Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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Income Taxes (Details) - USD ($) $ in Billions	6 Months Ended
Income Taxes (Details) - USD ($) $ in Billions	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
ITC and PTC carryforwards
Income Tax Contingency [Line Items]
Deferred tax assets	$ 1.3		$ 1.4
GEORGIA POWER CO
Income Tax Contingency [Line Items]
Effective tax (benefit) rate	(6.90%)	4.00%
SOUTHERN POWER CO
Income Tax Contingency [Line Items]
Effective tax (benefit) rate	(12.80%)	10.50%