Summary of Effect of One Percent Point Change in Assumed Health Care Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013
Compensation And Retirement Disclosure [Abstract]
One-Percentage Point Decrease, Effect on total of service and interest cost	$ (65)	$ (60)	$ (64)
One-Percentage Point Decrease, Effect on postretirement benefit obligation	(554)	(558)	(485)
One-Percentage Point Increase, Effect on total of service and interest cost	76	68	73
One-Percentage Point Increase, Effect on postretirement benefit obligation	$ 626	$ 629	$ 542

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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