Share-Based Compensation - Compensation Cost Relating to Share-Based Payments (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost relating to share-based payments	$ 261	$ 240	$ 238
Income tax benefit recognized	58	55	55
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost relating to share-based payments	50	46	43
Selling and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost relating to share-based payments	170	156	158
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost relating to share-based payments	41	37	36
Acquisition-related integration and restructuring expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost relating to share-based payments	$ 0	$ 1	$ 1