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INCOME TAXES - IMPACT OF TAX ACT (Details) $ in Thousands | 12 Months Ended
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Sep. 30, 2018 USD ($)
Income Tax Contingency [Line Items] |
Income tax (benefit) provision | $ (59,627)
Clean Energy Ventures |
Income Tax Contingency [Line Items] |
Income tax (benefit) provision | (61,423)
Energy Services |
Income Tax Contingency [Line Items] |
Income tax (benefit) provision | 6,062
Midstream |
Income Tax Contingency [Line Items] |
Income tax (benefit) provision | (13,946)
Home Services and Other |
Income Tax Contingency [Line Items] |
Income tax (benefit) provision | $ 9,680

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