Securities - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Gross realized losses	$ 0	$ 935,000,000	$ 0	$ 948,000,000
Gross realized gains	0	$ 0	0	$ 0
Securities pledged to secure securities sold under repurchase agreements	$ 19,200,000,000		$ 19,200,000,000		$ 19,100,000,000

Debt Securities, Available For Sale And Held To Maturity, Pledged

No definition available.

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- Definition

Amount of realized gain 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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

+ Details

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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

+ Details

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- References

No definition available.

+ Details

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