Income Taxes	6 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	12. INCOME TAXES The Tax Cuts and Jobs Act (“TCJA”) was signed into law on December 22, 2017, with an effective date of January 1, 2018, for substantially all of the provisions. The specific provisions related to regulated public utilities in the TCJA generally allow for the continued deductibility of interest expense, the elimination of full expensing for tax purposes of certain property acquired after September 27, 2017, and the continuation of certain rate normalization requirements for accelerated depreciation benefits. The Department of the Treasury (“Treasury”) has issued proposed regulations associated with the deductibility of interest expense, but further clarification of certain provisions is expected. Treasury has also issued proposed regulations on bonus depreciation which allow full expensing for certain property acquired in tax years beginning prior to January 1, 2018. As indicated in Note 1, Summary of Significant Accounting Policies, the Company’s regulated operations accounting for income taxes is impacted by ASC 980, Regulated Operations. Reductions in deferred income tax balances due to the reduction in the corporate income tax rate will result in amounts previously collected from utility customers for these deferred taxes to be refundable to such customers, generally through reductions in future rates. The TCJA includes provisions that stipulate how these excess deferred taxes are to be passed back to customers for certain accelerated tax depreciation benefits. In the third quarter of fiscal 2018, the MoPSC Amended Report and Order took effect and the estimated excess accumulated deferred income tax began to be returned to customers in rates. The amount being returned is estimated with a tracker established to defer the difference from the estimated amounts to the actual amounts once the actual amounts have been calculated. During the three and six months ended March 31, 2019, Spire Missouri returned excess accumulated deferred taxes of $2.1 and $4.2, respectively. The treatment for accumulated deferred income tax balances for Spire Alabama, Spire Gulf and Spire Mississippi is yet to be determined by state regulators.

Income Taxes

6 Months Ended

Mar. 31, 2019

12. INCOME TAXES

The Tax Cuts and Jobs Act (“TCJA”) was signed into law on December 22, 2017, with an effective date of January 1, 2018, for substantially all of the provisions. The specific provisions related to regulated public utilities in the TCJA generally allow for the continued deductibility of interest expense, the elimination of full expensing for tax purposes of certain property acquired after September 27, 2017, and the continuation of certain rate normalization requirements for accelerated depreciation benefits. The Department of the Treasury (“Treasury”) has issued proposed regulations associated with the deductibility of interest expense, but further clarification of certain provisions is expected. Treasury has also issued proposed regulations on bonus depreciation which allow full expensing for certain property acquired in tax years beginning prior to January 1, 2018.

As indicated in Note 1, Summary of Significant Accounting Policies, the Company’s regulated operations accounting for income taxes is impacted by ASC 980, Regulated Operations. Reductions in deferred income tax balances due to the reduction in the corporate income tax rate will result in amounts previously collected from utility customers for these deferred taxes to be refundable to such customers, generally through reductions in future rates. The TCJA includes provisions that stipulate how these excess deferred taxes are to be passed back to customers for certain accelerated tax depreciation benefits. In the third quarter of fiscal 2018, the MoPSC Amended Report and Order took effect and the estimated excess accumulated deferred income tax began to be returned to customers in rates. The amount being returned is estimated with a tracker established to defer the difference from the estimated amounts to the actual amounts once the actual amounts have been calculated. During the three and six months ended March 31, 2019, Spire Missouri returned excess accumulated deferred taxes of $2.1 and $4.2, respectively. The treatment for accumulated deferred income tax balances for Spire Alabama, Spire Gulf and Spire Mississippi is yet to be determined by state regulators.