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Capital and Other Regulatory Requirements - Regulatory Capital Requirements (Details) $ in Millions | Mar. 31, 2018 USD ($)
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FCStone LLC [Member] |
Net Capital under Commodity Exchange Act Computation | $ 152.3
Required Net Capital under Commodity Exchange Act | 83.6
Cash and Securities Segregated under Commodity Exchange Act Regulation | 2,357.1
Cash and Securities Segregated under Commodity Exchange Act Regulation, Amount Required to be Segregated | 2,303.2
Secured Funds | 144.0
Secured Funds Required Under Commodity Exchange Act | 128.3
Sterne Agee Clearing, Inc. [Member] |
Net Capital under Commodity Exchange Act Computation | 1.9
Required Net Capital under Commodity Exchange Act | 0.1
Sterne Agee, and Leach, Inc [Member] |
Net Capital under Commodity Exchange Act Computation | 3.9
Required Net Capital under Commodity Exchange Act | 0.4
INTL FCStone Ltd [Member] |
Net Capital under Commodity Exchange Act Computation | 193.6
Required Net Capital under Commodity Exchange Act | 90.3
Cash and Securities Segregated under Commodity Exchange Act Regulation | 183.4
Cash and Securities Segregated under Commodity Exchange Act Regulation, Amount Required to be Segregated | 183.4
INTL Netherlands BV [Member] |
Net Capital under Commodity Exchange Act Computation | 192.9
Required Net Capital under Commodity Exchange Act | 90.3
INTL FCStone DTVM Ltda [Member] |
Net Capital | 12.9
Capital Required for Capital Adequacy | 2.3
Gainvest S.A. Sociedad Gerente de FCI - Comision Nacional de Valores [Member] |
Net Capital under Commodity Exchange Act Computation | 2.8
Required Net Capital under Commodity Exchange Act | 0.1
Net Capital | 4.8
Capital Required for Capital Adequacy | 0.1
INTL Capital S.A. – General Inspector of Justice [Member] [Domain] |
Net Capital under Commodity Exchange Act Computation | 5.2
Required Net Capital under Commodity Exchange Act | 0.8
INTL Capital S.A. – Superintendence of Securities Markets of Buenos Aires [Member] [Domain] |
Net Capital under Commodity Exchange Act Computation | 1.1
Required Net Capital under Commodity Exchange Act | 0.4
Customer Reserve Requirement [Member] [Member] |
Cash Reserve Deposit Required and Made | 0.7
Cash Reserve Deposit Required | 0.0
PAB Reserve Requirement [Member] |
Cash Reserve Deposit Required and Made | 5.5
Cash Reserve Deposit Required | $ 2.7

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- Definition The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Rule 15c3-1 -Number 240 -Section 15c3-1 + Details
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