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EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans | Sep. 30, 2018 | Sep. 30, 2017
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EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans [Line Items] |  |
Defined benefit plan, total actual weighted average plan asset allocations | 100.00% | 100.00%
Target Plan Asset Allocations | 100.00% |
Cash and equivalents [Member] |  |
EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans [Line Items] |  |
Defined benefit plan, total actual weighted average plan asset allocations | 18.00% | 18.00%
Target Plan Asset Allocations | 0.00% |
Equity securities [Member] |  |
EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans [Line Items] |  |
Defined benefit plan, total actual weighted average plan asset allocations | 68.50% | 58.00%
Target Plan Asset Allocations | 63.00% |
Fixed income [Member] |  |
EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans [Line Items] |  |
Defined benefit plan, total actual weighted average plan asset allocations | 9.50% | 19.30%
Target Plan Asset Allocations | 37.00% |
Other [Member] |  |
EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans [Line Items] |  |
Defined benefit plan, total actual weighted average plan asset allocations | 4.00% | 4.70%
Target Plan Asset Allocations | 0.00% |

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + 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=112275985&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: 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=108410482&loc=d3e1928-114920 + Details
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