Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates (Detail) (Foreign Postretirement Benefit Plan [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Foreign Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Effect on total of service and interest cost components one percentage point increase	$ 1
Effect on OPEB obligations one percentage point increase	14
Effect on total of service and interest cost components one percentage point decrease	(1)
Effect on OPEB obligations one percentage point decrease	$ (12)

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)

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

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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