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v3.23.1

Investment Securities (Narrative) (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 USD ($) Security | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) Security
Schedule Of Investments [Line Items] |  |  |
Securities pledged as collateral | $ 891,500,000 |  | $ 850,400,000
Sales of securities available for sale | $ 0 | $ 0 |
Number of security positions, unrealized loss position | Security | 222 |  | 226
Number of security positions, unrealized loss position for more than 12 months | Security | 189 |  | 127
Securities, 12 months or longer, Fair Value | $ 935,964,000 |  | $ 760,210,000
Securities, 12 months or longer, Unrealized Losses | $ 158,232,000 |  | $ 155,102,000
Number of security positions, unrealized loss position for less than 12 months | Security | 33 |  | 99
Securities, Less than 12 months, Fair Value | $ 9,112,000 |  | $ 193,800,000
Securities, Less than 12 months, Unrealized Losses | 520,000 |  | 17,922,000
Available for sale securities, allowance for credit loss | 0 |  | 0
Securities held to maturity, Amortized Cost | 180,057,000 |  | 188,980,000
Investment securities, nonaccrual | 8,797,000 |  | 10,197,000
Municipal Bonds [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Securities held to maturity, Amortized Cost | 87,300,000 |  | 90,600,000
Internally rated held-to-maturity securities | 6,000,000.0 |  | 6,900,000
Held To Maturity Securities Non Rated | 400,000 |  |
Available for Sale Securities [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Accrued interest receivable | 2,000,000.0 |  | 2,100,000
Held To Maturity Investment Securities [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Accrued interest receivable | 1,000,000.0 |  | 695,000
Investment securities, nonaccrual | 0 |  | $ 0
Held To Maturity Investment Securities [Member] | Maximum [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Credit loss expense | $ 1,000 | $ 1,000 |

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