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Commitments and Contingencies (Details) $ in Millions | Nov. 16, 2018 account | Dec. 31, 2020 USD ($) | Oct. 01, 2020 USD ($)
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Loss Contingencies [Line Items] |  |  |
Loss contingency, range of possible loss, portion not accrued |  | $ 29.0 |
Maximum amount of individual accounts receivable account |  | 1.4 |
Self insurance reserve |  | $ 1.2 |
Cumulative Effect, Period of Adoption, Adjustment |  |  |
Loss Contingencies [Line Items] |  |  |
Retained earnings, before tax |  |  | $ 8.2
StoneX Financial |  |  |
Loss Contingencies [Line Items] |  |  |
Number of accounts | account | 300 |  |

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