Debt and Other Financing Activities - U.S. Accounts Receivable Sales Program - Additional Information (Details) - U.S. Accounts Receivable Sales Program [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2022	Sep. 30, 2021
Disclosure Of Sales Program Of Receivable [Line Items]
Maximum limit of receivables can transfer		$ 125	$ 125
Sales against the buyers limit		97	113
Amount transferred in receivables		122	167
Gross cash proceeds received for receivables transferred and derecognized		177
Cash proceeds collected		193
Payments for (proceeds from) new transfers of receivables		16
Maximum [Member]
Disclosure Of Sales Program Of Receivable [Line Items]
Gain (loss) on sale of receivables	$ (1)	(1)
Recorded liabilities related to service obligations and limited guarantee	$ 1	$ 1	$ 1