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Loans Held for Investment - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense | $ 32.2 | $ 82.7 | $ (14.6) |
Less loans charged-off | (35.9) | (45.0) | (16.6) |
Recoveries Collected | 12.4 | 14.9 | 9.3 |
Accounts Receivable, Allowance for Credit Loss | 227.7 | 220.1 | 122.3 | $ 144.3
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 31.1 | 68.4 | (14.7) |
Non Owner Occupied Loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | (4.2) | (8.3) |
Less loans charged-off |  | (3.5) | 0.0 |
Recoveries Collected |  | 0.4 | 0.1 |
Accounts Receivable, Allowance for Credit Loss |  | 27.2 | 17.3 | 25.5
Commercial Real Estate Owner Occupied |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | (2.7) | (2.7) |
Less loans charged-off |  | (2.5) | (2.3) |
Recoveries Collected |  | 1.9 | 0.0 |
Accounts Receivable, Allowance for Credit Loss |  | 19.5 | 13.3 | 18.3
Commercial Real Estate Multifamily |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 8.7 | 2.3 |
Less loans charged-off |  | (5.7) | 0.0 |
Recoveries Collected |  | 0.7 | 0.0 |
Accounts Receivable, Allowance for Credit Loss |  | 27.9 | 13.3 | 11.0
Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 1.8 | (8.7) |
Less loans charged-off | (7.6) | (11.7) | (2.3) |
Recoveries Collected |  | 3.0 | 0.1 |
Accounts Receivable, Allowance for Credit Loss |  | 74.6 | 43.9 | 54.8
Land Acquisition And Development Construction Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | (0.4) | (0.1) |
Less loans charged-off |  | (2.6) | (1.2) |
Recoveries Collected |  | 0.4 | 0.5 |
Accounts Receivable, Allowance for Credit Loss |  | 1.3 | 0.5 | 1.3
Residential Real Estate Construction Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 1.1 | 0.9 |
Less loans charged-off |  | 0.0 | (0.1) |
Recoveries Collected |  | 0.1 | 0.0 |
Accounts Receivable, Allowance for Credit Loss |  | 3.6 | 2.4 | 1.6
Commercial Real Estate Construction [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 31.6 | (1.3) |
Less loans charged-off |  | (6.6) | (0.1) |
Recoveries Collected |  | 0.0 | 0.1 |
Accounts Receivable, Allowance for Credit Loss |  | 31.2 | 6.0 | 7.3
Construction Loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 32.3 | (0.5) |
Less loans charged-off |  | (9.2) | (1.4) |
Recoveries Collected |  | 0.5 | 0.6 |
Accounts Receivable, Allowance for Credit Loss |  | 36.1 | 8.9 | 10.2
Residential Real Estate 1-4 Family |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 6.9 | 2.0 |
Less loans charged-off |  | (0.2) | 0.0 |
Recoveries Collected |  | 0.3 | 0.0 |
Accounts Receivable, Allowance for Credit Loss |  | 20.5 | 13.4 | 11.4
Residential Real Estate |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 6.9 | 1.6 |
Less loans charged-off | (0.6) | (0.3) | (0.1) |
Recoveries Collected |  | 0.8 | 0.3 |
Accounts Receivable, Allowance for Credit Loss |  | 22.1 | 14.6 | 12.8
Agricultural Real Estate Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 1.5 | (0.1) |
Less loans charged-off | 0.0 | (0.2) | (0.7) |
Recoveries Collected |  | 0.4 | 0.0 |
Accounts Receivable, Allowance for Credit Loss |  | 5.9 | 1.9 | 2.7
Real Estate Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense | 35.2 | 42.5 | (7.7) |
Less loans charged-off | (18.5) | (21.4) | (4.5) |
Recoveries Collected | 4.7 | 4.7 | 1.0 |
Accounts Receivable, Allowance for Credit Loss | 160.1 | 138.7 | 69.3 | 80.5
Indirect consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 2.7 | (1.4) |
Less loans charged-off | (7.3) | (4.0) | (3.5) |
Recoveries Collected |  | 2.3 | 2.5 |
Accounts Receivable, Allowance for Credit Loss |  | 15.3 | 14.3 | 16.7
Other consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 2.2 | 1.7 |
Less loans charged-off | (4.1) | (3.7) | (2.9) |
Recoveries Collected |  | 2.1 | 1.2 |
Accounts Receivable, Allowance for Credit Loss |  | 5.2 | 4.6 | 4.6
Credit card consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 2.4 | 0.6 |
Less loans charged-off | (2.6) | (2.4) | (1.8) |
Recoveries Collected |  | 0.6 | 0.8 |
Accounts Receivable, Allowance for Credit Loss |  | 2.8 | 2.2 | 2.6
Total consumer loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense | (1.0) | 7.3 | 0.9 |
Less loans charged-off | (14.0) | (10.1) | (8.2) |
Recoveries Collected | 4.7 | 5.0 | 4.5 |
Accounts Receivable, Allowance for Credit Loss | 13.0 | 23.3 | 21.1 | 23.9
Commercial and Floor Plans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 15.1 | (7.3) |
Less loans charged-off |  | (6.6) | (3.0) |
Recoveries Collected |  | 2.2 | 3.2 |
Accounts Receivable, Allowance for Credit Loss |  | 49.0 | 27.1 | 34.2
Commercial Purpose Secured by 1-4 Family |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 1.2 | (0.5) |
Less loans charged-off |  | (0.2) | (0.3) |
Recoveries Collected |  | 0.1 | 0.5 |
Accounts Receivable, Allowance for Credit Loss |  | 5.7 | 4.4 | 4.7
Commercial Borrower |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 1.4 | 0.1 |
Less loans charged-off |  | (1.3) | (0.4) |
Recoveries Collected |  | 0.0 | 0.1 |
Accounts Receivable, Allowance for Credit Loss |  | 0.2 | 0.1 | 0.3
Commercial Portfolio Segment [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense | (3.9) | 17.7 | (7.7) |
Less loans charged-off | (3.4) | (8.1) | (3.7) |
Recoveries Collected | 2.6 | 2.3 | 3.8 |
Accounts Receivable, Allowance for Credit Loss | 50.2 | 54.9 | 31.6 | 39.2
Agricultural Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense | 0.8 | 0.9 | (0.2) |
Less loans charged-off | 0.0 | (5.4) | (0.2) |
Recoveries Collected | 0.4 | 2.9 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | $ 4.4 | 3.2 | 0.3 | 0.7
Home Equity Loan |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | 0.0 | (0.4) |
Less loans charged-off |  | (0.1) | (0.1) |
Recoveries Collected |  | 0.5 | 0.3 |
Accounts Receivable, Allowance for Credit Loss |  | $ 1.6 | $ 1.2 | $ 1.4

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