Pension And Postretirement Benefits (Schedule of Estimated Future Benefit Payments) (Details) $ in Millions	Jul. 31, 2016 USD ($)
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	$ 176
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	164
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	168
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	161
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	161
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	808
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	28
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	28
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	27
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	26
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	24
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	$ 99

No definition available.

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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