Pension Plans and Other Postretirement Benefits (Tables)

3 Months Ended

Dec. 31, 2020

Pension Plans

Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]

Net periodic cost

The net periodic pension cost included the following components:

	Three Months Ended December 31,
	2020			2019
Spire
Service cost – benefits earned during the period	$	5.6		$	5.5
Interest cost on projected benefit obligation*		5.2			5.9
Expected return on plan assets*		(8.0	)		(9.2	)
Amortization of prior service credit*		(0.8	)		(0.6	)
Amortization of actuarial loss*		4.0			3.7
Subtotal		6.0			5.3
Regulatory adjustment		9.6			9.6
Net pension cost	$	15.6		$	14.9
Spire Missouri
Service cost – benefits earned during the period	$	3.9		$	3.8
Interest cost on projected benefit obligation*		3.5			4.2
Expected return on plan assets*		(5.6	)		(6.6	)
Amortization of prior service credit*		(0.2	)		—
Amortization of actuarial loss*		2.9			2.9
Subtotal		4.5			4.3
Regulatory adjustment		7.6			7.7
Net pension cost	$	12.1		$	12.0
Spire Alabama
Service cost – benefits earned during the period	$	1.5		$	1.5
Interest cost on projected benefit obligation*		1.2			1.2
Expected return on plan assets*		(1.6	)		(1.7	)
Amortization of prior service credit*		(0.6	)		(0.6	)
Amortization of actuarial loss*		1.1			0.8
Subtotal		1.6			1.2
Regulatory adjustment		1.8			1.7
Net pension cost	$	3.4		$	2.9

* Denotes pension expense line items that are recorded below the operating income line in the income statements, in the line item “Other Income, Net.”

Other Postretirement Plans

Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]

Net periodic cost

Net periodic postretirement benefit costs consisted of the following components:

	Three Months Ended December 31,
	2020			2019
Spire
Service cost – benefits earned during the period	$	1.8		$	1.4
Interest cost on accumulated postretirement benefit obligation*		1.4			1.6
Expected return on plan assets*		(4.0	)		(4.1	)
Amortization of prior service cost (credit)*		0.3			(0.2	)
Amortization of actuarial gain*		(0.4	)		(0.5	)
Subtotal		(0.9	)		(1.8	)
Regulatory adjustment		3.4			4.0
Net postretirement benefit cost	$	2.5		$	2.2
Spire Missouri
Service cost – benefits earned during the period	$	1.6		$	1.3
Interest cost on accumulated postretirement benefit obligation*		1.1			1.2
Expected return on plan assets*		(2.7	)		(2.8	)
Amortization of prior service cost (credit) *		0.2			(0.1	)
Amortization of actuarial gain*		(0.4	)		(0.5	)
Subtotal		(0.2	)		(0.9	)
Regulatory adjustment		3.8			4.4
Net postretirement benefit cost	$	3.6		$	3.5
Spire Alabama
Service cost – benefits earned during the period	$	0.2		$	0.1
Interest cost on accumulated postretirement benefit obligation*		0.3			0.3
Expected return on plan assets*		(1.2	)		(1.2	)
Amortization of prior service cost (credit)*		0.1			(0.1	)
Subtotal		(0.6	)		(0.9	)
Regulatory adjustment		(0.4	)		(0.4	)
Net postretirement benefit income	$	(1.0	)	$	(1.3	)

* Denotes other postretirement expense line items that are recorded below the operating income line in the income statements, in the line item “Other Income, Net.”