Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Millions	Mar. 31, 2023		Sep. 30, 2022		Mar. 31, 2022
ASSETS
Utility Plant	$ 7,892.4		$ 7,664.9		$ 7,443.7
Less: Accumulated depreciation and amortization	2,358.5		2,294.5		2,241.9
Net Utility Plant	5,533.9		5,370.4		5,201.8
Non-utility Property (net of accumulated depreciation and amortization of $60.6, $50.7 and $41.3 at March 31, 2023, September 30, 2022, and March 31, 2022, respectively)	520.4		491.4		475.8
Other Investments	131.3		87.8		89.0
Total Other Property and Investments	651.7		579.2		564.8
Other Property and Investments	651.7		579.2		564.8
Current Assets:
Cash and cash equivalents	6.9		6.5		8.3
Utility	453.7		210.8		389.2
Other	166.0		443.8		245.4
Allowance for credit losses	(40.6)		(31.9)		(35.1)
Delayed customer billings	85.6		21.3		54.7
Accounts receivable:
Utility	453.7		210.8		389.2
Other	166.0		443.8		245.4
Allowance for credit losses	(40.6)		(31.9)		(35.1)
Delayed customer billings	85.6		21.3		54.7
Inventories:
Natural gas	146.8		371.8		125.0
Propane gas	8.6		8.6		8.6
Materials and supplies	48.9		41.9		34.7
Regulatory assets	143.0		355.4		164.0
Prepayments	32.5		41.1		26.6
Other current assets	60.2		122.7		67.9
Total Current Assets	1,111.6		1,592.0		1,089.3
Deferred Charges and Other Assets:
Goodwill	1,171.6		1,171.6		1,171.6
Regulatory assets	1,316.7		1,112.4		1,106.8
Other	263.5		258.1		267.0
Total Deferred Charges and Other Assets	2,751.8		2,542.1		2,545.4
Total Assets	10,049.0		10,083.7		9,401.3
Capitalization:
Preferred stock ($25.00 par value per share; 10.0 million depositary shares authorized, issued and outstanding at March 31, 2023, September 30, 2022, and March 31, 2022)	242.0		242.0		242.0
Common stock (par value $1.00 per share; 70.0 million shares authorized; 52.6 million, 52.5 million, and 52.1 million shares issued and outstanding at March 31, 2023, September 30, 2022, and March 31, 2022, respectively)	52.6		52.5		52.1
Paid-in capital	1,576.5		1,571.3		1,541.1
Retained earnings	1,089.5		905.5		992.3
Accumulated other comprehensive income	25.9		47.2		13.7
Total Shareholders' Equity	2,986.5		2,818.5		2,841.2
Temporary equity	18.8		13.1		11.8
Long-term debt (less current portion)	3,702.5		2,958.5		3,207.3
Total Capitalization	6,707.8		5,790.1		6,060.3
Current Liabilities:
Current portion of long-term debt	256.6		281.2		31.2
Notes payable	561.0		1,037.5		607.1
Accounts payable	232.3		617.4		367.5
Advance customer billings	6.8		18.7		6.3
Wages and compensation accrued	38.6		50.2		39.3
Customer deposits	28.3		28.2		29.4
Taxes accrued	79.9		90.1		67.4
Regulatory liabilities	5.3		3.7		3.2
Other current liabilities	198.1		226.6		244.4
Total Current Liabilities	1,406.9		2,353.6		1,395.8
Deferred Credits and Other Liabilities:
Deferred income taxes	737.9		675.1		666.5
Pension and postretirement benefit costs	158.6		163.0		199.2
Asset retirement obligations	531.5		520.9		530.1
Regulatory liabilities	360.3		418.2		400.4
Other noncurrent liabilities	146.0		162.8		149.0
Total Deferred Credits and Other Liabilities	1,934.3		1,940.0		1,945.2
Commitments and Contingencies (Note 11)
Total Capitalization and Liabilities	10,049.0		10,083.7		9,401.3
Spire Missouri [Member]
ASSETS
Utility Plant	4,731.2		4,550.4		4,416.9
Less: Accumulated depreciation and amortization	1,027.1		982.1		949.2
Net Utility Plant	3,704.1		3,568.3		3,467.7
Total Other Property and Investments	66.7		58.9		66.9
Other Property and Investments	66.7		58.9		66.9
Current Assets:
Utility	362.0		131.5		288.6
Other	32.5		44.5		35.3
Allowance for credit losses	(34.5)		(24.9)		(27.0)
Delayed customer billings	84.5		16.1		53.5
Accounts receivable:
Utility	362.0		131.5		288.6
Other	32.5		44.5		35.3
Allowance for credit losses	(34.5)		(24.9)		(27.0)
Delayed customer billings	84.5		16.1		53.5
Inventories:
Natural gas	86.7		215.3		80.9
Propane gas	8.6		8.6		8.6
Materials and supplies	24.4		22.0		18.6
Regulatory assets	62.7		288.1		112.7
Prepayments	18.5		23.3		16.0
Total Current Assets	649.2		728.2		590.8
Deferred Charges and Other Assets:
Goodwill	210.2		210.2		210.2
Regulatory assets	722.0		547.6		572.7
Other	107.2		105.0		126.4
