Postretirement Benefit Plans (Details Textual) (USD $) In Millions, unless otherwise specified	6 Months Ended
Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]
Expected long-term rate of return on plan assets	6.10%
Defined Benefit Plan, Plan Amendments	$ 11
Maximum amortization period of unfunded actuarial liability	15 years 0 months
Expected additional contribution to funded pension plan	22
Expected additional contribution to unfunded pension plan	10
Expected additional contribution to savings and defined contribution plans	$ 11

Additional contributions to funded pension plan.

No definition available.

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- Definition

Additional contributions to savings and defined contribution plans.

+ References

No definition available.

+ Details

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- Definition

Additional contributions to unfunded pension plan.

+ References

No definition available.

+ Details

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- Definition

Maximum amortization period of unfunded actuarial liability.

+ References

No definition available.

+ Details

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- Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520743

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520782

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(7)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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