Consolidated Income Statements - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Sales of physical commodities	$ 40,961.6	$ 52,899.2	$ 31,830.3
Principal gains, net	892.0	622.2	415.8
Revenue from contract with customer	2,119.5	487.3	452.0
Interest income	102.4	130.9	198.9
Total revenues	42,534.2	54,139.6	32,897.0
Cost of sales of physical commodities	40,861.1	52,831.3	31,790.9
Operating revenues	1,673.1	1,308.3	1,106.1
Transaction-based clearing expenses	271.7	222.5	183.5
Introducing broker commissions	160.5	113.8	114.7
Interest expense	49.6	80.4	142.0
Interest expense on corporate funding	41.3	23.6	12.7
Net operating revenues	1,150.0	868.0	653.2
Compensation and other expenses:
Compensation and benefits	679.1	518.7	393.1
Trading systems and market information	58.8	46.3	38.8
Professional fees	40.9	30.2	21.0
Non-trading technology and support	46.0	28.4	20.1
Occupancy and equipment rental	34.2	23.5	19.4
Selling and marketing	33.3	12.2	5.2
Travel and business development	4.5	8.9	16.2
Communications	9.3	7.0	6.6
Depreciation and amortization	36.5	19.7	14.0
Bad debts, net of recoveries and impairment	10.4	18.7	2.5
Recovery of bad debt on physical coal	0.0	0.0	(12.4)
Other	46.3	29.6	23.2
Total compensation and other expenses	999.3	743.2	547.7
Gain on acquisitions and other gains	3.4	81.9	5.5
Income from operations, before tax	154.1	206.7	111.0
Income tax expense	37.8	37.1	25.9
Net income	$ 116.3	$ 169.6	$ 85.1
Earnings per share:
Basic (in dollar per share)	$ 5.90	$ 8.78	$ 4.46
Diluted (in dollar per share)	$ 5.74	$ 8.61	$ 4.39
Weighted-average number of common shares outstanding:
Basic (in shares)	19,130,643	18,824,328	18,738,905
Diluted (in shares)	19,678,168	19,180,479	19,014,395
Commission and clearing fees
Revenues:
Revenue from contract with customer	$ 487.2	$ 403.6	$ 372.4
Consulting, management and account fees
Revenues:
Revenue from contract with customer	$ 91.0	$ 83.7	$ 79.6