Segment Data - Financial Information for Company's Segments (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	$ 985	$ 1,176	$ 1,173
Acquisitions and other restructurings	309	480	740
Total Assets	54,012	51,765	53,904
Total Capital Expenditures	810	957	895
Total Depreciation and Amortization	2,154	2,253	1,978
Operating Segments
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	4,403	4,976	4,137
Total Assets	49,339	49,217	50,938
Operating Segments | Medical
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	2,274	2,824	2,624
Total Assets	23,007	22,925	23,493
Total Capital Expenditures	477	577	560
Total Depreciation and Amortization	1,104	1,073	1,028
Operating Segments | Life Sciences
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	1,405	1,248	1,207
Total Assets	4,713	4,135	4,225
Total Capital Expenditures	192	230	255
Total Depreciation and Amortization	286	284	275
Operating Segments | Interventional
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	724	903	306
Total Assets	21,619	22,157	23,219
Total Capital Expenditures	119	120	65
Total Depreciation and Amortization	750	881	658
Segment Reconciling Items
Segment Reporting Information [Line Items]
Acquisitions and other restructurings	309	480	740
Net interest expense	(521)	(627)	(641)
Corporate and All Other
Segment Reporting Information [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	(2,587)	(2,693)	(1,583)
Total Assets	4,673	2,548	2,966
Total Capital Expenditures	22	30	14
Total Depreciation and Amortization	$ 14	$ 14	$ 17