Investment Securities - Narrative (Details)	Dec. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Carrying value of securities pledged to secure public deposits, derivatives and other secured borrowings	$ 1,460,000,000	$ 1,110,000,000
Number of AFS debt securities in unrealized loss position \| security	408
Number of HTM debt securities in unrealized loss position \| security	94
Allowance for credit losses, HTM portfolio	$ 0	0
Allowance for credit losses, AFS portfolio	$ 0	$ 0

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).

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-Publisher FASB
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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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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