CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating Activities:
Net Income	$ 67.0	$ 67.3
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	47.5	44.2
Deferred income taxes and investment tax credits	14.3	12.7
Changes in assets and liabilities:
Accounts receivable	(162.5)	(260.5)
Inventories	11.1	(2.5)
Regulatory assets and liabilities	45.6	44.7
Accounts payable	42.6	158.0
Delayed/advance customer billings, net	(3.5)	(6.9)
Taxes accrued	(24.9)	(19.1)
Other assets and liabilities	30.3	32.9
Other	(3.0)	(0.4)
Net cash provided by operating activities	64.5	70.4
Investing Activities:
Capital expenditures	(192.3)	(206.8)
Business acquisitions	0.0	(7.9)
Other	(0.3)	(1.5)
Net cash used in investing activities	(192.6)	(216.2)
Financing Activities:
Issuance of long-term debt	510.0	100.0
Repayment of long-term debt	(100.0)	(9.1)
(Repayment) issuance of short-term debt, net	(224.2)	72.5
Issuance of common stock	2.3	0.4
Dividends paid on common stock	(34.7)	(28.8)
Dividends paid on preferred stock	(3.7)	0.0
Other	(5.9)	(2.2)
Net cash provided by financing activities	143.8	132.8
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	15.7	(13.0)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	5.8	21.4
Cash and Cash Equivalents at End of Period	21.5	8.4
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(11.6)	(13.9)
Income taxes	0.0	0.0
Spire Missouri
Operating Activities:
Net Income	48.0	51.2
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	29.0	27.2
Deferred income taxes and investment tax credits	6.8	7.4
Changes in assets and liabilities:
Accounts receivable	(96.9)	(124.6)
Inventories	5.5	(2.5)
Regulatory assets and liabilities	32.8	32.0
Accounts payable	26.9	50.9
Delayed/advance customer billings, net	(2.4)	(4.4)
Taxes accrued	(21.7)	(17.4)
Other assets and liabilities	16.9	29.4
Other	0.2	1.2
Net cash provided by operating activities	45.1	50.4
Investing Activities:
Capital expenditures	(102.2)	(92.0)
Other	0.0	0.6
Net cash used in investing activities	(102.2)	(91.4)
Financing Activities:
Issuance of long-term debt	275.0	100.0
Repayment of long-term debt	(100.0)	0.0
Repayments to Spire, net	(98.3)	(37.3)
Dividends paid on common stock	(11.3)	(18.8)
Other	(1.6)	0.0
Net cash provided by financing activities	63.8	43.9
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	6.7	2.9
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	2.6	2.0
Cash and Cash Equivalents at End of Period	9.3	4.9
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(7.5)	(8.3)
Income taxes	0.0	0.0
Spire Alabama
Operating Activities:
Net Income	13.2	10.3
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	14.3	13.6
Deferred income taxes and investment tax credits	4.5	3.5
Changes in assets and liabilities:
Accounts receivable	(34.3)	(52.0)
Inventories	4.2	3.2
Regulatory assets and liabilities	11.1	11.5
Accounts payable	(0.8)	29.7
Delayed/advance customer billings, net	(0.6)	(3.2)
Taxes accrued	(1.3)	(1.7)
Other assets and liabilities	0.6	2.8
Other	(2.7)	(0.4)
Net cash provided by operating activities	8.2	17.3
Investing Activities:
Capital expenditures	(38.7)	(30.1)
Other	(1.4)	(0.4)
Net cash used in investing activities	(40.1)	(30.5)
Financing Activities:
Issuance of long-term debt	100.0	0.0
Repayments to Spire, net	(61.6)	21.7
Dividends paid on common stock	(6.0)	(8.5)
Other	(0.5)	0.0
Net cash provided by financing activities	31.9	13.2
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	0.0	0.0
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	0.0	0.0
Cash and Cash Equivalents at End of Period	0.0	0.0
Supplemental disclosure of cash paid for:
Interest, net of amounts capitalized	(2.9)	(3.6)
Income taxes	$ 0.0	$ 0.0