XML 54 R42.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Basis of Presentation and Consolidation and Accounting Standards Adopted (Details) $ / shares in Units, $ in Millions |  |  | 3 Months Ended |
--- | --- | --- | --- | ---
Nov. 07, 2023 | Oct. 31, 2022 USD ($) | Dec. 31, 2023 USD ($) country client $ / shares | Dec. 31, 2022 USD ($) | Sep. 30, 2023 $ / shares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Number of countries over entity operates (more than) | country |  |  | 180 |  |
Number of commercial and institutional clients (more than) | client |  |  | 54,000 |  |
Number retail clients (over) | client |  |  | 400,000 |  |
Stock split, conversion ratio | 1.5 |  |  |  |
Common stock - par value (in dollar per share) | $ / shares |  |  | $ 0.01 |  | $ 0.01
Gain on acquisition |  |  | $ 0.0 | $ 23.5 |
Cotton Distributors Inc. |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Fair value of identifiable net assets acquired |  | $ 66.2 |  |  |
Purchase price |  | $ 42.7 |  |  |
Gain on acquisition |  |  |  | $ 23.5 |
Retail Segment |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Number of countries over entity operates (more than) | country |  |  | 180 |  |

X
- Definition Number of Commercial and Institutional Clients + References No definition available. + Details
Name: | intl_NumberOfCommercialAndInstitutionalClients
Namespace Prefix: | intl_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Retail Clients + References No definition available. + Details
Name: | intl_NumberRetailClients
Namespace Prefix: | intl_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479637/805-30-30-6 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479637/805-30-30-5 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479668/805-30-25-2 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479668/805-30-25-3 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479668/805-30-25-4 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (f)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479581/805-30-50-1 + Details
Name: | us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 30 -Paragraph 8 -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479637/805-30-30-8 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479581/805-30-50-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 30 -Paragraph 7 -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479637/805-30-30-7 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479303/805-10-55-37 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479907/805-20-50-1 + Details
Name: | us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 808 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479402/808-10-50-1 + Details
Name: | us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of countries in which the entity operates as of balance sheet date. + References No definition available. + Details
Name: | us-gaap_NumberOfCountriesInWhichEntityOperates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB TOPIC 4.C) -SubTopic 10 -Topic 505 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480008/505-10-S99-4 + Details
Name: | us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=intl_CottonDistributorsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=intl_RetailSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |