Income Taxes	6 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income Tax Provision The Company's income tax provision for quarterly interim periods is based on an estimated annual effective income tax rate calculated separately from the effect of significant, infrequent, or unusual items. The total income tax provision, including discontinued operations, was a tax benefit of $38.2 million and $42.1 million for the three and six months ended March 31, 2019, respectively, compared to an income tax expense of $1.0 million and $109.0 million for the three and six months ended March 31, 2018, respectively. The current fiscal year income tax benefit was primarily driven by (1) the loss from continuing operations due to the $148.6 million of impairments on our land inventory assets and (2) the completion of work necessary to claim an additional $5.4 million in tax credits related to prior fiscal years, partially offset by discrete impacts related to stock-based compensation. The tax expense for the six months ended March 31, 2018 was primarily driven by the remeasurement of the Company's deferred tax assets as a result of the enactment of the Tax Cuts and Jobs Act and several discrete tax items, including stock-based compensation. These items were partially offset by the loss incurred from continuing operations and completion of the work necessary to claim an additional $2.3 million in tax credits related to prior fiscal years. Deferred Tax Assets and Liabilities As of March 31, 2019, the net deferred tax asset is comprised of various tax attributes that include $9.6 million of minimum tax credit carryforwards. Beginning with the fiscal 2019 tax return, the Company will be able to make cash refund claims for significant portions of these credits due to the elimination of the alternative minimum tax in the Tax Cuts and Jobs Act. The Company continues to evaluate its deferred tax assets each period to determine if a valuation allowance is required based on whether it is more likely than not that some portion of these deferred tax assets will not be realized. As of March 31, 2019, management concluded that it is more likely than not that a substantial portion of our deferred tax assets will be realized. As part of our analysis, we considered both positive and negative factors, including current quarter impairments, that impact profitability and whether those factors would lead to a change in the estimate of our deferred tax assets that may be realized in the future. Our conclusions on the valuation allowance and Internal Revenue Code Section 382 limitations related to our deferred tax assets remain consistent with the determinations we made during the period ended September 30, 2018, and such conclusions are based on similar company specific and industry factors to those discussed in Note 13 to the audited consolidated financial statements within our 2018 Annual Report.

Income Taxes

Income Tax Provision

The Company's income tax provision for quarterly interim periods is based on an estimated annual effective income tax rate calculated separately from the effect of significant, infrequent, or unusual items. The total income tax provision, including discontinued operations, was a tax benefit of $38.2 million and $42.1 million for the three and six months ended March 31, 2019, respectively, compared to an income tax expense of $1.0 million and $109.0 million for the three and six months ended March 31, 2018, respectively. The current fiscal year income tax benefit was primarily driven by (1) the loss from continuing operations due to the $148.6 million of impairments on our land inventory assets and (2) the completion of work necessary to claim an additional $5.4 million in tax credits related to prior fiscal years, partially offset by discrete impacts related to stock-based compensation. The tax expense for the six months ended March 31, 2018 was primarily driven by the remeasurement of the Company's deferred tax assets as a result of the enactment of the Tax Cuts and Jobs Act and several discrete tax items, including stock-based compensation. These items were partially offset by the loss incurred from continuing operations and completion of the work necessary to claim an additional $2.3 million in tax credits related to prior fiscal years.

Deferred Tax Assets and Liabilities

As of March 31, 2019, the net deferred tax asset is comprised of various tax attributes that include $9.6 million of minimum tax credit carryforwards. Beginning with the fiscal 2019 tax return, the Company will be able to make cash refund claims for significant portions of these credits due to the elimination of the alternative minimum tax in the Tax Cuts and Jobs Act.

The Company continues to evaluate its deferred tax assets each period to determine if a valuation allowance is required based on whether it is more likely than not that some portion of these deferred tax assets will not be realized. As of March 31, 2019, management concluded that it is more likely than not that a substantial portion of our deferred tax assets will be realized. As part of our analysis, we considered both positive and negative factors, including current quarter impairments, that impact profitability and whether those factors would lead to a change in the estimate of our deferred tax assets that may be realized in the future. Our conclusions on the valuation allowance and Internal Revenue Code Section 382 limitations related to our deferred tax assets remain consistent with the determinations we made during the period ended September 30, 2018, and such conclusions are based on similar company specific and industry factors to those discussed in Note 13 to the audited consolidated financial statements within our 2018 Annual Report.