Pension And Postretirement Benefits (Schedule Of Assumed Health Care Cost Trend Rates) (Details) - Other Postretirement Benefit Plan, Defined Benefit [Member]	12 Months Ended
Jul. 28, 2019	Jul. 29, 2018
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	6.25%	6.75%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.50%	4.50%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2023	2023

No definition available.

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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

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 (l)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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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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