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EMPLOYEE BENEFIT PLANS - MIX AND TARGETED ALLOCATION (Details) | Sep. 30, 2017 | Sep. 30, 2016
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Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 100.00% |
Assets | 100.00% | 100.00%
U.S. equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 40.00% |
Assets | 39.00% | 38.00%
International equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 20.00% |
Assets | 21.00% | 20.00%
Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 40.00% |
Assets | 40.00% | 42.00%

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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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