XML 50 R38.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Accumulated Other Comprehensive Income (Loss) (Tables) | 3 Months Ended
--- | ---
Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Abstract] |
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | The following table summarizes the changes in accumulated other comprehensive loss, net for the three months ended December 31, 2017.
(in millions) |  | Foreign Currency Translation Adjustment |  | Pension Benefits Adjustment |  | Accumulated Other Comprehensive Loss
Balances as of September 30, 2017 |  | $ | (21.5 | ) |  | $ | (3.0 | ) |  | $ | (24.5 | )
Other comprehensive loss, net of tax |  | (2.2 | ) |  | — |  |  | (2.2 | )
Balances as of December 31, 2017 |  | $ | (23.7 | ) |  | $ | (3.0 | ) |  | $ | (26.7 | )

X
- Definition Accumulated Other Comprehensive Income (Loss) [Abstract] + References No definition available. + Details
Name: | intl_AccumulatedOtherComprehensiveIncomeLossAbstract
Namespace Prefix: | intl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
Name: | us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration