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LONG-TERM DEBT AND SHAREHOLDERS' EQUITY (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |  |
Common stock, outstanding shares (in shares) | 147,640 |  | 147,640 |  | 147,871 |  |  |
Common stock, par value (in dollars per share) | $ 0.001 |  | $ 0.001 |  | $ 0.001 |  |  |
Common stock and additional paid in capital | $ 1,721 |  | $ 1,721 |  | $ 1,737 |  |  |
Accumulated other comprehensive loss | 6,865 | $ 6,385 | 6,865 | $ 6,385 | 6,124 | $ 6,596 | $ 6,025 | $ 5,691
Unrealized loss amortization associated with the securities transferred from AFS to HTM | 47 | 51 | 137 | 147 |  |  |  |
4.70% Fixed-To-Floating Senior Notes | Senior notes |  |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |  |
Debt instrument face amount | $ 500 |  | $ 500 |  |  |  |  |
Debt instrument stated interest rate | 4.70% |  | 4.70% |  |  |  |  |
Fixed-Rate Available For Sale Securities |  |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |  |
Unrealized loss amortization associated with the securities transferred from AFS to HTM, before tax |  |  | $ 1,700 |  | 1,800 |  |  |
Unrealized loss amortization associated with the securities transferred from AFS to HTM |  |  | 1,200 |  | 1,400 |  |  |
Accumulated other comprehensive income (loss) |  |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive loss | $ (2,056) | $ (2,336) | $ (2,056) | $ (2,336) | $ (2,380) | $ (2,164) | $ (2,549) | $ (2,692)

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