Revenue (Tables)

6 Months Ended

Mar. 31, 2025

Revenue from Contract with Customer [Abstract]

Schedule of Revenue Disaggregated by Source and Customer Type

The following tables show revenue disaggregated by source and customer type.

	Three Months Ended March 31,						Six Months Ended  March 31,
	2025			2024			2025			2024
Spire
Gas Utility:
Residential	$	679.4		$	729.5		$	1,090.9		$	1,222.3
Commercial and industrial		224.9			267.9			358.6			425.8
Transportation		37.4			36.8			72.0			69.4
Off-system and other incentive		22.7			13.0			34.2			19.4
Other customer revenue		12.9			8.2			13.7			13.7
Total revenue from contracts with customers		977.3			1,055.4			1,569.4			1,750.6
Changes in accrued revenue under alternative revenue programs		(7.1	)		17.3			14.3			37.3
Total Gas Utility operating revenues		970.2			1,072.7			1,583.7			1,787.9
Gas Marketing		53.6			46.0			86.6			82.3
Midstream		38.4			21.5			71.9			36.4
Other		4.9			4.1			9.6			8.2
Total before eliminations		1,067.1			1,144.3			1,751.8			1,914.8
Intersegment eliminations (see Note 10, Information by Operating Segment)		(15.8	)		(15.8	)		(31.4	)		(29.7	)
Total Operating Revenues	$	1,051.3		$	1,128.5		$	1,720.4		$	1,885.1

Spire Missouri
Residential	$	490.0		$	532.9	$	811.8	$	921.7
Commercial and industrial		147.7			185.7		241.5		295.9
Transportation		10.8			10.1		20.2		19.1
Off-system and other incentive		19.5			12.3		29.4		16.4
Other customer revenue		4.9			5.0		7.7		7.5
Total revenue from contracts with customers		672.9			746.0		1,110.6		1,260.6
Changes in accrued revenue under alternative revenue programs		(1.3	)		20.5		18.5		41.3
Total Operating Revenues	$	671.6		$	766.5	$	1,129.1	$	1,301.9

Spire Alabama
Residential	$	159.5		$	169.3		$	231.9		$	253.7
Commercial and industrial		62.5			68.8			91.4			103.5
Transportation		23.8			24.0			46.3			44.8
Off-system and other incentive		3.2			0.7			4.8			3.0
Other customer revenue		7.0			0.7			3.8			1.6
Total revenue from contracts with customers		256.0			263.5			378.2			406.6
Changes in accrued revenue under alternative revenue programs		(3.6	)		(4.0	)		(5.4	)		(5.0	)
Total Operating Revenues	$	252.4		$	259.5		$	372.8		$	401.6

Schedule of Gross Receipts Taxes Associated Revenue

	Three Months Ended March 31,				Six Months Ended  March 31,
	2025		2024		2025		2024
Spire	$	55.2	$	60.0	$	82.0	$	91.1
Spire Missouri		39.9		44.0		59.4		66.5
Spire Alabama		13.4		14.1		19.1		21.0