Note 9 - Pension Plans and Other Postretirement Benefits (Tables)

6 Months Ended

Mar. 31, 2024

Notes Tables

Schedule of Net Benefit Costs [Table Text Block]

	Three Months Ended March 31,						Six Months Ended March 31,
	2024			2023			2024			2023
Spire
Service cost – benefits earned during the period	$	3.9		$	3.9		$	7.9		$	8.0
Interest cost on projected benefit obligation		6.6			5.9			13.4			12.3
Expected return on plan assets		(6.1	)		(5.7	)		(12.4	)		(12.1	)
Amortization of prior service credit		(1.2	)		(1.2	)		(2.3	)		(2.3	)
Amortization of actuarial loss		1.6			1.6			3.2			3.2
Loss on lump-sum settlements		—			—			—			8.6
Subtotal		4.8			4.5			9.8			17.7
Regulatory adjustment		8.8			10.4			17.5			12.2
Net pension cost	$	13.6		$	14.9		$	27.3		$	29.9
Spire Missouri
Service cost – benefits earned during the period	$	2.6		$	2.9		$	5.2		$	5.7
Interest cost on projected benefit obligation		4.7			4.4			9.5			8.9
Expected return on plan assets		(4.2	)		(4.5	)		(8.5	)		(9.0	)
Amortization of prior service credit		(0.5	)		(0.5	)		(1.0	)		(1.0	)
Amortization of actuarial loss		1.4			1.6			2.9			3.1
Subtotal		4.0			3.9			8.1			7.7
Regulatory adjustment		6.3			8.1			12.6			16.2
Net pension cost	$	10.3		$	12.0		$	20.7		$	23.9
Spire Alabama
Service cost – benefits earned during the period	$	1.1		$	0.8		$	2.3		$	1.9
Interest cost on projected benefit obligation		1.2			0.8			2.5			2.1
Expected return on plan assets		(1.2	)		(0.5	)		(2.4	)		(1.6	)
Amortization of prior service credit		(0.6	)		(0.6	)		(1.2	)		(1.2	)
Amortization of actuarial loss		0.3			0.2			0.5			0.3
Loss on lump-sum settlements		—			—			—			8.6
Subtotal		0.8			0.7			1.7			10.1
Regulatory adjustment		2.3			2.1			4.5			(4.4	)
Net pension cost	$	3.1		$	2.8		$	6.2		$	5.7

	Three Months Ended March 31,						Six Months Ended March 31,
	2024			2023			2024			2023
Spire
Service cost – benefits earned during the period	$	1.0		$	1.2		$	2.1		$	2.4
Interest cost on accumulated postretirement benefit obligation		2.4			2.2			4.5			4.3
Expected return on plan assets		(4.2	)		(3.9	)		(8.2	)		(7.8	)
Amortization of prior service cost		0.1			—			0.2			0.1
Amortization of actuarial gain		(1.1	)		(1.1	)		(2.1	)		(2.1	)
Subtotal		(1.8	)		(1.6	)		(3.5	)		(3.1	)
Regulatory adjustment		0.3			0.2			0.5			0.3
Net postretirement benefit income	$	(1.5	)	$	(1.4	)	$	(3.0	)	$	(2.8	)
Spire Missouri
Service cost – benefits earned during the period	$	0.9		$	1.0		$	1.8		$	2.0
Interest cost on accumulated postretirement benefit obligation		1.7			1.7			3.3			3.3
Expected return on plan assets		(2.7	)		(2.7	)		(5.4	)		(5.3	)
Amortization of prior service cost		0.1			0.1			0.3			0.3
Amortization of actuarial gain		(0.9	)		(0.8	)		(1.8	)		(1.6	)
Subtotal		(0.9	)		(0.7	)		(1.8	)		(1.3	)
Regulatory adjustment		0.7			0.7			1.3			1.3
Net postretirement benefit income	$	(0.2	)	$	—		$	(0.5	)	$	—
Spire Alabama
Service cost – benefits earned during the period	$	0.1		$	0.1		$	0.3		$	0.3
Interest cost on accumulated postretirement benefit obligation		0.6			0.5			1.1			0.9
Expected return on plan assets		(1.3	)		(1.3	)		(2.6	)		(2.5	)
Amortization of prior service credit		—			(0.1	)		(0.1	)		(0.2	)
Amortization of actuarial gain		(0.1	)		(0.2	)		(0.1	)		(0.3	)
Subtotal		(0.7	)		(1.0	)		(1.4	)		(1.8	)
Regulatory adjustment		(0.5	)		(0.4	)		(0.9	)		(0.9	)
Net postretirement benefit income	$	(1.2	)	$	(1.4	)	$	(2.3	)	$	(2.7	)