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INCOME TAXES (Tax Reform Act) (Details) - USD ($) $ in Millions | 2 Months Ended | 3 Months Ended | 7 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Feb. 28, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Impact of Tax Reform Act |  |  |  |  |  |  |
Statutory federal rate (as a percent) | 32.74% |  |  | 21.00% | 21.00% |  | 35.00%
Provisional reduction of deferred tax liabilities due to Tax Reform Act |  | $ 0.8 |  |  | $ 3.5 |  | $ 24.5
State tax, low end of range of rate (as a percent) |  |  |  |  | 6.00% |  |
State tax, high end of range of rate (as a percent) |  |  |  |  | 6.50% |  |
Effective tax rate (as a percent) |  | 24.50% | 38.60% |  | 18.40% | 34.90% |
Provisional reduction in current income tax expense due Tax Reform Act reflecting use of fiscal year rather than calendar year federal income tax filing |  |  |  |  |  |  | 1.3
Alternative fuel tax credit |  |  |  |  |  |  | $ 1.2

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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to the alternative fuel tax credit. + References No definition available. + Details
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