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Recent Accounting Pronouncements - Impact of ASC (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments | $ 218 |  |  |  |  |
Allowance for credit losses | 36,290 | $ 35,696 | $ 31,146 | $ 30,968 | $ 31,373 | $ 31,572
Unallocated |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 953 | 1,727 | 268 | 952 | 1,052 | 1,180
Commercial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 25,992 | 24,424 | 23,292 | 22,523 | 22,045 | 22,084
Commercial | Commercial and industrial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 8,577 | 7,813 | 9,158 | 8,921 | 10,333 | 8,925
Commercial | Real estate construction |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 4,709 | 3,646 | 1,446 | 1,332 | 878 | 783
Commercial | Commercial real estate |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 12,706 | 12,965 | 12,688 | 12,270 | 10,834 | 12,376
Consumer |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 9,345 | 9,545 | 7,586 | 7,493 | 8,276 | 8,308
Consumer | Other revolving and installment |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 251 | 293 | 528 | 537 | 634 | 481
Real estate first mortgage | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 7,757 | 7,901 | 5,769 | 5,591 | 6,175 | 6,532
Real estate junior lien | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses | 1,337 | $ 1,351 | 1,289 | $ 1,365 | $ 1,467 | $ 1,295
Unfunded commitments |  |  |  |  |  |
Liabilities [Abstract] |  |  |  |  |  |
Off balance sheet liability, Allowance for loan losses | 5,200 |  | 3,244 |  |  |
Mortgage backed securities - Residential agency |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments | $ 103 |  |  |  |  |
Accounting Standards Update 2016-13 | Unfunded commitments |  |  |  |  |  |
Liabilities [Abstract] |  |  |  |  |  |
Off balance sheet liability, Allowance for loan losses |  |  | 1,900 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | 172 |  |  |
Allowance for credit losses on loans and investments securities |  |  | 35,175 |  |  |
Allowance for credit losses |  |  | 35,003 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Unallocated |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 984 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Commercial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 24,524 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Commercial | Commercial and industrial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 8,296 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Commercial | Real estate construction |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 3,964 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Commercial | Commercial real estate |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 12,264 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Consumer |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 9,495 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Consumer | Other revolving and installment |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 424 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Real estate first mortgage | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 7,849 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Real estate junior lien | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 1,222 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Unfunded commitments |  |  |  |  |  |
Liabilities [Abstract] |  |  |  |  |  |
Off balance sheet liability, Allowance for loan losses |  |  | 5,159 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Obligations of state and political agencies |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | 110 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2016-13 | Mortgage backed securities - Residential agency |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | 62 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | 172 |  |  |
Allowance for credit losses on loans and investments securities |  |  | 4,029 |  |  |
Allowance for credit losses |  |  | 3,857 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Unallocated |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 716 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Commercial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 1,232 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Commercial | Commercial and industrial |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | (862) |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Commercial | Real estate construction |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 2,518 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Commercial | Commercial real estate |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | (424) |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Consumer |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 1,909 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Consumer | Other revolving and installment |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | (104) |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Real estate first mortgage | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | 2,080 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Real estate junior lien | Consumer | Residential |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses |  |  | (67) |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Unfunded commitments |  |  |  |  |  |
Liabilities [Abstract] |  |  |  |  |  |
Off balance sheet liability, Allowance for loan losses |  |  | 1,915 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Obligations of state and political agencies |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | 110 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Mortgage backed securities - Residential agency |  |  |  |  |  |
Investment Securities |  |  |  |  |  |
Allowance for credit losses on investments |  |  | $ 62 |  |  |

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