Total Deferred Charges and Other Assets	1,039.4		862.8		909.3
Total Assets	5,459.4		5,218.2		5,034.7
Capitalization:
Retained earnings	1,061.3		931.9		960.5
Accumulated other comprehensive income	(2.5)		(2.7)		(4.0)
Total Shareholders' Equity	1,875.0	[1]	1,745.4	[1]	1,744.9
Long-term debt (less current portion)	1,784.5		1,387.7		1,637.1
Total Capitalization	3,659.5		3,133.1		3,382.0
Paid-in capital and common stock (par value $1.00 per share; 50.0 million shares authorized; 25,325, 25,325, and 24,929 shares issued and outstanding at March 31, 2023, September 30, 2022, and March 31, 2022, respectively)	816.2		816.2		788.4
Current Liabilities:
Current portion of long-term debt	250.0		250.0		0.0
Advance customer billings	0.0		7.0		0.0
Wages and compensation accrued	20.4		33.8		27.1
Customer deposits	6.0		6.5		7.7
Taxes accrued	47.2		50.4		37.4
Other current liabilities	52.5		45.6		49.4
Total Current Liabilities	726.9		970.9		502.6
Deferred Credits and Other Liabilities:
Deferred income taxes	533.3		500.1		498.9
Pension and postretirement benefit costs	99.8		115.5		132.9
Asset retirement obligations	112.8		110.6		146.3
Regulatory liabilities	276.9		331.8		313.7
Other noncurrent liabilities	50.2		56.2		58.3
Total Deferred Credits and Other Liabilities	1,073.0		1,114.2		1,150.1
Commitments and Contingencies (Note 11)
Total Capitalization and Liabilities	5,459.4		5,218.2		5,034.7
Spire Missouri [Member] | Related Party [Member]
Current Assets:
Associated companies	3.8		3.7		3.6
Accounts receivable:
Associated companies	3.8		3.7		3.6
Current Liabilities:
Notes payable	60.7		445.3		277.2
Accounts payable	11.3		13.3		6.9
Spire Missouri [Member] | Nonrelated Party [Member]
Current Liabilities:
Notes payable	200.0		0.0		0.0
Accounts payable	78.8		119.0		96.9
Spire Alabama Inc [Member]
ASSETS
Utility Plant	2,781.4		2,732.6		2,643.9
Less: Accumulated depreciation and amortization	1,208.7		1,184.1		1,154.0
Net Utility Plant	1,572.7		1,548.5		1,489.9
Current Assets:
Cash and cash equivalents	1.0		2.4		0.2
Utility	75.4		69.9		86.0
Other	5.3		6.5		5.6
Allowance for credit losses	(5.3)		(6.3)		(7.1)
Delayed customer billings	1.0		4.8		1.2
Accounts receivable:
Utility	75.4		69.9		86.0
Other	5.3		6.5		5.6
Allowance for credit losses	(5.3)		(6.3)		(7.1)
Delayed customer billings	1.0		4.8		1.2
Inventories:
Natural gas	41.4		72.5		32.0
Materials and supplies	20.5		16.3		13.1
Regulatory assets	64.8		56.9		41.0
Prepayments	3.8		5.8		3.6
Total Current Assets	208.7		230.1		176.3
Deferred Charges and Other Assets:
Regulatory assets	568.3		538.2		506.7
Other	81.9		81.3		63.6
Total Deferred Charges and Other Assets	650.2		630.5		579.4
Total Assets	2,431.6		2,409.1		2,245.6
Deferred income taxes	0.0		11.0		9.1
Capitalization:
Retained earnings	645.3		589.1		611.2
Total Shareholders' Equity	935.2		906.0		934.1
Long-term debt (less current portion)	745.7		571.5		571.4
Total Capitalization	1,680.9		1,477.5		1,505.5
Paid-in capital and common stock (par value $1.00 per share; 50.0 million shares authorized; 25,325, 25,325, and 24,929 shares issued and outstanding at March 31, 2023, September 30, 2022, and March 31, 2022, respectively)	289.9		316.9		322.9
Current Liabilities:
Accounts payable	29.8		85.6		50.8
Advance customer billings	5.3		9.9		5.2
Wages and compensation accrued	5.4		7.6		5.6
Customer deposits	19.6		19.0		19.0
Taxes accrued	26.4		31.3		24.3
Other current liabilities	15.7		22.4		12.3
Total Current Liabilities	230.5		441.1		280.0
Deferred Credits and Other Liabilities:
Deferred income taxes	12.3		0.0		0.0
Pension and postretirement benefit costs	52.8		40.5		59.1
Asset retirement obligations	406.9		398.7		370.0
Regulatory liabilities	21.5		23.0		24.7
Other noncurrent liabilities	26.7		28.3		6.3
Total Deferred Credits and Other Liabilities	520.2		490.5		460.1
Total Capitalization and Liabilities	2,431.6		2,409.1		2,245.6
Spire Alabama Inc [Member] | Related Party [Member]
Current Assets:
Associated companies	0.8		1.3		0.7
Accounts receivable:
Associated companies	0.8		1.3		0.7
Current Liabilities:
Notes payable	121.3		260.9		156.6
Accounts payable	$ 7.0		$ 4.4		$ 6.2

[1] Accumulated other comprehensive income (loss)