Note 7 - Fair Value of Financial Instruments (Tables)

6 Months Ended

Mar. 31, 2024

Notes Tables

Fair Value, by Balance Sheet Grouping [Table Text Block]

					Classification of Estimated Fair Value
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)
Spire
As of March 31, 2024
Cash and cash equivalents	$	25.6	$	25.6	$	25.6	$	—
Notes payable		786.0		786.0		—		786.0
Long-term debt, including current portion		3,728.4		3,452.0		—		3,452.0
As of September 30, 2023
Cash and cash equivalents	$	5.6	$	5.6	$	5.6	$	—
Notes payable		955.5		955.5		—		955.5
Long-term debt, including current portion		3,710.6		3,270.2		—		3,270.2
As of March 31, 2023
Cash and cash equivalents	$	6.9	$	6.9	$	6.9	$	—
Notes payable		561.0		561.0		—		561.0
Long-term debt, including current portion		3,959.1		3,704.2		—		3,704.2
Spire Missouri
As of March 31, 2024
Notes payable	$	200.0	$	200.0	$	—	$	200.0
Notes payable – associated companies		243.9		243.9		—		243.9
Long-term debt, including current portion		1,786.2		1,649.4		—		1,649.4
As of September 30, 2023
Cash and cash equivalents	$	0.8	$	0.8	$	0.8	$	—
Notes payable – associated companies		540.6		540.6		—		540.6
Long-term debt		1,785.4		1,592.4		—		1,592.4
As of March 31, 2023
Notes payable	$	200.0	$	200.0	$	—	$	200.0
Notes payable – associated companies		60.7		60.7		—		60.7
Long-term debt, including current portion		2,034.5		1,930.2		—		1,930.2
Spire Alabama
As of March 31, 2024
Cash and cash equivalents	$	1.8	$	1.8	$	1.8	$	—
Notes payable – associated companies		37.4		37.4		—		37.4
Long-term debt		746.1		685.3		—		685.3
As of September 30, 2023
Cash and cash equivalents	$	1.2	$	1.2	$	1.2	$	—
Notes payable – associated companies		124.1		124.1		—		124.1
Long-term debt		745.9		648.0		—		648.0
As of March 31, 2023
Cash and cash equivalents	$	1.0	$	1.0	$	1.0	$	—
Notes payable – associated companies		121.3		121.3		—		121.3
Long-term debt		745.7		696.6		—		696.6