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Schedule of Weighted Average Assumptions to Determine Pension Obligations (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
United States Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Discount rate	4.00%	3.70%
Salary progression rate	2.70%	2.90%
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Discount rate	2.30%	2.60%
Salary progression rate	3.20%	3.20%
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Discount rate	3.90%	3.50%	4.10%
Initial medical trend	7.50%	7.50%	8.00%
Ultimate health care trend	5.00%	5.00%	5.00%
Medical cost trend rate decrease to ultimate rate in year	2023	2022	2020

X

- Definition

Defined benefit plan assumptions used calculating benefit obligation initial medical trend.

+ References

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- Definition

Defined benefit plan assumptions used calculating benefit obligation medical cost trend rate decrease to ultimate rate in year.

+ References

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- Definition

Defined benefit plan assumptions used calculating benefit obligation salary progression rate.

+ References

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- Definition

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=58740216&loc=d3e1928-114920

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- Definition

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- Definition

The ultimate trend rate for health care costs.

+ 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=58740216&loc=d3e1928-114920

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