Actuarial Assumptions Used in Calculation of Net Periodic Postretirement Benefit Cost (Detail)	12 Months Ended
Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Postemployment Benefits [Abstract]
Discount rate	3.80%	4.60%	5.70%
Rate of compensation increase	4.00%	4.00%	4.00%

Expected rate of compensation increases (for pay-related plans).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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Period Type:	duration