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Capital and Other Regulatory Requirements - Regulatory Capital Requirements (Details) $ in Millions | Dec. 31, 2020 USD ($)
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Capital and Other Regulatory Requirements [Abstract] |
Adjusted net capital | $ 5.0
StoneX Financial Inc. |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Actual | 253.2
Minimum Requirement | 146.8
StoneX Financial Ltd. |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Actual | 308.4
Minimum Requirement | 142.2
Gain Capital Group, LLC |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Actual | 76.4
Minimum Requirement | 31.3
Gain Capital U.K. Ltd. |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Actual | 169.4
Minimum Requirement | $ 66.7

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- Definition Capital and Other Regulatory Requirements [Abstract] + References No definition available. + Details
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- Definition Minimum amount of net capital required to be maintained by broker-dealer subsidiary to engage in security transaction, calculated under Aggregate Indebtedness Standard. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Rule 15c3-1 -Number 240 -Section 15c3-1 + Details
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- Definition Amount of adjusted net capital of futures commission merchant (FCM) per Commodity Futures Trading Commission's (CFTC) requirement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher CFTC -Name Rule 17 -Number 1 -Section 17 -Paragraph (a) -Subparagraph (5) + Details
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- Definition Amount of net capital required to be maintained by futures commission merchant (FCM) per Commodity Futures Trading Commission's (CFTC) requirement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher CFTC -Name Rule 17 -Number 1 -Section 17 -Paragraph (a) -Subparagraph (1)(i) + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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