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Investment Securities - Narrative (Details) shares in Thousands, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) security shares | Dec. 31, 2021 USD ($) | Dec. 31, 2022 USD ($) security shares | Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items] |  |  |  |
Debt securities, available-for-sale, accrued Interest | $ 33.0 | $ 22.0 | $ 33.0 | $ 22.0
Debt Securities, held-to-maturity, accrued interest | 19.0 | 7.0 | 19.0 | 7.0
Write off of accrued interest receivable | $ 0.0 | 0.0 | $ 0.0 | 0.0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 151 |  | 151 |
Debt securities, held-to-maturity, threshold period past due | 30 days |  | 30 days |
Securities past due | $ 10,279.0 | 3,809.0 | $ 10,279.0 | 3,809.0
Held-to-maturity securities, nonaccrual | 0.0 | 0.0 | 0.0 | 0.0
Federal Home Loan Bank stock | 197.0 | 40.0 | 197.0 | 40.0
Nonmarketable equity securities | 58.0 | 1.0 | 58.0 | 1.0
Amortization method qualified affordable housing project investments | 598.0 | 157.0 | 598.0 | 157.0
Total Past Due |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Securities past due | 0.0 | 0.0 | 0.0 | 0.0
Asset Pledged as Collateral |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment securities, aggregate carrying value, pledged as collateral | $ 4,200.0 | $ 5,700.0 | $ 4,200.0 | $ 5,700.0
Visa, Inc | Class B Common Stock |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment owned (in shares) | shares | 354 |  | 354 |
U.S. government and government agency securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 144 |  | 144 |
Corporate bonds |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 7 |  | 7 |

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