PENSION AND OTHER POSTRETIREMENT BENEFITS Assumptions used in calculations (Details)	12 Months Ended
Jul. 31, 2018	Jul. 31, 2017
Pension Benefits
Defined Benefit Plans and Postretirement Health Benefits
Discount rate for net periodic benefit costs	3.75%	3.36%
Discount rate for year-end obligations	4.04%	3.75%
Rate of increase in compensation levels for net periodic benefit costs	3.50%	3.50%
Rate of increase in compensation levels for year-end obligations	3.50%	3.50%
Long-term expected rate of return on assets	7.00%	7.00%
Postretirement Health Benefits
Defined Benefit Plans and Postretirement Health Benefits
Discount rate for net periodic benefit costs	3.26%	2.71%
Discount rate for year-end obligations	3.81%	3.26%
Rate of increase in compensation levels for net periodic benefit costs	0.00%	0.00%
Rate of increase in compensation levels for year-end obligations	0.00%	0.00%
Long-term expected rate of return on assets	0.00%	0.00%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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

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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/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=82843861&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

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No definition available.

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