Related Party Transactions and Parent Company Investment - Transfer (To) From Parent (Details) - USD ($) $ in Millions	2 Months Ended	5 Months Ended	12 Months Ended
May 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Oct. 31, 2016
Related Party Transactions [Abstract]
Cash pooling and general financing activities	$ (176)	$ (1)	$ (506)	$ (512)
Corporate allocations	24	58	158	152
Income taxes	7	(15)	19	63
Transfers (to) from Parent, net	$ (145)	$ 42	$ (329)	$ (297)

Related Party Transaction, Income Taxes From Transactions With Related Party

No definition available.

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- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

+ Details

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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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