Condensed Consolidated Statements of Comprehensive Income (Unaudited) - SPC (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Changes in fair value, tax	$ 8	$ (10)
Qualifying hedges, reclassification adjustment, tax	6	18
Reclassification adjustment for amounts included in net income, tax	1	1
Southern Power
Changes in fair value, tax	(6)	(11)
Qualifying hedges, reclassification adjustment, tax	7	15
Reclassification adjustment for amounts included in net income, tax	$ 0	$ 0

Amount, before reclassification, of tax expense (benefit) for gain (loss) from 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 http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580

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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.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
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