impairment                               |           |            | 27,026  | 28,861  |
| Recorded Investment in Finance Receivables, Ending Balance          |           |            | 27,591  | 29,475  |
| Customer                                                            |           |            |    |    |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Allowance for credit losses                                         | 388            | 374             | 336     | 388     |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Balance at beginning of year                                        | 388            | 374             |    |    |
| Receivables written off                                             | (151)          | (146)           |    |    |
| Recoveries on receivables previously written off                    | 32             | 47              |    |    |
| Provision for credit losses                                         | 89             | 136             |    |    |
| Adjustment due to sale of receivables                               | (1)            | (3)             |    |    |
| Foreign currency translation adjustment                             | (21)           | (20)            |    |    |
| Balance at end of period                                            | 336            | 388             |    |    |
| **Allowance for Credit Losses**                                     |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 82      | 75      |
| Collectively evaluated for impairment                               |           |            | 254     | 313     |
| Allowance, Ending Balance                                           | 388            | 374             | 336     | 388     |
| **Recorded Investment in Finance Receivables**                      |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 565     | 614     |
| Collectively evaluated for impairment                               |           |            | 19,243  | 20,454  |
| Recorded Investment in Finance Receivables, Ending Balance          |           |            | 19,808  | 21,068  |
| Dealer                                                              |           |            |    |    |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Allowance for credit losses                                         | 10             | 10              | 9       | 10      |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Balance at beginning of year                                        | 10             | 10              |    |    |
| Receivables written off                                             | 0              | 0               |    |    |
| Recoveries on receivables previously written off                    | 0              | 0               |    |    |
| Provision for credit losses                                         | (1)            | 0               |    |    |
| Adjustment due to sale of receivables                               | 0              | 0               |    |    |
| Foreign currency translation adjustment                             | 0              | 0               |    |    |
| Balance at end of period                                            | 9              | 10              |    |    |
| **Allowance for Credit Losses**                                     |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 0       | 0       |
| Collectively evaluated for impairment                               |           |            | 9       | 10      |
| Allowance, Ending Balance                                           | 10             | 10              | 9       | 10      |
| **Recorded Investment in Finance Receivables**                      |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 0       | 0       |
| Collectively evaluated for impairment                               |           |            | 5,246   | 5,169   |
| Recorded Investment in Finance Receivables, Ending Balance          |           |            | 5,246   | 5,169   |
| Caterpillar Purchased Receivables                                   |           |            |    |    |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Allowance for credit losses                                         | 3              | 3               | 3       | 3       |
| **Financing Receivable, Allowance for Credit Losses**               |           |            |    |    |
| Balance at beginning of year                                        | 3              | 3               |    |    |
| Receivables written off                                             | 0              | 0               |    |    |
| Recoveries on receivables previously written off                    | 0              | 0               |    |    |
| Provision for credit losses                                         | 0              | 0               |    |    |
| Adjustment due to sale of receivables                               | 0              | 0               |    |    |
| Foreign currency translation adjustment                             | 0              | 0               |    |    |
| Balance at end of period                                            | 3              | 3               |    |    |
| **Allowance for Credit Losses**                                     |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 0       | 0       |
| Collectively evaluated for impairment                               |           |            | 3       | 3       |
| Allowance, Ending Balance                                           | $ 3            | $ 3             | 3       | 3       |
| **Recorded Investment in Finance Receivables**                      |           |            |    |    |
| Individually evaluated for impairment                               |           |            | 0       | 0       |
| Collectively evaluated for impairment                               |           |            | 2,537   | 3,238   |
| Recorded Investment in Finance Receivables, Ending Balance          |           |            | $ 2,537 | $ 3,238 |

| X                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
-- None. No documentation exists for this element. --
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents the allowance for credit losses expressed as a percent of finance receivables which is net of unearned income.
+ References
No definition available.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of gain (loss) from converting allowance reserve for credit loss to currency of reporting entity from amount denominated or measured in a different currency.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of reduction of allowance reserve for credit loss arising from sale of loan and lease portfolios.
+ References
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| X                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A valuation allowance for financing receivables that are expected to be uncollectible.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The increase (decrease) in the allowance for credit losses related to financing receivables.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of recovery of financing receivables doubtful of collection that were previously charged off.
+ 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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| - Definition
Amount of direct write-downs of financing receivables charged against the allowance.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were collectively evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were individually evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related to estimated loss from loan and lease transactions.
+ References
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| X                                                                                                                                                                                  |
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