| **Credit Commitments (Details) $ in Millions**                           | 1 Months Ended | 12 Months Ended |         |        |
|--------------------------------------------------------------------------|----------------|-----------------|---------|--------|
||
| **Line of Credit Facility**                                              |           |            |    |   |
| Number of global credit facilities                                       |           | 3               |    |   |
| Amount available                                                         |           | $ 10,500        |    |   |
| Maximum borrowing capacity from Caterpillar, Variable lending agreements |           | 2,440           |    |   |
| Maximum lending capacity to Caterpillar, Variable lending agreements     |           | $ 2,140         |    |   |
| Termination, minimum number of days to notify                            |           | 30 days         |    |   |
| Term lending agreements, maximum remaining maturity                      |           | 10 years        |    |   |
| Other assets                                                             |           | $ 1,182         | $ 1,098 |   |
| Caterpillar                                                              |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Maximum borrowing capacity from Caterpillar, Variable lending agreements |           | 2,440           |    |   |
| Maximum lending capacity to Caterpillar, Variable lending agreements     |           | 2,140           |    |   |
| Notes payable                                                            |           | 10              | 24      | $ 23   |
| Revolving credit facilities                                              |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount outstanding                                                       |           | 0               |    |   |
| Revolving credit facilities | Cat Financial                              |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         |           | 7,750           |    |   |
| 364-day facility                                                         |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 3,150        |            |    |   |
| 364-day facility | Credit Facility 1                                     |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Term                                                                     | 364 days       |            |    |   |
| 364-day facility | Cat Financial                                         |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 2,330        |            |    |   |
| Three-year facility                                                      |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 2,730        |            |    |   |
| Three-year facility | Credit Facility 1                                  |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Term                                                                     | 3 years        |            |    |   |
| Three-year facility | Cat Financial                                      |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 2,010        |            |    |   |
| Five-year facility                                                       |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 4,620        |            |    |   |
| Five-year facility | Credit Facility 1                                   |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Term                                                                     | 5 years        |            |    |   |
| Five-year facility | Cat Financial                                       |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         | $ 3,410        |            |    |   |
| Credit lines with banks                                                  |           |            |    |   |
| **Line of Credit Facility**                                              |           |            |    |   |
| Amount available                                                         |           | 3,450           |    |   |
| Amount outstanding                                                       |           | $ 687           | $ 853   |   |

| X                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents the number of global credit facilities.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum borrowing capacity under the variable lending agreements with parent entity.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum lending capacity under variable lending agreements to parent entity.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents the maximum remaining maturity of outstanding term lending agreements.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Variable Lending Agreement, Termination, Minimum Number Of Days To Notify
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
No definition available.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.
+ 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of assets classified as other.
+ References
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| X                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                   |
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| X                                                                                                                                                   |
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| X                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                    |
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| X                                                                                                                                             |
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