v3.19.3
Divestitures (Details)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
Mar. 31, 2018
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
Jul. 10, 2019
MW
Business Acquisition [Line Items]            
Dividends paid(2) $ (401)   $ (20)      
Impairment losses 0 $ 0   $ 55 $ 0  
Garrison Energy Center and RockGen Energy LLC [Member]            
Business Acquisition [Line Items]            
Ownership percentage of acquiree           100.00%
Proceeds from Sale of Productive Assets 360          
Garrison Energy Center LLC [Member]            
Business Acquisition [Line Items]            
Power generation capacity | MW           309
RockGen Energy LLC [Member]            
Business Acquisition [Line Items]            
Power generation capacity | MW           503
Dividend Paid [Member]            
Business Acquisition [Line Items]            
Dividends paid(2) $ 400          
Commodity Contract [Member]            
Business Acquisition [Line Items]            
Proceeds from Hedge, Financing Activities       $ 52