PENSION AND OTHER POSTRETIREMENT BENEFITS Narrative (Details) - USD ($)	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans
Accumulated benefit obligation	$ 54,696,000	$ 48,358,000
Defined Benefit Plan Voluntary Contribution		11,500,000
Pension plan estimated employer contributions in next fiscal year	$ 0
Postretirement Health Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans
Health care cost trend rate assumed	7.50%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.50%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2038
401K Plan
Defined Contribution Plan Disclosure
Contribution to defined contribution plans	$ 764,000	$ 782,000

Voluntary contribution to defined benefit plan in excess of the minimum required contribution.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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

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

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-Section 50
-Paragraph 1
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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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Amount of cost for defined contribution plan.

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-Publisher FASB
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