XML 132 R74.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Physical Commodities Inventory - LCM Adjustments (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Sep. 30, 2014
--- | --- | ---
Physical Commodities Inventory [Abstract] |  |
Inventory Adjustments | $ 0.3 | $ 1.0

X
- Definition Physical Commodities Inventory [Abstract] + References No definition available. + Details
Name: | intl_PhysicalCommoditiesInventoryAbstract
Namespace Prefix: | intl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Certain changes made in the current period to the value and amount of inventory reported. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360613&loc=d3e4492-108314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_InventoryAdjustments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant