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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

Target allocation 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=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)(i)

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

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- Definition

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=35743120&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

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Postretirement Plans - Summary of Target Allocation and Weighted-Average Asset Allocation by Asset Category and Fair Value of Plan Assets (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,103.4	$ 1,015.4	$ 964.0
Voluntary Employees Beneficiary Association Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
Actual weighted-average asset allocation	100.00%	100.00%
Fair value of plan assets	14.7	15.0
Voluntary Employees Beneficiary Association Plan Assets [Member] \| Debt securities and cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	46.00%
Actual weighted-average asset allocation	45.00%	13.00%
Voluntary Employees Beneficiary Association Plan Assets [Member] \| Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	29.00%
Actual weighted-average asset allocation	29.00%	57.00%
Fair value of plan assets	4.2	8.6
Voluntary Employees Beneficiary Association Plan Assets [Member] \| Hedge funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	25.00%
Actual weighted-average asset allocation	26.00%	24.00%
Fair value of plan assets	$ 3.9	$ 3.6
Voluntary Employees Beneficiary Association Plan Assets [Member] \| Real estate and other real assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual weighted-average asset allocation		6.00%