Postretirement Benefit Plans (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Contributions to employee benefit plans
Funded pension plans	$ 8	$ 4	$ 12	$ 10
Unfunded pension plans	3	3	4	5
Savings and defined contribution pension plans	5	4	11	9
Total contributions	$ 16	$ 11	$ 27	$ 24

Defined contribution plan employers contribution to funded pension plan.

No definition available.

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- Definition

Defined contribution plan employer's contribution to unfunded pension plan.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund its pension plans and its non-pension postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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