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INCOME TAXES (Tables) | 12 Months Ended
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Sep. 30, 2017
Income Tax Contingency [Line Items] |
Net Provision For Income Tax | The Company’s provision for income taxes charged during the fiscal years ended September 30, 2017, 2016, and 2015 are as follows:
| 2017 |  | 2016 |  | 2015
Federal |  |  |  |  |
Current | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | (3.3 | )
Deferred | 67.7 |  |  | 62.0 |  |  | 58.8 |
Investment tax credits | (0.2 | ) |  | (0.2 | ) |  | (0.2 | )
State and local |  |  |  |  |
Current | 0.5 |  |  | 0.6 |  |  | — |
Deferred | 9.5 |  |  | 7.0 |  |  | 6.9 |
Total income tax expense | $ | 77.6 |  |  | $ | 69.5 |  |  | $ | 62.2 |
Effective income tax rate variation from stated tax rate | The Company’s effective income tax rate varied from the federal statutory income tax rate for each year due to the following:
| 2017 |  | 2016 |  | 2015
Federal income tax statutory rate | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State and local income taxes, net of federal income tax benefits | 2.8 |  |  | 2.8 |  |  | 3.0 |
Certain expenses capitalized on books and deducted on tax return | (2.3 | ) |  | (3.4 | ) |  | (3.7 | )
Taxes related to prior years | (0.9 | ) |  | (0.2 | ) |  | (0.6 | )
Other items – net * | (2.2 | ) |  | (1.7 | ) |  | (2.5 | )
Effective income tax rate | 32.4 | % |  | 32.5 | % |  | 31.2 | %
* Other consists primarily of property adjustments.
Significant Items in Net Deferred Tax Liability | The Company’s significant items comprising the net deferred tax liability recorded in the Consolidated Balance Sheets as of September 30 are as follows:
| 2017 |  | 2016
Deferred tax assets: |  |  |
Reserves not currently deductible | $ | 31.5 |  |  | $ | 21.3 |
Pension and other postretirement benefits | 58.6 |  |  | 68.3 |
Operating losses | 169.6 |  |  | 102.3 |
Other | 26.0 |  |  | — |
Deferred tax assets | 285.7 |  |  | 191.9 |
Less: valuation allowance | 0.5 |  |  | 0.9 |
Total deferred tax assets | 285.2 |  |  | 191.0 |
Deferred tax liabilities: |  |  |
Relating to property | 728.3 |  |  | 623.1 |
Regulatory pension and other postretirement benefits | 108.0 |  |  | 106.8 |
Deferred gas costs | 30.6 |  |  | 20.0 |
Other** | 125.8 |  |  | 48.4 |
Total deferred tax liabilities | 992.7 |  |  | 798.3 |
Net deferred tax liability | $ | 707.5 |  |  | $ | 607.3 |
Unrecognized Tax Benefit Reconciliation | The following table presents a reconciliation of the beginning and ending balances of the Company’s unrecognized tax benefits:
| 2017 |  | 2016 |  | 2015
Unrecognized tax benefits, beginning of year | $ | 10.0 |  |  | $ | 7.1 |  |  | $ | 4.6 |
Increases related to tax positions taken in current year | 2.4 |  |  | 3.4 |  |  | 2.9 |
Reductions due to lapse of applicable statute of limitations | (1.4 | ) |  | (0.5 | ) |  | (0.4 | )
Unrecognized tax benefits, end of year | $ | 11.0 |  |  | $ | 10.0 |  |  | $ | 7.1 |
Spire Missouri |
Income Tax Contingency [Line Items] |
Net Provision For Income Tax | ’s provision for income taxes charged during the fiscal years ended September 30, 2017, 2016, and 2015 are as follows:
| 2017 |  | 2016 |  | 2015
Federal |  |  |  |  |
Current | $ | — |  |  | $ | — |  |  | $ | (2.1 | )
Deferred | 42.0 |  |  | 37.5 |  |  | 40.9 |
Investment tax credits | (0.2 | ) |  | (0.2 | ) |  | (0.2 | )
State and local |  |  |  |  |
Current | — |  |  | 0.1 |  |  | (0.1 | )
Deferred | 5.7 |  |  | 8.0 |  |  | 4.7 |
Total income tax expense | $ | 47.5 |  |  | $ | 45.4 |  |  | $ | 43.2 |
Effective income tax rate variation from stated tax rate | ’s effective income tax rate varied from the federal statutory income tax rate for each year due to the following:
| 2017 |  | 2016 |  | 2015
Federal income tax statutory rate | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State and local income taxes, net of federal income tax benefits | 2.8 |  |  | 2.8 |  |  | 2.8 |
Certain expenses capitalized on books and deducted on tax return | (3.5 | ) |  | (4.8 | ) |  | (4.9 | )
Taxes related to prior years | (1.4 | ) |  | (0.2 | ) |  | (0.8 | )
Other items – net * | (3.3 | ) |  | (2.8 | ) |  | (3.0 | )
Effective income tax rate | 29.6 | % |  | 30.0 | % |  | 29.1 | %
* Other consists primarily of property adjustments.
