Pension Plans - Summary of Changes in Fair Value of Assets with Level 3 Inputs (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013
Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	$ 175.1	$ 163.6
Realized gains (losses) on assets sold	8.2	4.0
Unrealized gains attributable to assets held	7.7	15.6
Net purchases and settlements	(21.3)	(8.1)
Ending balance	169.7	175.1
Hedge Funds [Member] \| Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	90.3	75.0
Realized gains (losses) on assets sold	0.6	(1.5)
Unrealized gains attributable to assets held	3.4	13.4
Net purchases and settlements	(2.8)	3.4
Ending balance	91.5	90.3
Hedge Funds [Member] \| Foreign Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	24.8	20.0
Unrealized gains attributable to assets held	0.1	1.5
Net purchases and settlements	(6.8)	3.3
Ending balance	18.1	24.8
Private Equity Partnerships [Member] \| Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	49.4	49.6
Realized gains (losses) on assets sold	6.0	5.4
Unrealized gains attributable to assets held	1.1	1.6
Net purchases and settlements	(9.1)	(7.2)
Ending balance	47.4	49.4
Real Estate and Other Real Assets [Member] \| Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	35.4	39.0
Realized gains (losses) on assets sold	1.6	0.1
Unrealized gains attributable to assets held	3.2	0.6
Net purchases and settlements	(9.4)	(4.3)
Ending balance	$ 30.8	$ 35.4

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Unrealized Gains (Losses) Attributable To Assets Held

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph c

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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