Weighted Average Assumptions Used for Pension Plans (Detail)	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Pension plans
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Weighted average assumptions used to determine benefit obligations, Discount rate	2.78%	2.54%	3.41%
Weighted average assumptions used to determine benefit obligations, Rate of compensation increase	3.00%	3.00%	3.00%
Weighted average assumptions used to determine Measurement date	Jan. 01, 2020	Jan. 01, 2019	Jan. 01, 2018
Weighted average assumptions used to determine net periodic benefit cost/(income), Discount rate	2.54%	3.41%	3.58%
Weighted average assumptions used to determine net periodic benefit cost/(income), Expected return on plan assets	4.97%	5.34%	5.34%
Weighted average assumptions used to determine net periodic benefit cost/(income), Rate of compensation increase	3.00%	3.00%	3.00%
Postretirement Benefit Plans \| Benefit Obligations
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Weighted average assumptions used to determine benefit obligations, Discount rate	2.11%	3.01%	4.07%
Health care cost trend rate, Initial rate	6.50%	6.50%	6.50%
Health care cost trend rate, Ultimate rate	5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate	2027	2026	2025
Postretirement Benefit Plans \| Net Periodic Benefit Cost
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date	Jan. 01, 2020	Jan. 01, 2019	Jan. 01, 2018
Weighted average assumptions used to determine net periodic benefit cost/(income), Discount rate	3.01%	4.07%	3.36%
Health care cost trend rate, Initial rate	6.50%	6.50%	6.00%
Health care cost trend rate, Ultimate rate	5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate	2026	2025	2022

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

No definition available.

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- Definition

Month-end measurement date applicable when an accounting policy election is made to measure plan assets and benefit obligations as of the month-end that is closest to the fiscal year-end, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

+ Details

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Details

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- Details

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- Details

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