Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Restructuring (Details) - USD ($) $ in Millions	3 Months Ended								5 Months Ended	12 Months Ended
Restructuring (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2017	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Restructuring Costs [Abstract]
Restructuring costs	$ 13	$ 0	$ 2	$ 2	$ 7	$ 1	$ 2	$ 0	$ 14	$ 17	$ 10	$ 14
Acquired deferred costs											7
Payments for restructuring											$ 3