Pension Plans - Summary of Amounts in Accumulated OCI to be Amortized Over Next Fiscal Year (Detail) $ in Millions	12 Months Ended
Dec. 30, 2017 USD ($)
Retirement Benefits [Abstract]
Amortization of unrecognized loss	$ 32.0
Amortization of prior service credit	(1.2)
Total to be recognized in net periodic benefit cost	$ 30.8

Defined Benefit Plan Future Amortization Of Unrecognized Gain Loss

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- References

No definition available.

+ Details

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- Definition

Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

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