Note 2 - Revenue - Taxes Associated with Natural Gas Utility Services (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2024 |
Jun. 30, 2023 |
Jun. 30, 2024 |
Jun. 30, 2023 |
|
Gross Receipts Tax Amounts | $ 22.4 | $ 26.0 | $ 113.5 | $ 116.6 |
Spire Missouri [Member] | ||||
Gross Receipts Tax Amounts | 16.3 | 18.9 | 82.8 | 86.6 |
Spire Alabama Inc [Member] | ||||
Gross Receipts Tax Amounts | $ 5.3 | $ 6.1 | $ 26.3 | $ 25.5 |