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Regulatory Requirements and Subsidiary Dividend Restrictions - Regulatory Capital Requirements (Details) $ in Millions | Sep. 30, 2020 USD ($)
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StoneX Financial [Member] |
Capital and Other Regulatory Requirements [Line Items] |
Cash and securities segregated under commodity exchange act regulation | $ 3,089.9
Secured funds | 162.6
Minimum regulatory requirement | 3,030.6
Secured funds required under commodity exchange act | 150.1
Gain Capital Group, LLC [Member] |
Capital and Other Regulatory Requirements [Line Items] |
Cash and securities segregated under commodity exchange act regulation | 340.4
Secured funds | 4.3
Minimum regulatory requirement | 319.8
Secured funds required under commodity exchange act | 2.5
StoneX Financial Ltd. [Member] |
Capital and Other Regulatory Requirements [Line Items] |
Cash and securities segregated under commodity exchange act regulation | 516.5
Minimum regulatory requirement | 505.6
Gain Capital U.K. Ltd [Member] |
Capital and Other Regulatory Requirements [Line Items] |
Cash and securities segregated under commodity exchange act regulation | 206.9
Minimum regulatory requirement | 205.6
StoneX Financial Pte. Ltd. [Member] |
Capital and Other Regulatory Requirements [Line Items] |
Cash and securities segregated under commodity exchange act regulation | 340.6
Minimum regulatory requirement | $ 338.9

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- Definition Capital and Other Regulatory Requirements [Line Items] + References No definition available. + Details
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- Definition Cash and Securities Segregated under Commodity Exchange Act Regulation, Amount Required to be Segregated + References No definition available. + Details
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