XML 91 R66.htm IDEA: XBRL DOCUMENT v3.26.1

Retirement Benefits (Tables)

3 Months Ended

Mar. 31, 2026

Retirement Benefits [Abstract]

Schedule of Pension Plans and Postretirement Plans

Components of the net periodic benefit costs for the three months ended March 31, 2026 and 2025 are presented in the following tables.

			Southern Company						Alabama Power						Georgia Power						Mississippi Power						Southern Power						Southern Company Gas
			(in millions)
Three Months Ended March 31, 2026
Pension Plans
Service cost			$	69					$	15					$	17					$	3					$	2					$	7
Interest cost			162						38						47						7						2						11
Expected return on plan assets			(322)						(79)						(99)						(15)						(4)						(21)
Amortization:
Prior service costs			—						—						—						—						—						(1)
Regulatory asset			—						—						—						—						—						3
Net loss			18						5						6						1						—						—
Net periodic pension income			$	(73)					$	(21)					$	(29)					$	(4)					$	—					$	(1)
Postretirement Benefits
Service cost			$	3					$	1					$	1					$	—					$	—					$	—
Interest cost			16						4						6						1						—						2
Expected return on plan assets			(23)						(9)						(8)						(1)						—						(2)
Amortization:
Prior service costs			1						—						—						—						—						—
Net gain			(2)						—						—						—						—						(2)
Net periodic postretirement benefit income			$	(5)					$	(4)					$	(1)					$	—					$	—					$	(2)

			Southern Company						Alabama Power						Georgia Power						Mississippi Power						Southern Power						Southern Company Gas
			(in millions)
Three Months Ended March 31, 2025
Pension Plans
Service cost			$	66					$	15					$	16					$	3					$	1					$	7
Interest cost			166						39						49						7						2						11
Expected return on plan assets			(320)						(78)						(99)						(15)						(4)						(22)
Amortization:
Prior service costs			—						—						—						—						—						(1)
Regulatory asset			—						—						—						—						—						4
Net loss			9						2						4						1						1						—
Net periodic pension income			$	(79)					$	(22)					$	(30)					$	(4)					$	—					$	(1)
Postretirement Benefits
Service cost			$	3					$	1					$	1					$	—					$	—					$	—
Interest cost			17						4						6						1						—						2
Expected return on plan assets			(23)						(9)						(8)						—						—						(2)
Amortization:
Prior service costs			1						—						—						—						—						—
Regulatory asset			—						—						—						—						—						2
Net gain			(3)						—						—						(1)						—						(2)
Net periodic postretirement benefit income			$	(5)					$	(4)					$	(1)					$	—					$	—					$	—

X

- References

No definition available.

+ Details

Name:	us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (h)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration