Business Combination, Contingent Consideration, Liability Term

No definition available.

Name:	intl_BusinessCombinationContingentConsiderationLiabilityTerm
Namespace Prefix:	intl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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
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+ Details

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Balance Type:	na
Period Type:	duration

- 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

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_BusinessAcquisitionAxis=intl_IncommSASMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions - Incomm S.A.S.. (Details) - USD ($) $ in Millions	Feb. 03, 2023	Jun. 30, 2023	Sep. 30, 2022
Business Acquisition [Line Items]
Goodwill		$ 59.4	$ 58.2
Incomm S.A.S..
Business Acquisition [Line Items]
Consideration transferred	$ 0.2
Annual payment	$ 1.3
Contingent consideration, liability term	4 years
Goodwill	$ 1.3