Plan Assumptions (Detail)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
For measuring benefit obligations at year end
Discount rate	4.72%	3.83%	4.27%
Rate of compensation increase	4.00%	4.00%	5.00%
Expected return on plan assets	7.50%	8.00%	8.25%
For measuring net periodic benefit cost
Discount rate	3.83%	4.27%	5.39%
Rate of compensation increase	4.00%	5.00%	5.00%
Expected return on plan assets	7.50%	8.00%	8.25%

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Expected Long Term Return on Assets

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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

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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=28361610&loc=d3e1928-114920

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

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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

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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