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INFORMATION BY OPERATING SEGMENT - Reconciliation of Consolidated Net Economic Earnings to Consolidated Net Income (Details) - USD ($) $ in Millions | 3 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Segment Reporting [Abstract] |  |
Net Income | $ 116.0 | $ 45.2
Unrealized loss on energy-related derivative contracts | 0.8 | 3.8
Lower of cost or market inventory adjustments | 0.0 | (0.1)
Realized gain on economic hedges prior to sale of the physical commodity | (0.1) | (0.1)
Acquisition, divestiture and restructuring activities | 1.7 | 0.1
Income tax effect of adjustments | (0.6) | (1.4)
Effects of the Tax Cuts and Jobs Act | (59.9) | 0.0
Net Economic Earnings | $ 57.9 | $ 47.5

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- Definition Change in earnings, net of income tax, that represents costs related to acquisition, divestiture, and restructuring activities. + References No definition available. + Details
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- Definition Charge to earnings, net of income tax, that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions. + References No definition available. + Details
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- Definition Net economic earnings exclude from reported net income the after-tax impact of net unrealized gains and losses and other timing differences associated with energy-related transactions. Net economic earnings will also exclude, if applicable, the after-tax impact of costs related to acquisition, divestiture, and restructuring activities. + References No definition available. + Details
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- Definition Realized Gain (Loss) On Economic Hedges Prior To Sale Of Physical Commodity, Net Of Tax + References No definition available. + Details
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