Restructuring Charges- Activity in Restructuring Reserve (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	36 Months Ended	9 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2014
Severance
Restructuring Reserve [Roll Forward]
Net additional charges (net recovery/gain)	$ (4)
Operational Efficiency Initiatives 2011
Restructuring Reserve [Roll Forward]
Beginning Balance	28		107
Net additional charges (net recovery/gain)	(2)	(6)	36
Utilization	(4)		(115)
Ending balance	22	28	28	28
Operational Efficiency Initiatives 2011 \| Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	28		78
Net additional charges (net recovery/gain)	(2)		93
Utilization	(4)		(143)
Ending balance	22	28	28	28
Operational Efficiency Initiatives 2011 \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance	0		29
Net additional charges (net recovery/gain)	0		(57)
Utilization	0		28
Ending balance	0	0	0	0
Streamlining Actions
Restructuring Reserve [Roll Forward]
Beginning Balance	92			125
Net additional charges	(2)			59
Net additional charges (net recovery/gain)	(2)	6
Utilization	(25)			(92)
Ending balance	$ 65	$ 92	$ 92	$ 92

Amount charged against earnings in the period for incurred and estimated costs, excluding asset retirement obligations, associated with exit from or disposal of business activities or restructurings pursuant to a program that is planned and controlled by management, and materially changes either the scope of a business undertaken by an entity, or the manner in which that business is conducted. Also includes credit adjustments of prior amounts charged against earnings.

No definition available.

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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-Publisher FASB

-Name Accounting Standards Codification

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

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