Accounts Receivable Factoring and Securitization (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 EUR (€)	Sep. 30, 2019 USD ($)
Accounts Receivable Factoring And Securitization [Line Items]
On-balance sheet arrangement, Total Facility Size						$ 115,000,000
On-balance sheet arrangement, Utilized						108,000,000		$ 13,000,000
Off-balance sheet arrangement, Total Facility Size					€ 210,000,000	307,000,000
Off-balance sheet arrangement, Utilized					177,000,000	244,000,000	€ 154,000,000	226,000,000
Costs associated with off balance sheet factoring arrangements	$ 1,000,000	$ 2,000,000	$ 2,000,000	$ 3,000,000
Committed U.S. accounts receivable securitization
Accounts Receivable Factoring And Securitization [Line Items]
On-balance sheet arrangement, Total Facility Size						115,000,000
On-balance sheet arrangement, Utilized						108,000,000		13,000,000
Committed U.S. accounts receivable securitization | Letter of Credit
Accounts Receivable Factoring And Securitization [Line Items]
Letters of credit outstanding						4,000,000		4,000,000
Committed Swedish factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size					155,000,000	171,000,000
Off-balance sheet arrangement, Utilized					133,000,000	147,000,000	109,000,000	119,000,000
Liquidity commitment			364 days
Committed U.S. factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size						75,000,000
Off-balance sheet arrangement, Utilized						48,000,000		58,000,000
Uncommitted U.K. factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size					25,000,000	28,000,000
Off-balance sheet arrangement, Utilized					5,000,000	5,000,000	6,000,000	6,000,000
Uncommitted Italy factoring facility
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Total Facility Size					30,000,000	33,000,000
Off-balance sheet arrangement, Utilized					22,000,000	25,000,000	21,000,000	23,000,000
Other uncommitted factoring facilities
Accounts Receivable Factoring And Securitization [Line Items]
Off-balance sheet arrangement, Utilized					€ 17,000,000	$ 19,000,000	€ 18,000,000	$ 20,000,000