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Loans - Schedule of Allowance for Credit Losses for Loans Held for Investment (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Interest Receivable | $ 56.7 |  | $ 56.7 |  | $ 46.7
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 146.1 | $ 74.2 | 73.0 | $ 73.0 |
Provision for Credit Loss Expense | 5.2 | 2.6 | 53.7 | 10.1 |
Loans Charged-Off | (6.4) | (4.7) | (15.1) | (16.3) |
Recoveries Collected |  | 2.9 |  | 8.2 |
Ending balance | 145.5 | 75.0 | 145.5 | 75.0 |
Financing Receivable, Allowance for Credit Loss, Recovery | 1.8 |  | 5.1 |  |
Real Estate |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance |  | 27.7 |  | 31.0 |
Provision for Credit Loss Expense |  | 0.4 |  | (1.3) |
Loans Charged-Off |  | (0.3) |  | (3.3) |
Recoveries Collected |  | 0.8 |  | 2.2 |
Ending balance |  | 28.6 |  | 28.6 |
Consumer |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance |  | 9.1 |  | 8.7 |
Provision for Credit Loss Expense |  | 2.7 |  | 7.1 |
Loans Charged-Off |  | (2.8) |  | (9.1) |
Recoveries Collected |  | 0.8 |  | 3.1 |
Ending balance |  | 9.8 |  | 9.8 |
Commercial Portfolio Segment [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance |  | 35.7 |  | 31.3 |
Provision for Credit Loss Expense |  | (0.4) |  | 4.3 |
Loans Charged-Off |  | (1.6) |  | (3.5) |
Recoveries Collected |  | 1.3 |  | 2.9 |
Ending balance |  | 35.0 |  | 35.0 |
Agricultural |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance |  | 1.7 |  | 2.0 |
Provision for Credit Loss Expense |  | (0.1) |  | 0.0 |
Loans Charged-Off |  | 0.0 |  | (0.4) |
Recoveries Collected |  | 0.0 |  | 0.0 |
Ending balance |  | $ 1.6 |  | $ 1.6 |
Commercial Real Estate Non Owner Occupied Loans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 23.6 |  | 8.8 |  |
Provision for Credit Loss Expense | 1.5 |  | 11.4 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 25.2 |  | 25.2 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.1 |  | 0.1 |  |
Agricultural Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 0.9 |  | 1.6 |  |
Provision for Credit Loss Expense | 0.0 |  | 0.0 |  |
Loans Charged-Off | 0.0 |  | (0.1) |  |
Ending balance | 0.9 |  | 0.9 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.0 |  |
Commercial and Floor Plans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 41.0 |  | 25.5 |  |
Provision for Credit Loss Expense | 1.2 |  | 20.0 |  |
Loans Charged-Off | (3.3) |  | (4.7) |  |
Ending balance | 36.7 |  | 36.7 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 1.0 |  |
Commercial Real Estate Owner Occupied [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 19.1 |  | 10.0 |  |
Provision for Credit Loss Expense | 0.1 |  | 5.7 |  |
Loans Charged-Off | (0.2) |  | (0.3) |  |
Ending balance | 19.1 |  | 19.1 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.1 |  | 0.2 |  |
Commercial Real Estate Multi-family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 8.5 |  | 0.7 |  |
Provision for Credit Loss Expense | 2.3 |  | 3.2 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 10.8 |  | 10.8 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.0 |  |
Commercial real estate |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 51.2 |  | 19.5 |  |
Provision for Credit Loss Expense | 3.9 |  | 20.3 |  |
Loans Charged-Off | (0.2) |  | (0.3) |  |
Ending balance | 55.1 |  | 55.1 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 0.3 |  |
Land Acquisition And Development Construction Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 1.5 |  | 1.9 |  |
Provision for Credit Loss Expense | 0.5 |  | 0.3 |  |
Loans Charged-Off | 0.0 |  | (0.5) |  |
Ending balance | 1.2 |  | 1.2 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 0.2 |  |
Residential construction |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 1.3 |  | 1.5 |  |
Provision for Credit Loss Expense | 0.3 |  | 1.0 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 1.6 |  | 1.6 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.0 |  |
Commercial construction |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 6.3 |  | 2.7 |  |
Provision for Credit Loss Expense | 0.8 |  | 3.1 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 7.1 |  | 7.1 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.0 |  |
Construction Loans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 9.1 |  | 6.1 |  |
Provision for Credit Loss Expense | 0.6 |  | 3.8 |  |
Loans Charged-Off | 0.0 |  | (0.5) |  |
Ending balance | 9.9 |  | 9.9 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 0.2 |  |
Residential Real Estate 1-4 Family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 10.3 |  | 1.8 |  |
Provision for Credit Loss Expense | 1.1 |  | 3.3 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 9.2 |  | 9.2 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.1 |  |
Home Equity Line of Credit [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 1.5 |  | 1.0 |  |
Provision for Credit Loss Expense | 0.0 |  | 0.1 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 1.5 |  | 1.5 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.1 |  |
Residential Real Estate [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 11.8 |  | 2.8 |  |
Provision for Credit Loss Expense | 1.1 |  | 3.4 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 10.7 |  | 10.7 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.2 |  |
Agricultural Real Estate Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 3.1 |  | 0.5 |  |
Provision for Credit Loss Expense | 0.2 |  | 0.6 |  |
Loans Charged-Off | 0.0 |  | 0.0 |  |
Ending balance | 2.9 |  | 2.9 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.0 |  |
