Business Segment Information Business Segment Information (Restructuring Costs) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Employee Retention and Severances Expenses and Other Benefits-Related Costs [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	$ 21
Entergy Wholesale Commodities [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	21	$ 34
Restructuring Reserve	164	227	$ 143	$ 193
Entergy Wholesale Commodities [Member] | Employee Retention and Severances Expenses and Other Benefits-Related Costs [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	21	34
Restructuring Reserve	150	213	129	179
Entergy Wholesale Commodities [Member] | Economic Development Costs [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	0	0
Restructuring Reserve	$ 14	$ 14	$ 14	$ 14