Consolidated Income Statements (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Revenues:
Sales of physical commodities	$ 43,283.7	$ 67,514.7	$ 72,521.2
Trading gains, net	265.0	244.9	201.6
Commission and clearing fees	173.3	161.0	134.5
Consulting and management fees	35.1	27.9	22.7
Interest income	10.3	10.3	10.3
Other Income	0.9	0.5	1.0
Total revenues	43,768.3	67,959.3	72,891.3
Cost of sales of physical commodities	43,289.9	67,505.1	72,472.2
Operating revenues	478.4	454.2	419.1
Clearing and related expenses	110.1	105.4	75.6
Introducing broker commissions	40.5	31.0	24.0
Interest expense	12.5	11.6	11.3
Net operating revenues	315.3	306.2	308.2
Compensation and other expenses:
Compensation and benefits	201.6	202.4	176.6
Communication and data services	23.3	22.6	15.5
Occupancy and equipment rental	12.0	11.0	8.9
Professional fees	13.1	12.9	10.6
Travel and business development	10.7	11.2	8.9
Depreciation and amortization	8.0	7.2	4.7
Bad debts and impairments	0.8	1.5	6.2
Other	23.2	21.6	21.4
Total compensation and other expenses	292.7	290.4	252.8
Income from continuing operations, before tax	22.6	15.8	55.4
Income tax expense	3.3	3.1	20.9
Net income from continuing operations	19.3	12.7	34.5
Income from discontinued operations, net of tax	0	0	0.2
Net income	19.3	12.7	34.7
Add: Net loss attributable to noncontrolling interests	0	0.1	0.1
Net income attributable to INTL FCStone Inc. common stockholders	19.3	12.8	34.8
Basic earnings per share:
Income from continuing operations attributable to INTL FCStone Inc. common stockholders	$ 1.01	$ 0.67	$ 1.92
Income from discontinued operations attributable to INTL FCStone Inc. common stockholders	$ 0.00	$ 0.00	$ 0.01
Net income attributable to INTL FCStone Inc. common stockholders	$ 1.01	$ 0.67	$ 1.93
Diluted earnings per share:
Income from continuing operations attributable to INTL FCStone Inc. common stockholders	$ 0.97	$ 0.64	$ 1.82
Income from discontinued operations attributable to INTL FCStone Inc. common stockholders	$ 0.00	$ 0.00	$ 0.01
Net income attributable to INTL FCStone Inc. common stockholders	$ 0.97	$ 0.64	$ 1.83
Weighted-average number of common shares outstanding:
Basic	18,443,233	18,282,939	17,618,085
Diluted	19,068,497	19,156,899	18,567,454
Amounts attributable to INTL FCStone Inc. common stockholders:
Income from continuing operations, net of tax	19.3	12.8	34.6
Income from discontinued operations, net of tax	0	0	0.2
Net income attributable to INTL FCStone Inc. common stockholders	$ 19.3	$ 12.8	$ 34.8