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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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INVESTMENT SECURITIES (Narrative) (Details)	3 Months Ended			6 Months Ended
INVESTMENT SECURITIES (Narrative) (Details)	Jun. 30, 2025 USD ($) security	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) security	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) security
Marketable Securities [Line Items]
Accrued interest receivable	$ 62,000,000			$ 62,000,000		$ 60,000,000
Investment securities	19,678,000,000			19,678,000,000		$ 20,270,000,000
Unrealized loss amortization associated with the securities transferred from AFS to HTM	$ 47,000,000		$ 50,000,000	$ 90,000,000	$ 96,000,000
Number of AFS investment securities in an unrealized loss position \| security	2,302			2,302		2,534
Available-for-sale, realized gain (loss)	$ 0		$ 0	$ 0	$ 0
Allowance for credit loss on HTM securities (less than)	1,000,000			1,000,000
Fixed-Rate Available For Sale Securities
Marketable Securities [Line Items]
Unrealized loss amortization associated with the securities transferred from AFS to HTM, before tax		$ 1,800,000,000		1,700,000,000
Unrealized loss amortization associated with the securities transferred from AFS to HTM		$ 1,400,000,000		1,300,000,000
Asset Pledged as Collateral
Marketable Securities [Line Items]
Investment securities	$ 17,700,000,000			$ 17,700,000,000		$ 17,900,000,000