CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net (Loss) Income	$ (92.3)	$ (3.0)	$ 108.3	$ 218.9
Cash flow hedging derivative instruments:
Net hedging gain (loss) arising during the period	1.4	(12.3)	(20.8)	(30.4)
Amounts reclassified into net income	(0.3)	(0.3)	(2.8)	(1.0)
Net gain (loss) on cash flow hedging derivative instruments	1.1	(12.6)	(23.6)	(31.4)
Net gain (loss) on defined benefit pension and other postretirement plans		0.1	(0.1)	0.2
Net unrealized gain on available for sale securities				0.1
Other Comprehensive Income (Loss), Before Tax	1.1	(12.5)	(23.7)	(31.1)
Income Tax Expense (Benefit) Related to Items of Other Comprehensive Income (Loss)	0.1	(3.1)	(5.4)	(7.5)
Other Comprehensive Income (Loss), Net of Tax	1.0	(9.4)	(18.3)	(23.6)
Comprehensive (Loss) Income	(91.3)	(12.4)	90.0	195.3
Operating Revenues:
Gas Utility	305.7	301.4	1,515.4	1,651.9
Total Operating Revenues	321.1	321.3	1,603.5	1,726.8
Gas Utility
Natural and propane gas	70.7	75.5	534.3	664.6
Other operation and maintenance expenses	112.5	111.2	311.6	323.2
Depreciation and amortization	47.8	45.1	141.2	133.2
Taxes, other than income taxes	31.7	29.7	121.3	126.3
Total Operating Expenses	427.6	308.0	1,397.2	1,398.9
Operating (Loss) Income	(106.5)	13.3	206.3	327.9
Interest Expense, Net	26.4	25.6	80.3	79.1
Other Income (Expense), Net	13.0	6.4	(0.8)	15.3
(Loss) Income Before Income Taxes	(119.9)	(5.9)	125.2	264.1
Income Tax Expense (Benefit)	(27.6)	(2.9)	16.9	45.2
Net (Loss) Income	(92.3)	(3.0)	108.3	218.9
Other Comprehensive Income (Loss), Net of Tax	1.0	(9.4)	(18.3)	(23.6)
Comprehensive (Loss) Income	(91.3)	(12.4)	90.0	195.3
Spire Missouri
Net (Loss) Income	6.5	1.1	129.0	132.3
Cash flow hedging derivative instruments:
Other Comprehensive Income (Loss), Net of Tax	0.1	0.1		0.1
Comprehensive (Loss) Income	6.6	1.2	129.0	132.4
Operating Revenues:
Gas Utility	203.9	191.4	1,035.4	1,161.2
Total Operating Revenues	203.9	191.4	1,035.4	1,161.2
Gas Utility
Natural and propane gas	68.9	63.1	478.3	600.3
Other operation and maintenance expenses	75.6	68.2	191.9	202.0
Depreciation and amortization	29.7	28.0	88.0	83.0
Taxes, other than income taxes	22.7	19.9	85.5	89.9
Total Operating Expenses	196.9	179.2	843.7	975.2
Operating (Loss) Income	7.0	12.2	191.7	186.0
Interest Expense, Net	11.9	11.9	37.8	37.2
Other Income (Expense), Net	11.8	0.5	(8.1)	2.3
(Loss) Income Before Income Taxes	6.9	0.8	145.8	151.1
Income Tax Expense (Benefit)	0.4	(0.3)	16.8	18.8
Net (Loss) Income	6.5	1.1	129.0	132.3
Other Comprehensive Income (Loss), Net of Tax	0.1	0.1		0.1
Comprehensive (Loss) Income	$ 6.6	$ 1.2	$ 129.0	$ 132.4