PENSION AND OTHER POSTRETIREMENT BENEFITS - Assumptions Used to Determine Projected Benefits and Periodic Costs (Details)	6 Months Ended	12 Months Ended
Jan. 03, 2020	Jun. 28, 2019	Jun. 29, 2018	Jun. 30, 2017
Obligation assumptions as of:
Rate of future compensation increase	2.80%	2.76%	2.76%
Cost assumptions for fiscal periods ended:
Rate of future compensation increase	2.97%	2.76%	2.76%	2.75%
Other Benefits
Obligation assumptions as of:
Discount rate	2.97%	3.21%	3.99%
Cost assumptions for fiscal periods ended:
Discount rate to determine service cost	3.47%	4.14%	3.62%	3.52%
Discount rate to determine interest cost	2.74%	3.62%	3.04%	2.60%
Pension
Obligation assumptions as of:
Discount rate	3.14%	3.35%	4.05%
Cost assumptions for fiscal periods ended:
Discount rate to determine service cost	3.11%	3.89%	3.48%	3.80%
Discount rate to determine interest cost	2.94%	3.75%	3.28%	2.94%
Expected return on plan assets	7.68%	7.66%	7.66%	7.65%

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate, Interest Cost

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate, Service Cost

+ References

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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

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

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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