Postretirement Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Jan. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Prior unrecognized losses included in Accumulated OCI	0.3
Voluntary Employees Beneficiary Association Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Description of basis used to determine overall expected long-term, rate-of-return-on-assets assumption	The objective of the VEBA trust is to achieve net of expense returns that meet or exceed the 6.8% long-term, rate-of-return-on-assets assumption used for reporting purposes
U.S. Postretirement Health Care Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate, 2015	7.20%
Health care cost trend rate, 2028	4.50%
Increase in accumulated postretirement benefit obligation	0.9
Increase in service cost and interest cost components	0.1
Decrease in accumulated postretirement benefit obligation	0.8
Decrease in service cost and interest cost components	0.1

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

Reference 1: 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=36458714&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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-Section 45

-Paragraph 14

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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.

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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.

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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.

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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.

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The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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A narrative description of the basis used to determine the overall expected long-term rate-of-return on assets assumption, such as the general approach used, the extent to which the overall rate-of-return on assets assumption was based on historical returns, the extent to which adjustments were made to those historical returns to reflect expectations of future returns, and how those adjustments were determined. The description would generally consider the major categories of assets.

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The ultimate trend rate for health care costs.

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