Label	Element	Value
Non cash equivalent segregated assets	intl_NonCashEquivalentSegregatedAssets	$ 306,000,000.0
Non cash equivalent segregated assets	intl_NonCashEquivalentSegregatedAssets	13,000,000.0
Non cash equivalent segregated assets	intl_NonCashEquivalentSegregatedAssets	643,200,000
Non segregated cash and other non cash equivalent assets included with in deposits and receivables from broker dealers clearing organizations and counter parties	intl_NonSegregatedCashAndOtherNonCashEquivalentAssetsIncludedWithInDepositsAndReceivablesFromBrokerDealersClearingOrganizationsAndCounterParties	2,021,300,000
Non segregated cash and other non cash equivalent assets included with in deposits and receivables from broker dealers clearing organizations and counter parties	intl_NonSegregatedCashAndOtherNonCashEquivalentAssetsIncludedWithInDepositsAndReceivablesFromBrokerDealersClearingOrganizationsAndCounterParties	1,304,400,000
Non segregated cash and other non cash equivalent assets included with in deposits and receivables from broker dealers clearing organizations and counter parties	intl_NonSegregatedCashAndOtherNonCashEquivalentAssetsIncludedWithInDepositsAndReceivablesFromBrokerDealersClearingOrganizationsAndCounterParties	1,054,700,000
Deposits with and receivables from broker dealers, clearing organizations, and counterparties [Member]
Restricted Cash Equivalents	us-gaap_RestrictedCashEquivalents	467,900,000	[1]
Restricted Cash Equivalents	us-gaap_RestrictedCashEquivalents	288,700,000	[1]
Restricted Cash Equivalents	us-gaap_RestrictedCashEquivalents	909,900,000	[1]
Restricted Cash	us-gaap_RestrictedCash	711,900,000	[1]
Restricted Cash	us-gaap_RestrictedCash	947,400,000	[1]
Restricted Cash	us-gaap_RestrictedCash	698,700,000	[1]
Cash segregated under federal and other regulations [Member]
Cash Segregated under Commodity Exchange Act Regulation	us-gaap_CashSegregatedUnderCommodityExchangeActRegulation	1,907,200,000	[2]
Cash Segregated under Commodity Exchange Act Regulation	us-gaap_CashSegregatedUnderCommodityExchangeActRegulation	743,900,000	[2]
Cash Segregated under Commodity Exchange Act Regulation	us-gaap_CashSegregatedUnderCommodityExchangeActRegulation	765,500,000	[2]
Cash and Cash Equivalents [Member]
Cash and Cash Equivalents, at Carrying Value	us-gaap_CashAndCashEquivalentsAtCarryingValue	952,600,000
Cash and Cash Equivalents, at Carrying Value	us-gaap_CashAndCashEquivalentsAtCarryingValue	471,300,000
Cash and Cash Equivalents, at Carrying Value	us-gaap_CashAndCashEquivalentsAtCarryingValue	$ 342,300,000

[1] Represents segregated client cash and U.S. Treasury obligations on deposit with, or pledged to, exchange clearing organizations and other FCMs. Excludes non-segregated cash, segregated securities pledged to exchange-clearing organizations with original or acquired maturities greater than 90 days, and other assets of $2,021.3 million, $1,304.4 million, and $1,054.7 million as of September 30, 2020, 2019, and 2018, respectively, included within ‘Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net’ on the consolidated balance sheets.

[2] Represents segregated client cash held at third-party banks. Excludes segregated commodity warehouse receipts, segregated United States (“U.S.”) Treasury obligations with original or acquired maturities of greater than 90 days, and other assets of $13.0 million, $306.0 million, and $643.2 million as of September 30, 2020, 2019, and 2018, respectively, included within ‘Cash, securities and other assets segregated under federal and other regulations’ on the consolidated balance sheets.