Pension Benefits Pension Benefits (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Net periodic pension expense	$ 11	$ 11
Defined Benefit Plan, Contributions by Employer	$ 15	$ 5
Defined Benefit Plan, Actuarial Losses, Percentage Exceeding Greater Of Projected Benefit Obligation Or Market Value of Assets	10.00%

Defined Benefit Plan, Straight-line Amortization of Unrecognized Actuarial Losses, when Percentage Exceeds Greater Of Projected Benefit Obligation Or Market Value of Assets

No definition available.

+ Details

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Period Type:	instant

- Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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