FAIR VALUE (Schedule of Assets and Liabilities Measured at Fair Value by Class on a Recurring Basis Using Level 3 Inputs) (Details) - Level 3 - Fair Value, Recurring - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Private equity investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of assets, beginning balance	$ 210	$ 116	$ 157	$ 105
Unrealized securities gains, net	(5)	12	40	36
Other noninterest income	0	0	0	0
Purchases	7	7	16	12
Cost of investments sold	0	0	(1)	(6)
Transfers out	0	0	0	(12)
Fair value of assets, ending balance	212	135	212	135
Ag loan servicing
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of assets, beginning balance	18	20	18	20
Unrealized securities gains, net	0	0	0	0
Other noninterest income	0	(1)	0	(1)
Purchases	0	0	0	0
Cost of investments sold	0	0	0	0
Transfers out	0	0	0	0
Fair value of assets, ending balance	$ 18	$ 19	$ 18	$ 19

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Noninterest Income

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