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Loans Held for Investment - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024 | Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Recoveries Collected | $ 1.8 | $ 2.6 |  |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 20.2 | 8.4 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest | 215.3 | 227.7 | $ 204.1 | $ 227.7
Financing Receivable, Allowance for Credit Loss, Writeoff | 10.8 | 11.0 | 114.7 |
Provision for Loan, Lease, and Other Losses | 20.0 | 5.3 |  |
Commercial real estate |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Financing Receivable, Allowance for Credit Loss, Writeoff |  |  | 25.4 |
Agricultural |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Recoveries Collected | 0.0 | 0.3 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest | 7.1 | 4.2 | 9.0 | 4.4
Financing Receivable, Allowance for Credit Loss, Writeoff | 2.9 | 0.0 | 0.3 |
Provision for Loan, Lease, and Other Losses | 1.0 | (0.5) |  |
Residential |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.3 |  | 1.0 |
Total real estate |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Recoveries Collected | 0.1 | 0.7 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest | 146.0 | 152.9 | 139.4 | 160.1
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.3 | 3.2 | 39.6 |
Provision for Loan, Lease, and Other Losses | 6.8 | (4.7) |  |
Indirect consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Financing Receivable, Allowance for Credit Loss, Writeoff | 2.7 |  | 8.5 |
Total consumer loans |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Recoveries Collected | 1.2 | 1.0 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest | 15.9 | 12.6 | 16.8 | 13.0
Financing Receivable, Allowance for Credit Loss, Writeoff | 4.7 | 3.8 | 15.4 |
Provision for Loan, Lease, and Other Losses | 2.6 | 2.4 |  |
Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Recoveries Collected | 0.5 | 0.6 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest | 46.3 | 58.0 | 38.9 | $ 50.2
Financing Receivable, Allowance for Credit Loss, Writeoff | 2.9 | 4.0 | $ 59.4 |
Provision for Loan, Lease, and Other Losses | $ 9.8 | $ 11.2 |  |

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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- Definition Amount of increase in allowance for credit loss on financing receivable from recovery. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (c)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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- Definition Amount of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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