Real Estate Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 75.2 |  | 28.9 |  |
Provision for Credit Loss Expense | 3.2 |  | 21.3 |  |
Loans Charged-Off | (0.2) |  | (0.8) |  |
Ending balance | 78.6 |  | 78.6 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.4 |  | 0.7 |  |
Consumer Indirect Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 16.4 |  | 4.5 |  |
Provision for Credit Loss Expense | 0.7 |  | 5.1 |  |
Loans Charged-Off | (0.8) |  | (3.2) |  |
Ending balance | 17.0 |  | 17.0 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.7 |  | 1.8 |  |
Direct consumer |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 5.1 |  | 2.9 |  |
Provision for Credit Loss Expense | 0.6 |  | 1.3 |  |
Loans Charged-Off | (1.1) |  | (3.1) |  |
Ending balance | 4.8 |  | 4.8 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 0.7 |  |
Credit Card Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 2.0 |  | 2.5 |  |
Provision for Credit Loss Expense | 0.6 |  | 1.0 |  |
Loans Charged-Off | (0.6) |  | (2.2) |  |
Ending balance | 2.2 |  | 2.2 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.2 |  | 0.6 |  |
Consumer |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 23.5 |  | 9.9 |  |
Provision for Credit Loss Expense | 1.9 |  | 7.4 |  |
Loans Charged-Off | (2.5) |  | (8.5) |  |
Ending balance | 24.0 |  | 24.0 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 1.1 |  | 3.1 |  |
Commercial Purpose secured by 1-4 Family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 5.1 |  | 5.9 |  |
Provision for Credit Loss Expense | 0.2 |  | 2.8 |  |
Loans Charged-Off | 0.0 |  | (0.1) |  |
Ending balance | 5.0 |  | 5.0 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.1 |  | 0.2 |  |
Commercial Borrower [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 0.4 |  | 1.2 |  |
Provision for Credit Loss Expense | 0.3 |  | 1.0 |  |
Loans Charged-Off | (0.4) |  | (0.9) |  |
Ending balance | 0.3 |  | 0.3 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.0 |  | 0.1 |  |
Commercial Portfolio Segment [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Beginning balance | 46.5 |  | 32.6 |  |
Provision for Credit Loss Expense | 1.1 |  | 23.8 |  |
Loans Charged-Off | (3.7) |  | (5.7) |  |
Ending balance | 42.0 |  | 42.0 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 0.3 |  | 1.3 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 30.0 |  | 30.0 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Real Estate Non Owner Occupied Loans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 4.9 |  | 4.9 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Agricultural Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (0.6) |  | (0.6) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial and Floor Plans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (5.1) |  | (5.1) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Real Estate Owner Occupied [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 3.5 |  | 3.5 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Real Estate Multi-family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 6.9 |  | 6.9 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial real estate |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 15.3 |  | 15.3 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Land Acquisition And Development Construction Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (0.1) |  | (0.1) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Residential construction |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (0.9) |  | (0.9) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial construction |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 1.3 |  | 1.3 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Construction Loans [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 0.3 |  | 0.3 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Residential Real Estate 1-4 Family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 10.6 |  | 10.6 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Home Equity Line of Credit [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 0.5 |  | 0.5 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Residential Real Estate [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 11.1 |  | 11.1 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Agricultural Real Estate Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 1.8 |  | 1.8 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Real Estate Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 28.5 |  | 28.5 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Consumer Indirect Financing Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 8.8 |  | 8.8 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Direct consumer |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 3.0 |  | 3.0 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 0.3 |  | 0.3 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Consumer |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | 12.1 |  | 12.1 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Purpose secured by 1-4 Family [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (3.8) |  | (3.8) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Borrower [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (1.1) |  | (1.1) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Ending balance | (10.0) |  | (10.0) |  |
Loans And Leases Held For Investment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Interest Receivable | $ 45.7 |  | $ 45.7 |  |

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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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