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Loans Held for Investment - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | $ 232.8 | $ 224.6 | $ 227.7 | $ 220.1 | $ 220.1
Provision for credit losses | 19.8 | (0.1) | 34.1 | 26.8 |
Loans Charged-Off(2) | (29.1) | (6.2) | (56.4) | (29.2) |
Recoveries Collected | 1.7 | 5.1 | 7.1 | 10.5 |
Ending balance | 225.4 | 226.7 | 225.4 | 226.7 | 227.7
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 20.0 | 3.2 | 47.0 | 25.3 |
Commercial real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | (21.6) |  | (7.6)
Agricultural |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 5.4 | 2.7 | 4.4 | 3.2 | 3.2
Provision for credit losses | 0.3 | 0.5 | 1.0 | (0.4) |
Loans Charged-Off(2) | (0.3) | 0.0 | (0.3) | 0.0 | 0.0
Recoveries Collected | 0.0 | 0.0 | 0.3 | 0.4 |
Ending balance | 5.4 | 3.2 | 5.4 | 3.2 | 4.4
Residential |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | (0.7) |  | (0.6)
Agricultural |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | 0.0 |  | 0.0
Total real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 139.7 | 158.7 | 160.1 | 138.7 | 138.7
Provision for credit losses | 18.3 | 1.8 | 10.3 | 35.6 |
Loans Charged-Off(2) | (22.2) | (1.8) | (35.5) | (16.6) |
Recoveries Collected | 0.2 | 3.5 | 1.1 | 4.5 |
Ending balance | 136.0 | 162.2 | 136.0 | 162.2 | 160.1
Indirect consumer |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | (6.9) |  | (7.3)
Direct and advance lines |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | (2.9) |  | (4.1)
Credit card |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Loans Charged-Off(2) |  |  | (2.1) |  | (2.6)
Total consumer loans |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 18.5 | 13.7 | 13.0 | 23.3 | 23.3
Provision for credit losses | 1.5 | 1.8 | 12.5 | (3.7) |
Loans Charged-Off(2) | (4.1) | (3.7) | (11.9) | (10.4) |
Recoveries Collected | 1.3 | 1.1 | 3.6 | 3.7 |
Ending balance | 17.2 | 12.9 | 17.2 | 12.9 | 13.0
Commercial |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 69.2 | 49.5 | 50.2 | 54.9 | 54.9
Provision for credit losses | (0.1) | (0.9) | 23.2 | (6.2) |
Loans Charged-Off(2) | (2.5) | (0.7) | (8.7) | (2.2) | (3.4)
Recoveries Collected | 0.2 | 0.5 | 2.1 | 1.9 |
Ending balance | $ 66.8 | $ 48.4 | $ 66.8 | $ 48.4 | $ 50.2

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