Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2022		Jun. 30, 2021
Operating Activities:
Net Income	$ 227.9		$ 281.6
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	176.2		155.4
Deferred income taxes and investment tax credits	57.0		68.4
Changes in assets and liabilities:
Accounts receivable	9.1		(248.6)
Inventories	4.9		(22.4)
Regulatory assets and liabilities	(323.8)		(3.1)
Accounts payable	180.3		79.7
Delayed/advance customer billings, net	(60.8)		(34.8)
Taxes accrued	(2.2)		(3.3)
Other assets and liabilities	(70.1)		(61.7)
Other	6.1		9.5
Net cash provided by operating activities	204.6		220.7
Delayed/advance customer billings, net	(60.8)		(34.8)
Investing Activities:
Capital expenditures	(402.5)		(463.2)
Other	4.2		1.5
Net cash used in investing activities	(398.3)		(461.7)
Financing Activities:
Issuance of long-term debt	300.0		629.1
Repayment of long-term debt	(55.8)		(60.4)
Issuance (repayment) of short-term debt, net	37.2		(187.0)
Issuance of common stock	51.9		0.6
Dividends paid on common stock	(105.9)		(99.6)
Dividends paid on preferred stock	(11.1)		(11.1)
Other financing activities	(3.8)		(10.8)
Net cash provided by financing activities	212.5		260.8
Net Increase in Cash, Cash Equivalents, and Restricted Cash	18.8		19.8
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	11.3		4.1
Cash, Cash Equivalents, and Restricted Cash at End of Period	30.1		23.9
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(80.2)		(65.9)
Income taxes	(0.7)		(0.4)
Spire Missouri [Member]
Operating Activities:
Net Income	135.1	[1]	152.8
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	107.4		93.0
Deferred income taxes and investment tax credits	23.8		26.7
Changes in assets and liabilities:
Accounts receivable	167.6		(212.1)
Inventories	29.4		(36.0)
Regulatory assets and liabilities	(260.8)		(17.9)
Accounts payable	25.8		(1.1)
Delayed/advance customer billings, net	(61.0)		(34.8)
Taxes accrued	(0.2)		(5.2)
Other assets and liabilities	(48.5)		(95.8)
Other	1.0		0.5
Net cash provided by operating activities	119.6		(129.9)
Delayed/advance customer billings, net	(61.0)		(34.8)
Investing Activities:
Capital expenditures	(258.7)		(279.2)
Other	2.6		1.1
Net cash used in investing activities	(256.1)		(278.1)
Financing Activities:
Issuance of long-term debt	300.0		304.1
Repayment of long-term debt	0.0		(55.0)
Issuance (repayment) of short-term debt, net	(250.0)		250.0
Issuance of common stock	51.1		0.0
Other financing activities	(2.1)		(3.1)
Net cash provided by financing activities	143.5		412.3
Net Increase in Cash, Cash Equivalents, and Restricted Cash	7.0		4.3
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	0.0		0.0
Cash, Cash Equivalents, and Restricted Cash at End of Period	7.0		4.3
Borrowings from (repayments to) Spire, net	44.5		(83.7)
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(43.9)		(33.1)
Income taxes	0.0		0.0
Spire Alabama Inc [Member]
Operating Activities:
Net Income	85.1		83.5
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	50.1		46.3
Deferred income taxes and investment tax credits	28.7		28.3
Changes in assets and liabilities:
Accounts receivable	(42.7)		(10.4)
Inventories	(38.1)		(3.3)
Regulatory assets and liabilities	(67.4)		7.1
Accounts payable	41.6		1.9
Delayed/advance customer billings, net	(0.1)		(0.1)
Taxes accrued	(1.2)		(0.2)
Other assets and liabilities	(17.4)		(8.2)
Other	0.0		0.2
Net cash provided by operating activities	38.6		145.1
Delayed/advance customer billings, net	(0.1)		(0.1)
Investing Activities:
Capital expenditures	(105.0)		(125.5)
Other	0.7		0.6
Net cash used in investing activities	(104.3)		(124.9)
Financing Activities:
Issuance of long-term debt	0.0		150.0
Repayment of long-term debt	(50.0)		0.0
Dividends paid on common stock	(16.0)		(16.5)
Other financing activities	0.0		(0.9)
Net cash provided by financing activities	69.4		(10.7)
Net Increase in Cash, Cash Equivalents, and Restricted Cash	3.7		9.5
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	0.0		0.0
Cash, Cash Equivalents, and Restricted Cash at End of Period	3.7		9.5
Borrowings from (repayments to) Spire, net	147.4		(121.3)
Return of capital to Spire	(12.0)		(22.0)
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(14.7)		(13.2)
Income taxes	$ 0.0		$ 0.0

[1] Accumulated other comprehensive income (loss)