Schedule of Weighted Average - Assumptions to Determine Net Periodic Pension Cost (Detail)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Postretirement Benefit Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	4.10%	3.10%	3.70%
Initial Health Care Cost Trend Rate	8.00%	8.50%	9.00%
Ultimate Health Care Cost Trend Rate	5.00%	5.00%	5.00%
Year in which Ultimate Health Care Cost Trend Rate is reached	2020	2020	2020
United States \| Defined Benefit Pension Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	4.50%	3.60%	4.20%
Expected return on plan assets	5.00%	5.00%	5.00%
Salary progression rate	3.00%	3.00%	3.00%
Foreign \| Defined Benefit Pension Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	3.80%	3.70%	4.90%
Expected return on plan assets	3.40%	3.70%	3.10%
Salary progression rate	3.50%	3.50%	3.40%

Defined benefit plan assumptions used calculating net periodic benefit cost salary progression rate.

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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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 assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ 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 (l)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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- Definition

The ultimate trend rate for health care costs.

+ References

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

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