Pension Benefits - Schedule of Plan Assets Allocations (Detail) (Pension Benefits [Member])	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Equity Securities, Target Allocation, Minimum	55.00%
Equity Securities, Target Allocation, Maximum	65.00%
Debt Securities, Target Allocation, Minimum	27.00%
Debt Securities, Target Allocation, Maximum	33.00%
Real Estate, Target Allocation, Minimum	8.00%
Real Estate, Target Allocation, Maximum	12.00%
Plan Assets, Total	100.00%	100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan Assets, Debt Securities	60.00%	60.00%	61.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan Assets, Debt Securities	30.00%	31.00%	32.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan Assets, Debt Securities	10.00%	9.00%	7.00%

Defined Benefit Plan Target Allocation Percentage 1

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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

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

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