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

3 Months Ended

Dec. 31, 2023

Notes Tables

Schedule of Net Benefit Costs [Table Text Block]

	Three Months Ended December 31,
	2023			2022
Spire
Service cost – benefits earned during the period	$	4.0		$	4.1
Interest cost on projected benefit obligation		6.8			6.4
Expected return on plan assets		(6.3	)		(6.4	)
Amortization of prior service credit		(1.1	)		(1.1	)
Amortization of actuarial loss		1.6			1.6
Loss on lump-sum settlements		—			8.6
Subtotal		5.0			13.2
Regulatory adjustment		8.7			1.8
Net pension cost	$	13.7		$	15.0
Spire Missouri
Service cost – benefits earned during the period	$	2.6		$	2.8
Interest cost on projected benefit obligation		4.8			4.5
Expected return on plan assets		(4.3	)		(4.5	)
Amortization of prior service credit		(0.5	)		(0.5	)
Amortization of actuarial loss		1.5			1.5
Subtotal		4.1			3.8
Regulatory adjustment		6.3			8.1
Net pension cost	$	10.4		$	11.9
Spire Alabama
Service cost – benefits earned during the period	$	1.2		$	1.1
Interest cost on projected benefit obligation		1.3			1.3
Expected return on plan assets		(1.2	)		(1.1	)
Amortization of prior service credit		(0.6	)		(0.6	)
Amortization of actuarial loss		0.2			0.1
Loss on lump-sum settlements		—			8.6
Subtotal		0.9			9.4
Regulatory adjustment		2.2			(6.5	)
Net pension cost	$	3.1		$	2.9

	Three Months Ended December 31,
	2023			2022
Spire
Service cost – benefits earned during the period	$	1.1		$	1.2
Interest cost on accumulated postretirement benefit obligation		2.1			2.1
Expected return on plan assets		(4.0	)		(3.9	)
Amortization of prior service cost		0.1			0.1
Amortization of actuarial gain		(1.0	)		(1.0	)
Subtotal		(1.7	)		(1.5	)
Regulatory adjustment		0.2			0.1
Net postretirement benefit income	$	(1.5	)	$	(1.4	)
Spire Missouri
Service cost – benefits earned during the period	$	0.9		$	1.0
Interest cost on accumulated postretirement benefit obligation		1.6			1.6
Expected return on plan assets		(2.7	)		(2.6	)
Amortization of prior service cost		0.2			0.2
Amortization of actuarial gain		(0.9	)		(0.8	)
Subtotal		(0.9	)		(0.6	)
Regulatory adjustment		0.6			0.6
Net postretirement benefit income	$	(0.3	)	$	—
Spire Alabama
Service cost – benefits earned during the period	$	0.2		$	0.2
Interest cost on accumulated postretirement benefit obligation		0.5			0.4
Expected return on plan assets		(1.3	)		(1.2	)
Amortization of prior service credit		(0.1	)		(0.1	)
Amortization of actuarial gain		—			(0.1	)
Subtotal		(0.7	)		(0.8	)
Regulatory adjustment		(0.4	)		(0.5	)
Net postretirement benefit income	$	(1.1	)	$	(1.3	)