CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Net Income	$ 88.9	$ 67.0
Cash flow hedging derivative instruments:
Net hedging gain arising during the period	17.2	18.9
Amounts reclassified into net income	(0.3)	(0.3)
Net gain on cash flow hedging derivative instruments	16.9	18.6
Other Comprehensive Income, Before Tax	16.9	18.6
Income Tax Expense Related to Items of Other Comprehensive Income	3.8	4.2
Other Comprehensive Income, Net of Tax	13.1	14.4
Comprehensive Income	102.0	81.4
Operating Revenues	512.6	566.9
Operating Expenses:
Natural gas	181.2	261.9
Operation and maintenance	111.6	116.6
Depreciation and amortization	50.8	47.5
Taxes, other than income taxes	36.1	38.6
Total Operating Expenses	379.7	464.6
Operating Income	132.9	102.3
Interest Expense, Net	25.7	26.7
Other Income, Net	4.3	5.7
Income Before Income Taxes	111.5	81.3
Income Tax Expense	22.6	14.3
Spire Missouri
Net Income	56.6	48.0
Cash flow hedging derivative instruments:
Other Comprehensive Income, Net of Tax	0.1	0.1
Comprehensive Income	56.7	48.1
Operating Revenues	355.5	374.0
Operating Expenses:
Natural gas	161.6	185.8
Operation and maintenance	62.9	65.5
Depreciation and amortization	30.4	29.0
Taxes, other than income taxes	25.1	26.7
Total Operating Expenses	280.0	307.0
Operating Income	75.5	67.0
Interest Expense, Net	11.7	13.2
Other Income, Net	2.7	1.0
Income Before Income Taxes	66.5	54.8
Income Tax Expense	$ 9.9	$ 6.8