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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, DEFINED BENEFIT (Details) (USD $) | 12 Months Ended
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Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2012
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of noncontributory medical and life insurance plans | 2 |  |
Pension Plans Excluding Pension Equalization Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 0 | $ 20,000,000 | $ 20,000,000
OPEB [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 4,970,000 | $ 5,977,000 | $ 5,800,000

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- Definition Defined Benefit Plan, Number of Insurance Plans + References No definition available. + Details
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- Definition The increase in the fair value of plan assets from contributions made by the employer. + 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 (b)(3) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Details
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