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Loans Held for Investment - Schedule of Modifications to Borrowers (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 69.6 | $ 40.0 | $ 97.9 | $ 65.9 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.38% | 0.22% | 0.54% | 0.36% |
Interest Receivable | $ 126.4 |  | $ 126.4 |  | $ 129.1
Financing Receivable, Loan in Process | 1.2 |  | 1.2 |  |
Financing Receivable, Modified in Period, Accrued Interest, Amount |  |  | 0.8 | $ 0.9 |
Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | $ 0.0 | 0.0 | 1.7 |
Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 46.5 | 40.0 | 68.9 | 64.2 |
Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 23.1 | 0.0 | 29.0 | 0.0 |
Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.0 | 0.0 | 1.6 |
Agricultural |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 5.7 |  | $ 11.7 | $ 1.1 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.79% |  | 1.62% | 0.15% |
Financing Receivable, Loan in Process | $ 4.1 |  | $ 4.1 |  | 1.8
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 7 years 1 month 6 days |  | 7 years | 7 years 2 months 12 days |
Agricultural | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 |  | $ 0.0 | $ 0.0 |
Agricultural | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 5.7 |  | 11.7 | 1.1 |
Agricultural | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 |  | 0.0 | 0.0 |
Agricultural | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 |  | $ 0.0 | $ 0.0 |
Agricultural | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months | 0 years |  | 0 years | 0 years |
Agricultural | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 0.00% |  | 0.00% | 0.00% |
Agricultural |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 45.6 | $ 19.6 | $ 46.3 | $ 36.6 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 6.53% | 2.85% | 6.63% | 5.32% |
Financing Receivable, Loan in Process | $ 2.0 |  | $ 2.0 |  | 3.1
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 4 years 1 month 6 days | 8 years 10 months 24 days | 4 years 1 month 6 days | 9 years 2 months 12 days |
Agricultural | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Agricultural | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 22.8 | 19.6 | 23.5 | 36.6 |
Agricultural | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 22.8 | 0.0 | 22.8 | 0.0 |
Agricultural | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Agricultural | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months | 55 years 2 months 12 days | 0 years | 55 years 2 months 12 days | 0 years |
Agricultural | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 1.20% | 0.00% | 1.20% | 0.00% |
Other, including overdrafts |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Loan in Process | $ 0.0 |  | $ 0.0 |  | 0.0
Commercial |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 6.3 | $ 13.9 | $ 17.5 | $ 19.0 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.07% | 0.16% | 0.19% | 0.22% |
Financing Receivable, Loan in Process | $ 6.5 |  | $ 6.5 |  | 18.8
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 11 years 7 months 6 days | 6 years 4 months 24 days | 7 years 2 months 12 days | 6 years 4 months 24 days |
Commercial | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 1.6 |
Commercial | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 6.3 | 13.9 | 17.5 | 17.4 |
Commercial | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.0 | 0.0 | 0.0 |
Commercial | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 1.3 |
Commercial | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months | 0 years | 0 years | 0 years | 0 years |
Commercial | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 0.00% | 0.00% | 0.00% | 0.00% |
Total construction loans |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | $ 0.1 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent |  |  |  | 0.01% |
Financing Receivable, Loan in Process | $ 2.3 |  | $ 2.3 |  | 3.5
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  |  |  | 12 years 4 months 24 days |
Total construction loans | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | $ 0.0 |
Total construction loans | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | 0.1 |
Total construction loans | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | 0.0 |
Total construction loans | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | $ 0.0 |
Total construction loans | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months |  |  |  | 0 years |
Total construction loans | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent |  |  |  | 0.00% |
Residential |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.3 | $ 0.1 | $ 0.4 | $ 0.3 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.01% | 0.00% | 0.02% | 0.01% |
Financing Receivable, Loan in Process | $ 8.7 |  | $ 8.7 |  | 15.6
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 0 years | 16 years 2 months 12 days | 11 years | 19 years 6 months |
Residential | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.1 |
Residential | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.1 | 0.1 | 0.2 |
Residential | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.3 | 0.0 | 0.3 | 0.0 |
Residential | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.3 |
Residential | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months | 31 years 2 months 12 days | 0 years | 31 years 2 months 12 days | 0 years |
Residential | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 3.40% | 0.00% | 3.40% | 0.00% |
Total real estate |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 12.3 | $ 14.0 | $ 29.6 | $ 20.5 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.09% | 0.10% | 0.22% | 0.15% |
Financing Receivable, Loan in Process | $ 21.6 |  | $ 21.6 |  | 39.7
Total real estate | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | $ 0.0 | 0.0 | $ 1.7 |
Total real estate | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 12.0 | 14.0 | 29.3 | 18.8 |
Total real estate | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.3 | 0.0 | 0.3 | 0.0 |
Total real estate | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.0 | 0.0 | 1.6 |
Commercial |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 11.7 | $ 6.4 | $ 21.9 | $ 8.8 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.38% | 0.21% | 0.72% | 0.29% |
Financing Receivable, Loan in Process | $ 13.9 |  | $ 13.9 |  | 15.9
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 7 years 9 months 18 days | 8 years 3 months 18 days | 7 years 9 months 18 days | 9 years |
Commercial | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Commercial | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 11.7 | 6.4 | 16.0 | 8.8 |
Commercial | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.0 | 5.9 | 0.0 |
Commercial | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Commercial | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months | 0 years | 0 years | 5 years | 0 years |
Commercial | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 0.00% | 0.00% | 1.00% | 0.00% |
Indirect consumer |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Loan in Process | $ 9.0 |  | $ 9.0 |  | 10.6
Direct and advance lines |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 0.1 |  |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent |  |  | 0.07% |  |
Financing Receivable, Loan in Process | 0.8 |  | $ 0.8 |  | 1.1
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  |  | 10 years 1 month 6 days |  |
Direct and advance lines | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 0.0 |  |
Direct and advance lines | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | 0.1 |  |
Direct and advance lines | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | 0.0 |  |
Direct and advance lines | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 0.0 |  |
Direct and advance lines | Weighted-Average Months of Term Extension |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period, Term Extension, Weighted-Average Months |  |  | 0 years |  |
Direct and advance lines | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent |  |  | 0.00% |  |
Credit Card Receivable [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Loan in Process | 1.7 |  | $ 1.7 |  | 1.8
Total consumer loans |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 0.1 |  |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent |  |  |  |  |
Financing Receivable, Loan in Process | $ 11.5 |  | $ 11.5 |  | $ 13.5
Total consumer loans | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | 0.0 |  |
Total consumer loans | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | 0.1 |  |
Total consumer loans | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | 0.0 |  |
Total consumer loans | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 0.0 |  |

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