Condensed Consolidated Statements of Comprehensive Income (Unaudited) - GAS (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Changes in fair value, tax	$ 2	$ 1	$ (5)	$ (4)
Qualifying hedges, reclassification adjustment, tax	8	10	32	27
SOUTHERN Co GAS
Changes in fair value, tax	8	8	16	11
Qualifying hedges, reclassification adjustment, tax	$ (2)	$ 0	$ (7)	$ 1

Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e640-108580

Name:	us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration