Supplemental Financial Information - Other Income (Expense), Net (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Royalty Income, Nonoperating			$ 17	$ 64	$ 51
Insurance Recoveries			0	35	0
Income (Loss) from Equity Method Investments			13	18	8
Foreign Currency Transaction Gain (Loss), Realized			(17)	(23)	(14)
Losses on debt extinguishment	$ (1)	$ (57)	(8)	(59)	(16)
Other Nonoperating Income			(3)	(2)	(3)
Other Nonoperating Income (Expense)			23	43	305
Other Nonoperating Income (Expense)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)			7	(2)	(13)
Vyaire Medical
Income (Loss) from Equity Method Investments			$ 0	$ 6	$ 288