Investment Securities - Narrative (Details)	3 Months Ended
Mar. 31, 2025 USD ($) security	Dec. 31, 2024 USD ($)
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Number of investment securities in a loss position for less than twelve months \| security	35
Number of investment securities in a loss position for twelve months or longer \| security	209
AFS allowance for credit loss	$ 0
Held-to-maturity, allowance for credit loss, measurement input	0
Debt securities, available-for-sale, realized gain	0
Debt securities, available-for-sale, realized loss	0
Collateral Pledged
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
AFS pledged to secure deposits	3,350,000,000	$ 2,830,000,000
HTM pledged to secure deposits	$ 2,290,000,000	$ 2,450,000,000

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount of allowance for credit 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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).

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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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