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ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Schedule of Changes in Components of AOCI (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | $ 22,228 | $ 21,255
AOCI activity before reclassifications | 249 |
Amounts reclassified from AOCI to earnings | (3) |
Other comprehensive income (loss), net of tax | 246 | (91)
Ending balance, shareholders' equity | 22,295 | 21,848
Total accumulated other comprehensive loss |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | (445) | (491)
Other comprehensive income (loss), net of tax | 246 | (91)
Ending balance, shareholders' equity | (199) | (582)
Unrealized loss on securities available for sale |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | (584) | (577)
AOCI activity before reclassifications | 239 |
Amounts reclassified from AOCI to earnings | 0 |
Other comprehensive income (loss), net of tax | 239 | (91)
Ending balance, shareholders' equity | (345) | (668)
Unrealized loss on securities available for sale transferred to held to maturity |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | (4) | (5)
AOCI activity before reclassifications | 0 |
Amounts reclassified from AOCI to earnings | 0 |
Other comprehensive income (loss), net of tax | 0 | 0
Ending balance, shareholders' equity | (4) | (5)
Defined benefit pension items |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | 135 | 91
AOCI activity before reclassifications | 0 |
Amounts reclassified from AOCI to earnings | 0 |
Other comprehensive income (loss), net of tax | 0 | 0
Ending balance, shareholders' equity | 135 | 91
Unrealized gain on cash flow hedge derivatives |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning balance, shareholders' equity | 8 | 0
AOCI activity before reclassifications | 10 | 0
Amounts reclassified from AOCI to earnings | (3) | 0
Other comprehensive income (loss), net of tax | 7 | 0
Ending balance, shareholders' equity | $ 15 | $ 0

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