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Allowance for Credit Losses - By Loan Class (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | $ 157,069 | $ 125,972 | $ 125,972
Losses charged to allowance | (27,824) | (2,033) |
Recoveries credited to allowance | 575 | 1,031 |
Net losses charged to allowance | (27,249) | (1,002) |
Provision (credit) charged to operations | 12,978 | 8,587 |
Balance at the end of the period | 142,798 | 133,557 | 157,069
Commercial, financial and agricultural | Commercial. |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Charge-down due to customer filing bankruptcy | 25,600 |  |
Impact on credit loss expense due to customer filing bankruptcy | 4,400 |  |
Commercial, financial and agricultural | Domestic | Commercial. |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 35,550 | 26,728 | 26,728
Losses charged to allowance | (27,741) | (1,971) | (9,664)
Recoveries credited to allowance | 555 | 625 |
Net losses charged to allowance | (27,186) | (1,346) |
Provision (credit) charged to operations | 18,312 | 2,406 |
Balance at the end of the period | 26,676 | 27,788 | 35,550
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 42,703 | 36,474 | 36,474
Recoveries credited to allowance | 4 | 5 |
Net losses charged to allowance | 4 | 5 |
Provision (credit) charged to operations | (3,305) | 77 |
Balance at the end of the period | 39,402 | 36,556 | 42,703
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 5,088 | 3,794 | 3,794
Provision (credit) charged to operations | (1,320) | 190 |
Balance at the end of the period | 3,768 | 3,984 | 5,088
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 55,291 | 44,684 | 44,684
Recoveries credited to allowance |  | 311 |
Net losses charged to allowance |  | 311 |
Provision (credit) charged to operations | (194) | 5,938 |
Balance at the end of the period | 55,097 | 50,933 | 55,291
Real estate - mortgage | Domestic | Residential: first lien |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 5,812 | 4,759 | 4,759
Losses charged to allowance | (45) |  | (43)
Recoveries credited to allowance | 2 | 7 |
Net losses charged to allowance | (43) | 7 |
Provision (credit) charged to operations | (12) | (207) |
Balance at the end of the period | 5,757 | 4,559 | 5,812
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 11,024 | 8,284 | 8,284
Losses charged to allowance |  | (1) | (298)
Recoveries credited to allowance | 9 | 77 |
Net losses charged to allowance | 9 | 76 |
Provision (credit) charged to operations | (385) | (3) |
Balance at the end of the period | 10,648 | 8,357 | 11,024
Consumer | Domestic |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 318 | 281 | 281
Losses charged to allowance | (38) | (61) | (179)
Recoveries credited to allowance | 5 | 6 |
Net losses charged to allowance | (33) | (55) |
Provision (credit) charged to operations | 28 | 65 |
Balance at the end of the period | 313 | 291 | 318
Foreign. | Foreign |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at the beginning of the period | 1,283 | 968 | 968
Provision (credit) charged to operations | (146) | 121 |
Balance at the end of the period | $ 1,137 | $ 1,089 | $ 1,283

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