Associate Retirement Plans - Summary of Reconciliation of Beginning and Ending Balances for Level 3 Assets (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Dec. 28, 2013	Jan. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value at end of year	$ 105,949	$ 93,718
Guaranteed annuity contract [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value at end of year	18,071	17,749
Significant unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value at end of year	18,071	17,749
Significant unobservable inputs (Level 3) [Member] \| Guaranteed annuity contract [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning of year	3,890	18,071
Balance assumed in merger	14,324
Purchases, sales, issuances and settlements, net	(578)	(1,402)
Interest income	236	799
Realized gains	199	281
Plan assets at fair value at end of year	$ 18,071	$ 17,749

Defined benefit pensions plans interest income.

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- Definition

Actual return on plan assets, separately identifying the amount related to assets sold during the period.

+ 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)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=35743120&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)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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- Definition

The amount of increase in the plan assets attributed to a business combination.

+ References

+ Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ 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 (b)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930

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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ 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)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=35743120&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)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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