Associate (Employee) Benefit Plans - Additional Information (Detail)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Postemployment Benefits [Abstract]
Postretirement benefit plans eligibility term	Only those Associates who have achieved ten years of service
Net periodic benefit cost, discount rate	A change in the future rates of participation from 50% to 15%
Decrease in discount rate		1.00%
Decreased discount rate percentage		4.00%
Amortization of unrecognized gains losses exceed percentage	10.00%

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

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

Disclosure of how the assumed discount rate was determined and the specific source data used to support the discount rate.

+ References

No definition available.

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- Definition

A description of the events that resulted in the settlement or curtailment of the employer's defined benefit 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 (r)

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

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- Definition

Defined Benefit Plan Amortization Of Unrecognized Gains Losses Exceed Percentage

+ References

No definition available.

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- Definition

Defined benefit plan basis points decrease in discount rate.

+ References

No definition available.

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