Summary Of Significant Accounting Policies (Schedule Of Subsidiaries' Investment And Accumulated Depreciation In Generating Stations) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) MW
Independence Unit 1 [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	826
Ownership	31.50%
Investment	$ 142.0
Accumulated Depreciation	$ 104.0
Independence Common Facilities [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	15.75%
Investment	$ 35.0
Accumulated Depreciation	$ 29.0
Independence Common Facilities [Member] | Entergy Wholesale Commodities [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	7.18%
Investment	$ 17.0
Accumulated Depreciation	$ 13.0
White Bluff Units 1 And 2 [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	1,638
Ownership	57.00%
Investment	$ 555.0
Accumulated Depreciation	$ 380.0
Ouachita Common Facilities [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	66.67%
Investment	$ 173.0
Accumulated Depreciation	$ 153.0
Ouachita Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	33.33%
Investment	$ 90.0
Accumulated Depreciation	$ 77.0
Roy S. Nelson Unit 6 [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	525
Ownership	40.25%
Investment	$ 286.0
Accumulated Depreciation	$ 207.0
Roy S. Nelson Unit 6 [Member] | Entergy Texas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	525
Ownership	29.75%
Investment	$ 204.0
Accumulated Depreciation	$ 120.0
Roy S. Nelson Unit 6 [Member] | Entergy Wholesale Commodities [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	525
Ownership	10.90%
Investment	$ 115.0
Accumulated Depreciation	$ 66.0
Roy S. Nelson Unit 6 Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	19.95%
Investment	$ 20.0
Accumulated Depreciation	$ 9.0
Roy S. Nelson Unit 6 Common Facilities [Member] | Entergy Texas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	14.75%
Investment	$ 7.0
Accumulated Depreciation	$ 3.0
Roy S. Nelson Unit 6 Common Facilities [Member] | Entergy Wholesale Commodities [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	5.40%
Investment	$ 3.0
Accumulated Depreciation	$ 1.0
Big Cajun 2 Unit 3 [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	576
Ownership	24.15%
Investment	$ 151.0
Accumulated Depreciation	$ 124.0
Big Cajun 2 Unit 3 [Member] | Entergy Texas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	576
Ownership	17.85%
Investment	$ 113.0
Accumulated Depreciation	$ 80.0
Big Cajun 2 Unit 3 Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	8.05%
Investment	$ 5.0
Accumulated Depreciation	$ 2.0
Big Cajun 2 Unit 3 Common Facilities [Member] | Entergy Texas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Ownership	5.95%
Investment	$ 4.0
Accumulated Depreciation	$ 1.0
Acadia Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	50.00%
Investment	$ 20.0
Accumulated Depreciation	$ 1.0
Independence Units 1 And 2 And Common Facilities [Member] | Entergy Mississippi [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	1,668
Ownership	25.00%
Investment	$ 271.0
Accumulated Depreciation	$ 163.0
Grand Gulf Unit 1 [Member] | System Energy [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Nuclear
Total Megawatt Capability | MW	1,393
Ownership	90.00%
Investment	$ 5,071.0
Accumulated Depreciation	$ 3,285.0
Independence Unit 2 [Member] | Entergy Wholesale Commodities [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Coal
Total Megawatt Capability | MW	842
Ownership	14.37%
Investment	$ 74.0
Accumulated Depreciation	$ 53.0
Ouachita Units 1 and 2 [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Ownership	100.00%
Ouachita Unit 3 [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Ownership	100.00%
Union Units 1 and 2 Common Facilities [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	50.00%
Investment	$ 0.4
Accumulated Depreciation	$ 0.1
Union Units 1 and 2 Common Facilities [Member] | Entergy New Orleans [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	50.00%
Investment	$ 1.0
Accumulated Depreciation	$ 0.1
Union Common Facilities [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	25.00%
Investment	$ 29.0
Accumulated Depreciation	$ 6.0
Union Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	50.00%
Investment	$ 57.0
Accumulated Depreciation	$ 6.0
Union Common Facilities [Member] | Entergy New Orleans [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Ownership	25.00%
Investment	$ 29.0
Accumulated Depreciation	$ 6.0
Union Unit 1 [Member] | Entergy New Orleans [Member]
Jointly Owned Utility Plant Interests [Line Items]
Ownership	100.00%
Union Unit 2 [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Ownership	100.00%
Union Units 3 and 4 [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Ownership	100.00%