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Financial Guarantees and Warranties (Details)	12 Months Ended
	Mar. 31, 2018 USD ($)
Guarantor Obligations [Line Items]
Guarantee obligations, expiring in 2019	$ 178,000,000
Guarantee obligations, expiring in 2020	18,000,000
Guarantee obligations, expiring in 2021	7,000,000
Guarantee obligations, expiring in 2022	10,000,000
Guarantee obligations, expiring in 2023	18,000,000
Guarantee obligations, expiring after 2023	107,000,000
Guarantee Obligations Inventory Repurchase Guarantees
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 234,000,000
Guarantee Obligations Inventory Repurchase Guarantees | Minimum
Guarantor Obligations [Line Items]
Debt guarantee period	1 year
Guarantee Obligations Inventory Repurchase Guarantees | Maximum
Guarantor Obligations [Line Items]
Debt guarantee period	2 years
Guarantee Obligations Customers Debt
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 104,000,000
Guarantee Obligations Customers Debt | Minimum
Guarantor Obligations [Line Items]
Debt guarantee period	1 year
Guarantee Obligations Customers Debt | Maximum
Guarantor Obligations [Line Items]
Debt guarantee period	12 years
Standby Letters of Credit
Guarantor Obligations [Line Items]
Letters of credit outstanding	$ 259,000,000

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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