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Share-Based Payment Arrangement, Noncurrent Liabilities, Other

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Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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STOCK-BASED COMPENSATION - Narratives (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2024	Oct. 03, 2019	Oct. 02, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense	$ 146	$ 152	$ 188
Stock option weighted-average grant date fair value (in USD per share)	$ 519.89	$ 549.03	$ 397.31
Unrecognized compensation cost related to non-vested awards expected to vest	$ 265
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 9 months 18 days
Fair value of options vested	$ 136	$ 107	$ 97
Dividend equivalent payments, current (Note 16)	54	59
Dividend Equivalent Payments on Certain Stock Options, Non-current	52
Share-Based Payment Arrangement, Tax Benefit	28	24	24
Share-Based Payment Arrangement, Noncurrent Liabilities, Other	67	102
Dividend Equivalent Payments	59	208	233
Proceeds from exercise of stock options	155	166	245
Income Statement Location [Axis]: us-gaap:CostOfGoodsAndServicesSold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense	15	15	18
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense	131	137	170
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Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense	(24)
Location, Statement of Financial Position, Activity, Capitalization [Axis]: us-gaap:OtherLiabilitiesNoncurrent
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense		2	54
Additional Paid-In Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock and deferred compensation expense	$ 170	150	134
2019 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock				4,000,000
Remaining shares available for grant (in shares)	2,708,865
2014 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock					5,000,000
2003 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised	$ 516	$ 600	$ 794