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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, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 31.2 | $ 69.6 | $ 50.6 | $ 97.9 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.19% | 0.38% | 0.31% | 0.54% |
Interest Receivable | $ 105.7 |  | $ 105.7 |  | $ 116.8
Financing Receivable, Loan in Process | 0.0 |  | 0.0 |  | 1.2
Financing Receivable, Modified in Period, Accrued Interest, Amount |  |  | 0.3 | $ 0.8 |
Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | $ 0.0 | 0.0 | 0.0 |
Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 31.1 | 46.5 | 48.1 | 68.9 |
Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.1 | 23.1 | 2.5 | 29.0 |
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 |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 5.1 | $ 5.7 | $ 5.2 | $ 11.7 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.80% | 0.79% | 0.82% | 1.62% |
Financing Receivable, Loan in Process | $ 6.4 |  | $ 6.4 |  | 10.4
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 6 years | 7 years 1 month 6 days | 6 years | 7 years |
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 | 5.1 | 5.7 | 5.2 | 11.7 |
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 | 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 | 0 years | 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% | 0.00% |
Agricultural |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 8.9 | $ 45.6 | $ 12.1 | $ 46.3 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 1.64% | 6.53% | 2.23% | 6.63% |
Financing Receivable, Loan in Process | $ 10.4 |  | $ 10.4 |  | 5.2
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 5 years 10 months 24 days | 4 years 1 month 6 days | 6 years 6 months | 4 years 1 month 6 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 | 8.9 | 22.8 | 10.7 | 23.5 |
Agricultural | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 22.8 | 1.4 | 22.8 |
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 | 0 years | 55 years 2 months 12 days | 7 years 3 months 18 days | 55 years 2 months 12 days |
Agricultural | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 0.00% | 1.20% | 1.00% | 1.20% |
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 | $ 13.2 | $ 6.3 | $ 15.0 | $ 17.5 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.15% | 0.07% | 0.17% | 0.19% |
Financing Receivable, Loan in Process | $ 5.4 |  | $ 5.4 |  | 7.7
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 14 years 4 months 24 days | 11 years 7 months 6 days | 13 years 6 months | 7 years 2 months 12 days |
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 | 13.2 | 6.3 | 14.2 | 17.5 |
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 | 0.8 | 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 | 13 years 3 months 18 days | 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% | 0.90% | 0.00% |
Total construction loans |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  | $ 11.5 |  |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent |  |  | 1.14% |  |
Financing Receivable, Loan in Process | $ 9.6 |  | $ 9.6 |  | 3.7
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  |  | 6 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 |  |  | 11.5 |  |
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 | $ 0.5 | $ 0.4 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent |  | 0.01% | 0.02% | 0.02% |
Financing Receivable, Loan in Process | 3.3 |  | $ 3.3 |  | 9.7
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  | 0 years | 22 years 3 months 18 days | 11 years |
Residential | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | $ 0.0 | $ 0.0 | $ 0.0 |
Residential | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | 0.0 | 0.3 | 0.1 |
Residential | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | 0.3 | 0.2 | 0.3 |
Residential | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | $ 0.0 | $ 0.0 | $ 0.0 |
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 | 84 years 9 months 18 days | 31 years 2 months 12 days |
Residential | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent |  | 3.40% | 2.20% | 3.40% |
Total real estate |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 18.3 | $ 12.3 | $ 32.2 | $ 29.6 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.15% | 0.09% | 0.26% | 0.22% |
Financing Receivable, Loan in Process | $ 24.7 |  | $ 24.7 |  | 31.5
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 | $ 0.0 |
Total real estate | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 18.3 | 12.0 | 31.2 | 29.3 |
Total real estate | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.0 | 0.3 | 1.0 | 0.3 |
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 | 0.0 |
Commercial |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | $ 4.0 | $ 11.7 | $ 6.3 | $ 21.9 |
Financing Receivable, Modification to Total Financing Receivables, Excluding Accrued Interest, Percent | 0.16% | 0.38% | 0.25% | 0.72% |
Financing Receivable, Loan in Process | $ 7.6 |  | $ 7.6 |  | 14.8
Financing Receivable, Modified, Weighted Average Term Increase from Modification | 8 years 1 month 6 days | 7 years 9 months 18 days | 9 years 8 months 12 days | 7 years 9 months 18 days |
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 | 3.9 | 11.7 | 6.2 | 16.0 |
Commercial | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period | 0.1 | 0.0 | 0.1 | 5.9 |
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 | 23 years 7 months 6 days | 0 years | 22 years 4 months 24 days | 5 years |
Commercial | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent | 0.20% | 0.00% | 0.50% | 1.00% |
Indirect consumer |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Loan in Process | $ 9.7 |  | $ 9.7 |  | 11.7
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  | 4 years 6 months |  | 4 years 10 months 24 days |
Indirect consumer | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | $ 0.0 |  | $ 0.0 |
Indirect consumer | 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 |
Indirect consumer | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent |  | 0.00% |  | 0.00% |
Credit Card Receivable [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Loan in Process | 0.0 |  | 0.0 |  | 2.2
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 |  |  |  | 0.01% |
Financing Receivable, Loan in Process | 10.9 |  | 10.9 |  | 15.0
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 |  | 0.0 |
Consumer Loan |  |  |  |  |
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 | $ 1.2 |  | $ 1.2 |  | $ 1.1
Financing Receivable, Modified, Weighted Average Term Increase from Modification |  | 5 years |  | 10 years 1 month 6 days |
Consumer Loan | Principal Forgiveness |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | $ 0.0 |
Consumer Loan | Extended Maturity [Member] |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | 0.1 |
Consumer Loan | Extended Maturity and Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  |  |  | 0.0 |
Consumer Loan | Principal Forgiven |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified Period |  | $ 0.0 |  | $ 0.0 |
Consumer Loan | 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 |
Consumer Loan | Weighted-Average Interest Rate Reduction |  |  |  |  |
Financing Receivable, Modifications to Borrowers [Line Items] |  |  |  |  |
Combination Term Extension and Interest Rate Reduction Percent |  | 0.00% |  | 0.00% |

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