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Securities - Narrative (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($)
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Fair value of debt securities from AFS to HTM | $ 3,010,000,000.00 |  |  |
Unrealized losses, net of tax, from transfer of AFS to HTM | $ 113,000,000 | $ 113,000,000 |  |
AFS and HTM, accrued interest |  | $ 41,800,000 | $ 33,100,000 |
Number of available-for-sale debt securities in an unrealized loss position | security |  | 559 | 431 |
Allowance for credit loss |  | $ 0 | $ 0 |
Provision for credit losses |  | 0 | 0 | $ 0
HTM securities allowance for credit loss |  | 0 |  |
Amortized Cost |  | 9,881,093,000 |  |
Asset Pledged as Collateral |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Amortized Cost |  | $ 794,200,000 | $ 803,900,000 |
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security |  | 263 | 180 |
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security |  |  | 50 |
U.S. Treasury securities |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security |  | 15 | 21 |
Corporate debt securities |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security |  | 68 | 30 |
Non-agency mortgage-backed securities |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security |  | 100 |  |

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