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Investment Securities - Narrative (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021 | Jan. 01, 2021
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Schedule of Available for sale Securities and Held to maturity Securities [Line Items] |  |  |
Accrued interest on investment securities | $ 26,000 | $ 26,800 |
Allowance for credit losses | 245 | 245 |
Carrying value of securities pledged as collateral | 831,800 | 873,200 |
Securities sold under repurchase agreements | 174,500 | 175,100 |
State and municipal |  |  |
Schedule of Available for sale Securities and Held to maturity Securities [Line Items] |  |  |
Allowance for credit losses | 245 | 245 |
State and municipal | Cumulative effect of ASC 326 adoption |  |  |
Schedule of Available for sale Securities and Held to maturity Securities [Line Items] |  |  |
Allowance for credit losses |  |  | $ 245
U.S. Government-sponsored mortgage-backed securities |  |  |
Schedule of Available for sale Securities and Held to maturity Securities [Line Items] |  |  |
Allowance for credit losses | $ 0 | $ 0 |

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