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Allowance for Credit Losses (By Loan Class) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | $ 61,384 | $ 109,059 | $ 60,278 | $ 61,384
Losses charged to allowance |  |  | (9,024) | (9,574) | (22,928)
Recoveries credited to allowance |  |  | 2,384 | 2,629 | 2,979
Net (losses) recoveries charged to allowance |  |  | (6,640) | (6,945) | (19,949)
Credit loss expense |  |  | 7,955 | 45,379 | 18,843
Balance at the end of the period |  |  | 110,374 | 109,059 | 60,278
Nonperforming Financing Receivable [Member] |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Credit loss expense | $ (9,500) | (9,500) |  |  |
ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | 10,347 |
Balance at the end of the period |  |  |  |  | 10,347
Commercial, financial and agricultural | Domestic | Commercial. |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 12,596 | 21,908 | 11,145 | 12,596
Losses charged to allowance |  |  | (8,083) | (8,936) | (14,412)
Recoveries credited to allowance |  |  | 1,943 | 2,191 | 2,196
Net (losses) recoveries charged to allowance |  |  | (6,140) | (6,745) | (12,216)
Credit loss expense |  |  | 7,410 | 13,261 | 10,765
Balance at the end of the period |  |  | 23,178 | 21,908 | 11,145
Commercial, financial and agricultural | Domestic | Commercial. | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | 4,247 |
Balance at the end of the period |  |  |  |  | 4,247
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 19,353 | 30,000 | 16,533 | 19,353
Losses charged to allowance |  |  | (364) |  | (7,353)
Recoveries credited to allowance |  |  | 171 |  | 318
Net (losses) recoveries charged to allowance |  |  | (193) |  | (7,035)
Credit loss expense |  |  | 5,847 |  | 4,215
Balance at the end of the period |  |  | 35,654 | 30,000 | 16,533
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 1,808 | 5,051 | 1,786 | 1,808
Credit loss expense |  |  | (1,760) | 3,620 | (22)
Balance at the end of the period |  |  | 3,291 | 5,051 | 1,786
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | (355) |
Balance at the end of the period |  |  |  |  | (355)
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 15,123 | 37,612 | 18,152 | 15,123
Losses charged to allowance |  |  | (2) | (19) | (39)
Recoveries credited to allowance |  |  |  | 35 | 113
Net (losses) recoveries charged to allowance |  |  | (2) | 16 | 74
Credit loss expense |  |  | (2,220) | 6,053 | 2,955
Balance at the end of the period |  |  | 35,390 | 37,612 | 18,152
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | 13,391 |
Balance at the end of the period |  |  |  |  | 13,391
Obligations of states and political subdivisions | Domestic | Commercial real estate: farmland & commercial |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  | 30,000 | 16,533 |
Losses charged to allowance |  |  |  | (55) |
Recoveries credited to allowance |  |  |  | 117 |
Net (losses) recoveries charged to allowance |  |  |  | 62 |
Credit loss expense |  |  |  | 17,697 |
Balance at the end of the period |  |  |  | 30,000 | 16,533
Obligations of states and political subdivisions | Domestic | Commercial real estate: farmland & commercial | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | (4,292) |
Balance at the end of the period |  |  |  |  | (4,292)
Real estate - mortgage | Domestic | Residential: first lien |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 3,467 | 3,874 | 3,762 | 3,467
Losses charged to allowance |  |  | (373) | (160) | (201)
Recoveries credited to allowance |  |  | 60 | 21 | 26
Net (losses) recoveries charged to allowance |  |  | (313) | (139) | (175)
Credit loss expense |  |  | 512 | 1,831 | 470
Balance at the end of the period |  |  | 4,073 | 3,874 | 3,762
Real estate - mortgage | Domestic | Residential: first lien | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | (1,580) |
Balance at the end of the period |  |  |  |  | (1,580)
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 7,719 | 9,570 | 7,535 | 7,719
Losses charged to allowance |  |  | (25) | (124) | (435)
Recoveries credited to allowance |  |  | 164 | 186 | 286
Net (losses) recoveries charged to allowance |  |  | 139 | 62 | (149)
Credit loss expense |  |  | (1,955) | 2,402 | (35)
Balance at the end of the period |  |  | 7,754 | 9,570 | 7,535
Real estate - mortgage | Domestic | Residential Junior Lien | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | (429) |
Balance at the end of the period |  |  |  |  | (429)
Consumer | Domestic |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | 447 | 291 | 542 | 447
Losses charged to allowance |  |  | (176) | (280) | (487)
Recoveries credited to allowance |  |  | 46 | 69 | 40
Net (losses) recoveries charged to allowance |  |  | (130) | (211) | (447)
Credit loss expense |  |  | 111 | 185 | 542
Balance at the end of the period |  |  | 272 | 291 | 542
Consumer | Domestic | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | (225) |
Balance at the end of the period |  |  |  |  | (225)
Foreign. | Foreign |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  | $ 871 | 753 | 823 | 871
Losses charged to allowance |  |  | (1) |  | (1)
Recoveries credited to allowance |  |  |  | 10 |
Net (losses) recoveries charged to allowance |  |  | (1) | 10 | (1)
Credit loss expense |  |  | 10 | 330 | (47)
Balance at the end of the period |  |  | $ 762 | 753 | 823
Foreign. | Foreign | ASU 2016-13 | Adjustment |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Balance at the beginning of the period |  |  |  | $ (410) |
Balance at the end of the period |  |  |  |  | $ (410)

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- Definition Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (4) + Details
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