Income Taxes	6 Months Ended
Income Taxes	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rates for the quarters ended March 31, 2021 and March 31, 2020 were 26.3% and negative 53.2%, respectively. The effective tax rates for the six months ended March 31, 2021 and March 31, 2020 were 26.8% and 139.9%, respectively. The change in the tax rate is primarily the result of a valuation allowance initially established in the quarter ended March 31, 2020, discussed below. A valuation allowance for deferred tax assets, including net operating losses and tax credits, is recognized when it is more likely than not that some or all of the benefit from the deferred tax assets will not be realized. The Company continually assesses the realizability of its deferred tax assets, including factors such as future taxable income, reversal of existing temporary differences, and tax planning strategies. The Company considers both positive and negative evidence related to the likelihood of the realization of the deferred tax assets. As of March 31, 2020, the Company recorded a valuation allowance against certain state deferred tax assets in the amount of $56.8 million based on its conclusion, considering all available objective evidence and the Company’s history of subsidiary state tax losses, that it was more likely than not that the deferred tax assets would not be realized. The valuation allowance increased to $63.9 million as of March 31, 2021 as a result of certain state net operating loss and tax credit activity. Changes in judgment regarding future realization of these deferred tax assets may result in a reversal of all or a portion of the valuation allowance. The Company will continue to re-assess this position each quarter. On March 27, 2020, the “Coronavirus Aid, Relief and Economic Security (CARES) Act” was signed into law. The CARES Act, among other things, includes provisions relating to alternative minimum tax (AMT) credit refunds, refundable payroll tax credits, deferment of employer side social security payments, net operating loss carryback periods, and modifications to the net interest deduction limitation. The 2017 Tax Reform Act had repealed the corporate AMT and provided that the Company’s existing AMT credit carryovers were refundable over a four year period. As of September 30, 2018, the Company had $85.0 million of AMT credit carryovers. The Company received the first installment for $42.5 million of AMT credit refunds related to fiscal 2019 in January 2020 and filed for the acceleration of the remaining AMT credit refunds of $42.5 million, which were received in June 2020. On December 27, 2020, the “Consolidated Appropriations Act, 2021 (CAA)” was signed into law. The CAA clarifies and expands the Paycheck Protection Program loans and the Employee Retention Credit as well as several other tax provisions first outlined in the CARES Act. The CAA is currently being evaluated, however, the Company does not anticipate a material impact as a result of this legislation. On March 11, 2021, the “American Rescue Plan Act of 2021” was signed into law. The Company is still evaluating the impacts of this legislation but does not anticipate a material impact as a result of this legislation.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.