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EMPLOYEE BENEFIT PLANS - Plan Assets and Investment Policy (Details) | 12 Months Ended
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Jun. 30, 2019 | Jun. 30, 2018
Plan Assets and Investment Policy |  |
Expected Rate of Return (as a percent) | 4.40% | 4.70%
Combined |  |
Plan Assets and Investment Policy |  |
Proportion of Fair Value (as a percent) | 100.00% | 100.00%
Expected Rate of Return (as a percent) | 4.40% | 4.70%
Equity securities |  |
Plan Assets and Investment Policy |  |
Proportion of Fair Value (as a percent) | 82.00% | 83.00%
Expected Rate of Return (as a percent) | 5.00% | 6.00%
Debt securities |  |
Plan Assets and Investment Policy |  |
Proportion of Fair Value (as a percent) | 17.00% | 17.00%
Expected Rate of Return (as a percent) | 1.00% | 1.00%
Cash |  |
Plan Assets and Investment Policy |  |
Proportion of Fair Value (as a percent) | 1.00% |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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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. + References No definition available. + Details
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- Definition Percentage of investment to total investment within defined benefit plan asset category. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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