XML 120 R91.htm IDEA: XBRL DOCUMENT v3.21.2
Acquisitions and Dispositions - Southern Company Gas Narrative (Details)
$ in Millions
3 Months Ended 9 Months Ended
Jul. 01, 2021
USD ($)
Sep. 30, 2021
USD ($)
Sep. 30, 2021
USD ($)
Sep. 30, 2021
USD ($)
Sep. 30, 2020
USD ($)
Feb. 28, 2022
USD ($)
Apr. 22, 2021
USD ($)
Jun. 30, 2020
payment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                
Gain on sale       $ 171 $ 36      
SOUTHERN Co GAS                
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                
Gain on sale       127 $ (2)      
Deferred tax expense, increase from change in appointment rate     $ 85 85        
SOUTHERN Co GAS | Sequent | Disposal Group, Disposed of by Sale                
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                
Sale price $ 159              
Gain on sale 121              
Gain on sale, net of tax $ 93              
Deferred tax expense, increase from change in appointment rate   $ 85            
Guarantor obligations, current carrying value   36 36 36        
Guarantor obligations   $ 1,000 $ 1,000 $ 1,000        
SOUTHERN Co GAS | Pivotal LNG | Disposal Group, Disposed of by Sale                
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                
Number of contingent milestone payments | payment               2
Contingent milestone payment, amount             $ 5  
SOUTHERN Co GAS | Scenario, Forecast | Pivotal LNG | Disposal Group, Disposed of by Sale                
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                
Contingent milestone payment, amount           $ 5