Summary of Weighted Average Assumptions Used in Determining Pension Costs (Detail)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. Benefit Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	4.20%	5.10%
Rate of increase in compensation levels	3.50%	3.50%
U.S. Benefit Plans \| Pension Plans, Defined Benefit
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	5.10%	4.20%	5.00%
Rate of increase in compensation levels	3.50%	3.50%	3.50%
Expected long term rate of return on plan assets	7.60%	7.90%	8.10%
Non-U.S. Benefit Plan
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	3.50%	4.50%
Non-U.S. Benefit Plan \| Pension Plans, Defined Benefit
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	4.50%	4.10%	4.60%
Rate of increase in compensation levels	0.00%	0.00%	0.00%
Expected long term rate of return on plan assets	5.90%	5.10%	5.30%

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

+ 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 (k)(1)

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

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)

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

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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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