Weighted Average Assumptions Used for Pension Plans (Detail)	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine net periodic cost, Expected return on plan assets	8.00%
Net Periodic Pension Cost
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine net periodic cost, Discount rate	4.75%	4.00%	4.70%
Weighted average assumptions used to determine benefit obligations, Discount rate	4.00%	4.75%	4.00%
Weighted average assumptions used to determine benefit obligations, Rate of compensation increase	4.00%	4.00%	4.00%
Weighted average assumptions used to determine net periodic cost, Expected return on plan assets	8.00%	8.00%	8.00%
Weighted average assumptions used to determine net periodic cost, Rate of compensation increase	4.00%	4.00%	4.00%
Net Periodic Pension Cost \| Benefit Obligations
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine Measurement date	12/31/2014	12/31/2013	12/31/2012
Net Periodic Pension Cost \| Net (Income) Cost
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine Measurement date	1/1/2014	1/1/2013	1/1/2012
Net Periodic Postretirement Benefit Cost \| Benefit Obligations
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine benefit obligations, Measurement date	12/31/2014	12/31/2013	12/31/2012
Weighted average assumptions used to determine benefit obligations, Discount rate	3.50%	4.31%	3.34%
Health care cost trend rate, Initial rate	8.00%	8.50%	8.00%
Health care cost trend rate, Ultimate rate	5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate	2021	2021	2019
Net Periodic Postretirement Benefit Cost \| Net Periodic Benefit Cost
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Weighted average assumptions used to determine net periodic cost, Measurement date	1/1/2014	1/1/2013	1/1/2012
Weighted average assumptions used to determine net periodic cost, Discount rate	4.31%	3.34%	4.35%
Health care cost trend rate, Initial rate	8.50%	8.00%	8.50%
Health care cost trend rate, Ultimate rate	5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate	2021	2019	2019

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Measurement Date

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- Definition

Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Measurement Date

+ References

No definition available.

+ Details

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

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

+ References

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- Definition

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

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ Details

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- Definition

The date(s) used to measure (at least the majority of) plan assets and benefit obligations for defined benefit pension and other postretirement benefit plans. Disclosure required by FAS 132R paragraph 5k prior to being amended by FAS 158.

+ References

No definition available.

+ Details

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

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