Accounts Receivable Factoring and Securitization (Details) € in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 EUR (€)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 EUR (€)
Accounts Receivable Factoring And Securitization [Line Items]
On-balance sheet arrangement, Total Facility Size	$ 110		$ 110
On-balance sheet arrangement, Utilized	97		97			$ 3
Off-balance sheet arrangement, Total Facility Size	307		307		€ 210
Off-balance sheet arrangement, Utilized	250		250		155	173	€ 106
Costs associated with off balance sheet factoring arrangements	2	$ 1	3	$ 2
Committed U.S. accounts receivable securitization
Accounts Receivable Factoring And Securitization [Line Items]
On-balance sheet arrangement, Total Facility Size	110		110
On-balance sheet arrangement, Utilized	97		97			3
Committed U.S. accounts receivable securitization | Letter of Credit
Accounts Receivable Factoring And Securitization [Line Items]
Letters of credit outstanding	2		2			3
Committed Swedish factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size	171		171		155
Off-balance sheet arrangement, Utilized	128		$ 128		116	88	75
Liquidity commitment			364 days
Committed U.S. factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size	75		$ 75
Off-balance sheet arrangement, Utilized	79		79			49
Uncommitted U.K. factoring facility (4)
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size	28		28		25
Off-balance sheet arrangement, Utilized	7		7		6	2	2
Uncommitted Italy factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size	33		33		30
Off-balance sheet arrangement, Utilized	13		13		12	17	14
Other uncommitted factoring facilities
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Utilized	$ 23		$ 23		€ 21	$ 17	€ 15