Investment Securities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Interest Receivable	$ 38	$ 40
Floating rate securities	3	4
Repositioned U.S. Treasury securities	(827)
Net securities losses	(19)	$ 0	$ 0
Carrying value of securities pledged	7,000
Pledged to the FHLB as collateral for potential future borrowings - investment securities	6,000
Collateral for potential future borrowings	1,000
Liabilities secured by pledged collateral	357
Debt securities
Securities losses	$ (19)

Floating rate securities

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- Definition

Liabilities, primarily public and other deposits of state and local government agencies and derivative instruments, secured by pledged securities.

+ References

No definition available.

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- Definition

Pledged to the FHLB as collateral for potential future borrowings - investment securities

+ References

No definition available.

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- Definition

Repositioning lower-yielding treasury securities

+ References

No definition available.

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- Definition

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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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- Definition

Amount of liability associated with securities borrowed from entities in exchange for collateral.

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