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EMPLOYEE BENEFIT PLANS (Details) - Weighted-average assumptions used in determining the net periodic benefit costs | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Pension Plan [Member] |  |  |
EMPLOYEE BENEFIT PLANS (Details) - Weighted-average assumptions used in determining the net periodic benefit costs [Line Items] |  |  |
Discount rate | 2.92% | 4.10% | 3.64%
Expected return on assets | 7.00% | 7.00% | 7.25%
Supplemental Employee Retirement Plan [Member] |  |  |
EMPLOYEE BENEFIT PLANS (Details) - Weighted-average assumptions used in determining the net periodic benefit costs [Line Items] |  |  |
Discount rate | 2.64% | 3.99% | 3.18%
Expected return on assets | 0.00% | 0.00% | 0.00%

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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 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)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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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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