Postretirement Plans - Summary of Components of Net Periodic Benefit Costs and Other Amounts Recognized in Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 22.7	$ 19.3
Interest cost	56.1	56.5
U.S. Postretirement Health Care Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.1	$ 0.1
Interest cost	2.1	2.2	2.2
Expected return on plan assets	(0.8)	(0.9)	(1.0)
Amortization of unrecognized (gain) loss	(0.3)	(0.1)	0.3
Net periodic benefit cost	1.0	1.3	1.6
Net (gain) loss	$ 0.6	$ (0.3)	$ (2.1)

Defined benefit plan, amortization of unrecognized gains (losses)

No definition available.

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- Definition

Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

+ References

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

+ References

+ Details

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

+ Details

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

+ Details

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- Details

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