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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Income Tax Disclosure [Abstract] |  |  |  |
Effective income tax rate | 24.20% | 23.10% | 6.30% | 23.00%
CIT Group Inc. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Deferred tax liabilities | $ 297 |  | $ 297 |

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