| **Consolidated Statements of Comprehensive Income - USD ($) $ in Millions**            | 3 Months Ended | 9 Months Ended |
|----------------------------------------------------------------------------------------|----------------|----------------|
||
| **Statement of Comprehensive Income [Abstract]**                                       |           |           |   |   |
| Profit of consolidated companies                                                       | $ 98           | $ 109          | $ 303 | $ 348 |
| **Other comprehensive income (loss), net of tax:**                                     |           |           |   |   |
| Foreign currency translation, net of tax (expense)/benefit                             | (5)            | (206)          | 100 | (472) |
| **Derivative financial instruments:**                                                  |           |           |   |   |
| Gains (losses) deferred, net of tax (expense)/benefit                                  | (10)           | (1)            | (15) | 0 |
| (Gains) losses reclassified to earnings, net of tax expense/(benefit)                  | 7              | 1              | 13 | 3 |
| **Available-for-sale securities:**                                                     |           |           |   |   |
| Gains (losses) deferred, net of tax (expense)/benefit                                  | 1              | 0              | (1) | 0 |
| (Gains) losses reclassified to earnings, net of tax expense/(benefit)                  | 0              | 0              | 0 | 0 |
| Total Other comprehensive income (loss), net of tax                                    | (7)            | (206)          | 97 | (469) |
| Comprehensive income (loss)                                                            | 91             | (97)           | 400 | (121) |
| Less: Comprehensive income (loss) attributable to the noncontrolling interests         | 1              | (6)            | 2 | (3) |
| Comprehensive income (loss) attributable to Caterpillar Financial Services Corporation | $ 90           | $ (91)         | $ 398 | $ (118) |

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| - Definition
Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.
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| - Definition
Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.
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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.
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Amount after tax and reclassification adjustments of other comprehensive income (loss).
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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.
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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).
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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).
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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.
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| - Definition
The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.
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