| **Financing Activities (Details 3) (USD $)In Millions, unless otherwise specified** | 3 Months Ended | 12 Months Ended |
|-------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Financing Receivable, Allowance for Credit Losses**                               |           |            |
| Balance at beginning of year                                                        | $ 378          | $ 426           |
| Receivables written off                                                             | (52)           | (179)           |
| Recoveries on receivables previously written off                                    | 14             | 56              |
| Provision for credit losses                                                         | 33             | 84              |
| Adjustment due to sale of receivables                                               |           | (3)             |
| Foreign currency translation adjustment                                             |           | (6)             |
| Balance at end of period                                                            | 373            | 378             |
| **Allowance for Credit Losses**                                                     |           |            |
| Individually evaluated for impairment                                               | 50             | 70              |
| Collectively evaluated for impairment                                               | 323            | 308             |
| Allowance, Ending Balance                                                           | 373            | 378             |
| **Recorded Investment in Finance Receivables**                                      |           |            |
| Individually evaluated for impairment                                               | 555            | 629             |
| Collectively evaluated for impairment                                               | 29,245         | 28,473          |
| Recorded Investment in Finance Receivables, Ending Balance                          | 29,800         | 29,102          |
| Customer                                                                            |           |            |
| **Financing Receivable, Allowance for Credit Losses**                               |           |            |
| Balance at beginning of year                                                        | 365            | 414             |
| Receivables written off                                                             | (52)           | (179)           |
| Recoveries on receivables previously written off                                    | 14             | 56              |
| Provision for credit losses                                                         | 32             | 83              |
| Adjustment due to sale of receivables                                               |           | (3)             |
| Foreign currency translation adjustment                                             |           | (6)             |
| Balance at end of period                                                            | 359            | 365             |
| **Allowance for Credit Losses**                                                     |           |            |
| Individually evaluated for impairment                                               | 50             | 70              |
| Collectively evaluated for impairment                                               | 309            | 295             |
| Allowance, Ending Balance                                                           | 359            | 365             |
| **Recorded Investment in Finance Receivables**                                      |           |            |
| Individually evaluated for impairment                                               | 555            | 629             |
| Collectively evaluated for impairment                                               | 20,520         | 20,127          |
| Recorded Investment in Finance Receivables, Ending Balance                          | 21,075         | 20,756          |
| Dealer                                                                              |           |            |
| **Financing Receivable, Allowance for Credit Losses**                               |           |            |
| Balance at beginning of year                                                        | 10             | 9               |
| Receivables written off                                                             | 0              | 0               |
| Recoveries on receivables previously written off                                    | 0              | 0               |
| Provision for credit losses                                                         | 0              | 1               |
| Adjustment due to sale of receivables                                               |           | 0               |
| Foreign currency translation adjustment                                             |           | 0               |
| Balance at end of period                                                            | 10             | 10              |
| **Allowance for Credit Losses**                                                     |           |            |
| Individually evaluated for impairment                                               | 0              | 0               |
| Collectively evaluated for impairment                                               | 10             | 10              |
| Allowance, Ending Balance                                                           | 10             | 10              |
| **Recorded Investment in Finance Receivables**                                      |           |            |
| Individually evaluated for impairment                                               | 0              | 0               |
| Collectively evaluated for impairment                                               | 5,212          | 5,254           |
| Recorded Investment in Finance Receivables, Ending Balance                          | 5,212          | 5,254           |
| Caterpillar Purchased Receivables                                                   |           |            |
| **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                                                         | 1              | 0               |
| Adjustment due to sale of receivables                                               |           | 0               |
| Foreign currency translation adjustment                                             |           | 0               |
| Balance at end of period                                                            | 4              | 3               |
| **Allowance for Credit Losses**                                                     |           |            |
| Individually evaluated for impairment                                               | 0              | 0               |
| Collectively evaluated for impairment                                               | 4              | 3               |
| Allowance, Ending Balance                                                           | 4              | 3               |
| **Recorded Investment in Finance Receivables**                                      |           |            |
| Individually evaluated for impairment                                               | 0              | 0               |
| Collectively evaluated for impairment                                               | 3,513          | 3,092           |
| Recorded Investment in Finance Receivables, Ending Balance                          | $ 3,513        | $ 3,092         |

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| X                                                                                                                                                                                                                                                                                                                                                                 |
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| - Definition
Reduction to the allowance for credit losses related to adjustments due to sale of receivables.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Provision charged for the period based on estimated losses to be realized from loan and lease transactions, excluding miscellaneous other receivables.
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A valuation allowance for financing receivables that are expected to be uncollectible.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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| - Definition
Amount of recovery of financing receivables doubtful of collection that were previously charged off.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of direct write-downs of financing receivables charged against the allowance.
+ References
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| - Definition
The balance of financing receivables that were collectively evaluated for impairment.
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The balance of financing receivables that were individually evaluated for impairment.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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