Consolidated Income Statements - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Revenues:
Total revenues	$ 60,856.1	$ 66,036.0	$ 42,534.2
Cost of sales of physical commodities	57,942.0	63,928.6	40,861.1
Operating revenues	2,914.1	2,107.4	1,673.1
Transaction-based clearing expenses	271.8	291.2	271.7
Introducing broker commissions	161.6	160.1	160.5
Interest expense	802.2	135.5	49.6
Interest expense on corporate funding	57.5	44.7	41.3
Net operating revenues	1,621.0	1,475.9	1,150.0
Compensation and other expenses:
Compensation and benefits	868.6	794.8	679.1
Trading systems and market information	74.0	66.2	58.8
Professional fees	57.0	54.3	40.9
Non-trading technology and support	61.6	52.4	46.0
Occupancy and equipment rental	40.4	36.1	34.2
Selling and marketing	54.0	55.3	33.3
Travel and business development	24.8	16.9	4.5
Communications	9.1	8.3	9.3
Depreciation and amortization	51.0	44.4	36.5
Bad debts, net of recoveries	16.5	15.8	10.4
Other	66.4	60.6	46.3
Total compensation and other expenses	1,323.4	1,205.1	999.3
Gain on acquisitions and other gains, net	25.4	6.4	3.4
Income from operations, before tax	323.0	277.2	154.1
Income tax expense	84.5	70.1	37.8
Net income	$ 238.5	$ 207.1	$ 116.3
Earnings per share:
Basic (in dollar per share)	$ 11.55	$ 10.27	$ 5.90
Diluted (in dollar per share)	$ 11.18	$ 10.01	$ 5.74
Weighted-average number of common shares outstanding:
Basic (in shares)	19,957,333	19,570,403	19,130,643
Diluted (in shares)	20,619,340	20,067,540	19,678,168
Sales of physical commodities
Revenues:
Total revenues	$ 58,131.2	$ 64,052.6	$ 40,961.6
Principal gains, net
Revenues:
Total revenues	1,079.9	1,145.2	892.0
Commission and clearing fees
Revenues:
Total revenues	498.4	507.9	487.2
Consulting, management, and account fees
Revenues:
Total revenues	159.0	111.3	91.0
Interest income
Revenues:
Total revenues	$ 987.6	$ 219.0	$ 102.4