PENSION AND OTHER POSTRETIREMENT BENEFITS Effect of one-percentage point change in assumed healthcare trend (Details) - Postretirement Health Benefits $ in Thousands	12 Months Ended
Jul. 31, 2017 USD ($)
Defined Benefit Plans and Postretirement Health Benefits
Effect of One Percentage Point Increase on total service and interest cost	$ 29
Effect of One Percentage Point Decrease on total service and interest cost	(25)
Effect of One Percentage Point Increase on accumulated postretirement benefit obligation	310
Effect of One Percentage Point Decrease on accumulated postretirement benefit obligation	$ (274)

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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