Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Net sales and other operating revenues	$ 3,713	$ 3,994	$ 3,931
Cost of sales	2,773	3,034	3,092
Gross profit	940	960	839
Selling and administrative expenses	260	283	253
Research and technical expenses	59	63	57
Loss on sale of business			3
Income (loss) from operations	621	614	526
Interest and dividend income	27	32	31
Interest expense	(76)	(81)	(90)
Other income (expense)	(7)	(36)	(16)
Income (loss) from operations before income taxes and equity in earnings of affiliated companies	565	529	451
(Provision) benefit for income taxes	(196)	(111)	28
Equity in earnings of affiliated companies, net of tax	7	6	5
Net income (loss)	376	424	484
Net income (loss) attributable to noncontrolling interests, net of tax of $12, $11 and $9	45	44	39
Net income (loss) attributable to Cabot Corporation	$ 331	$ 380	$ 445
Weighted-average common shares outstanding:
Basic	53.7	55.1	56.1
Diluted	54.2	55.7	56.5
Earnings (loss) per common share:
Basic	$ 6.07	$ 6.79	$ 7.79
Diluted	$ 6.02	$ 6.72	$ 7.73

Earning per share basic and diluted.

No definition available.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.