Significant Items in Net Deferred Tax Liability | ’s significant items comprising the net deferred tax liability reported in the Balance Sheets as of September 30 are as follows:
| 2017 |  | 2016
Deferred tax assets: |  |  |
Reserves not currently deductible | $ | 25.3 |  |  | $ | 14.9 |
Pension and other postretirement benefits | 52.7 |  |  | 56.9 |
Operating losses | 52.0 |  |  | 29.9 |
Deferred tax assets | 130.0 |  |  | 101.7 |
Less: valuation allowance | 0.5 |  |  | 0.9 |
Total deferred tax assets | 129.5 |  |  | 100.8 |
Deferred tax liabilities: |  |  |
Relating to utility property | 563.2 |  |  | 497.0 |
Regulatory pension and other postretirement benefits | 108.0 |  |  | 106.8 |
Deferred gas costs | 25.0 |  |  | 20.0 |
Other | 57.1 |  |  | 33.9 |
Total deferred tax liabilities | 753.3 |  |  | 657.7 |
Net deferred tax liability | $ | 623.8 |  |  | $ | 556.9 |
Unrecognized Tax Benefit Reconciliation | The following table presents a reconciliation of the beginning and ending balances of Spire Missouri unrecognized tax benefits:
| 2017 |  | 2016 |  | 2015
Unrecognized tax benefits, beginning of year | $ | 9.7 |  |  | $ | 6.9 |  |  | $ | 4.2 |
Increases related to tax positions taken in current year | 2.4 |  |  | 3.3 |  |  | 2.9 |
Reductions due to lapse of applicable statute of limitations | (1.4 | ) |  | (0.5 | ) |  | (0.2 | )
Unrecognized tax benefits, end of year | $ | 10.7 |  |  | $ | 9.7 |  |  | $ | 6.9 |
Spire Alabama |
Income Tax Contingency [Line Items] |
Net Provision For Income Tax | ’s provision for income taxes charged during the fiscal years ended September 30, 2017, 2016, and 2015, are as follows:
| 2017 |  | 2016 |  | 2015
Federal |  |  |  |  |
Current | $ | — |  |  | $ | (0.8 | ) |  | $ | — |
Deferred | 31.6 |  |  | 29.4 |  |  | 25.9 |
State and local |  |  |  |  |
Current | — |  |  | — |  |  | 0.1 |
Deferred | 4.2 |  |  | 3.8 |  |  | 3.3 |
Total income tax expense | $ | 35.8 |  |  | $ | 32.4 |  |  | $ | 29.3 |
Effective income tax rate variation from stated tax rate | ’s effective income tax rate varied from the federal statutory income tax rate for each year due to the following:
| 2017 |  | 2016 |  | 2015
Federal income tax statutory rate | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State and local income taxes, net of federal income tax benefits | 2.8 |  |  | 2.8 |  |  | 2.8 |
Other items – net | 0.3 |  |  | 0.1 |  |  | 0.1 |
Effective income tax rate | 38.1 | % |  | 37.9 | % |  | 37.9 | %
Significant Items in Net Deferred Tax Liability | ’s significant items comprising the net deferred tax asset reported in the Balance Sheets as of September 30 are as follows:
| 2017 |  | 2016
Deferred tax assets: |  |  |
Reserves not currently deductible | $ | 6.0 |  |  | $ | 6.3 |
Pension and other postretirement benefits | 4.4 |  |  | 11.4 |
Goodwill | 214.4 |  |  | 233.4 |
Operating losses | 88.3 |  |  | 60.2 |
Total deferred tax assets | 313.1 |  |  | 311.3 |
Deferred tax liabilities: |  |  |
Relating to utility property | 119.3 |  |  | 87.6 |
Other | 8.2 |  |  | 2.3 |
Total deferred tax liabilities | 127.5 |  |  | 89.9 |
Net deferred tax asset | $ | 185.6 |  |  | $ | 221.4 |

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