Financial Guarantees and Warranties (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2015
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	$ 1
Guarantee obligations, expiring in 2016	137
Guarantee obligations, expiring in 2017	42
Guarantee obligations, expiring in 2018	16
Guarantee obligations, expiring in 2019	21
Guarantee obligations, expiring in 2020	25
Guarantee obligations, expiring after 2020	127
Guarantee Obligations Inventory Repurchase Guarantees [Member]
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	185
Guarantee Obligations Inventory Repurchase Guarantees [Member] \| Minimum [Member]
Guarantor Obligations [Line Items]
Number of years for which agreements or guarantees extend	1
Guarantee Obligations Inventory Repurchase Guarantees [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Number of years for which agreements or guarantees extend	2
Guarantee Obligations Customers Debt [Member]
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	183
Guarantee Obligations Customers Debt [Member] \| Minimum [Member]
Guarantor Obligations [Line Items]
Number of years for which agreements or guarantees extend	1
Guarantee Obligations Customers Debt [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Number of years for which agreements or guarantees extend	15
Standby Letters of Credit [Member]
Guarantor Obligations [Line Items]
Letters of credit outstanding	142
Commitment to investee building and equipment construction [Member]
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 16

Guarantee Obligations Exposure Expiring in Year Five

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- Definition

Guarantee Obligations Exposure Expiring in Year Five Thereafter

+ References

No definition available.

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- Definition

Guarantee Obligations Exposure Expiring in Year Four

+ References

No definition available.

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- Definition

Guarantee Obligations Exposure Expiring in Year One

+ References

No definition available.

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- Definition

Guarantee Obligations Exposure Expiring in Year Three

+ References

No definition available.

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- Definition

Guarantee Obligations Exposure Expiring in Year Two

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ 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 (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

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=6851643&loc=d3e12069-110248

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- Definition

Describe the approximate term of the guarantee or each group of similar guarantees.

+ 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 (a)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

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

+ References

No definition available.

+ Details

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