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INCOME TAXES - Tax Cuts and Jobs Act of 2017 (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Dec. 31, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
INCOME TAXES |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 24.50% | 35.00% | 35.00%
Income tax expense (benefit) related to new tax act | $ 502.1 | $ 502.1 |  |

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- Definition Amount of reasonable estimate for income tax expense (benefit) from effect of Tax Cuts and Jobs Act of 2017 for which accounting for tax effect is incomplete. + References No definition available. + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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