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INCOME TAXES - Schedule of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Balance at beginning of period | $ 31 | $ 30 | $ 31
Additions for tax positions related to current year | 8 | 0 | 0
Additions for tax positions related to prior years | 48 | 5 | 1
Reductions for tax positions of prior years | 0 | 0 | (2)
Expiration of statutes of limitations | (1) | (2) | (1)
Settlements | 0 | (2) | (5)
Balance at end of period | 86 | 31 | 30
CIT Group Inc. |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Effect of CIT Merger | 0 | 0 | $ 6
Liabilities for Unrecognized Tax Benefits |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Balance at beginning of period | 28 |  |
Additions for tax positions related to current year | 8 |  |
Additions for tax positions related to prior years | 42 |  |
Reductions for tax positions of prior years | 0 |  |
Expiration of statutes of limitations | (1) |  |
Settlements | 0 |  |
Balance at end of period | 77 | 28 |
Liabilities for Unrecognized Tax Benefits | CIT Group Inc. |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Effect of CIT Merger | 0 |  |
Interest / Penalties |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Balance at beginning of period | 3 |  |
Additions for tax positions related to current year | 0 |  |
Additions for tax positions related to prior years | 6 |  |
Reductions for tax positions of prior years | 0 |  |
Expiration of statutes of limitations | 0 |  |
Settlements | 0 |  |
Balance at end of period | 9 | $ 3 |
Interest / Penalties | CIT Group Inc. |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Effect of CIT Merger | $ 0 |  |

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