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Loans Held for Investment - Schedule of Loans by Segment (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2023 | Dec. 31, 2020
Loans and Leases Receivable |  |  |
Loans and Leases Receivable, Deferred Income | $ (15.6) | $ (12.5) |
Loans and Leases Receivable, Net of Deferred Income | 18,099.2 | 18,279.6 |
Accounts Receivable, Allowance for Credit Loss | (220.1) | (227.7) | $ (144.3)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 122.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (59.5) |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (74.6) |  | (54.8)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 43.9 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (37.6) |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 8,528.6 | 8,869.2 |
Residential Real Estate Construction Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (3.6) |  | (1.6)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 2.4 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Commercial Real Estate Construction [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (31.2) |  | (7.3)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 6.0 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (0.2) |  |
Real Estate Construction Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1,944.4 | 1,826.5 |
Residential Mortgage [Member] |  |  |
Loans and Leases Receivable |  |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 2,188.3 | 2,244.3 |
Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (5.9) |  | (2.7)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 1.9 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (2.3) |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 794.9 | 716.8 |
Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (138.7) | (160.1) | (80.5)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 69.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (43.6) |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 13,456.2 | 13,656.8 |
Indirect consumer |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (15.3) |  | (16.7)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 14.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 829.7 | 740.9 |
Other consumer |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (5.2) |  | (4.6)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 4.6 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 152.9 | 141.6 |
Credit card consumer |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (2.8) |  | (2.6)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 2.2 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 75.9 | 76.5 |
Total consumer loans |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (23.3) | (13.0) | (23.9)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 21.1 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1,058.5 | 959.0 |
Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (54.9) | (50.2) | (39.2)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 31.6 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (11.4) |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 2,882.6 | 2,906.8 |
Agricultural Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (3.2) | (4.4) | (0.7)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 0.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (4.5) |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 708.3 | 769.4 |
Other, including overdrafts |  |  |
Loans and Leases Receivable |  |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 9.2 | 0.1 |
Loans held for investment |  |  |
Loans and Leases Receivable |  |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 18,114.8 | $ 18,292.1 |
Non Owner Occupied Loans |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (27.2) |  | (25.5)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 17.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (17.2) |  |
Commercial Real Estate Owner Occupied |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (19.5) |  | (18.3)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 13.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (9.5) |  |
Commercial Real Estate Multifamily |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (27.9) |  | (11.0)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 13.3 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (10.9) |  |
Land Acquisition And Development Construction Financing Receivable [Member] |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (1.3) |  | (1.3)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 0.5 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (3.4) |  |
Construction Loans |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (36.1) |  | (10.2)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 8.9 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (3.6) |  |
Residential Real Estate 1-4 Family |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (20.5) |  | (11.4)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 13.4 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (0.1) |  |
Home Equity Loan |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (1.6) |  | (1.4)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 1.2 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 0.0 |  |
Residential Real Estate |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (22.1) |  | (12.8)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 14.6 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (0.1) |  |
Commercial and Floor Plans |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (49.0) |  | (34.2)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 27.1 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (11.2) |  |
Commercial Purpose Secured by 1-4 Family |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (5.7) |  | (4.7)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 4.4 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (0.2) |  |
Commercial Borrower |  |  |
Loans and Leases Receivable |  |  |
Accounts Receivable, Allowance for Credit Loss | (0.2) |  | $ (0.3)
Accounts Receivable, Allowance for Credit Loss, Beginning Balance | 0.1 |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | $ 0.0 |  |

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