Weighted-Average Assumptions Used to Determine Benefit Obligations (Detail)	Dec. 31, 2015	Dec. 31, 2014
Pension Plans [Member]
Schedule Of Benefit Obligations Weighted Average Assumptions [Line Items]
Discount rate	4.04%	3.78%
Rate of compensation increase	3.74%	3.76%
Other Retirement Plans [Member]
Schedule Of Benefit Obligations Weighted Average Assumptions [Line Items]
Discount rate	4.00%	3.65%

Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]

No definition available.

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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=35743120&loc=d3e1928-114920

+ Details

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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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