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Loans Receivable (Write-Offs Segmented by Year of Assignment) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2026 | Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Write-offs | $ 0.0 | $ 0.0
Dealer Loans [Member] |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Write-offs | 0.0 | 0.0
Purchased Loans [Member] |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Write-offs | 0.0 | 0.0
Allowance for Credit Losses [Member] |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff | 116.8 | 100.7
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff | 83.3 | 51.3
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff | 68.0 | 81.7
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff | 53.7 | 52.2
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff | 35.8 | 41.5
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff | 2.7 | 2.0
Write-offs | 360.3 | 329.4
Allowance for Credit Losses [Member] | Dealer Loans [Member] |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff | 93.0 | 69.3
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff | 65.3 | 34.2
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff | 37.4 | 52.3
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff | 23.3 | 14.7
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff | 7.4 | 12.6
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff | 0.5 | 0.5
Write-offs | 226.9 | 183.6
Allowance for Credit Losses [Member] | Purchased Loans [Member] |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff | 23.8 | 31.4
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff | 18.0 | 17.1
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff | 30.6 | 29.4
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff | 30.4 | 37.5
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff | 28.4 | 28.9
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff | 2.2 | 1.5
Write-offs | $ 133.4 | $ 145.8

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