Summary Of Significant Accounting Policies (Schedule Of Subsidiaries' Investment And Accumulated Depreciation In Generating Stations) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 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	839
Ownership	31.50%
Investment	$ 134
Accumulated Depreciation	$ 103
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	$ 34
Accumulated Depreciation	$ 27
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	$ 16
Accumulated Depreciation	$ 12
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	1,635
Ownership	57.00%
Investment	$ 521
Accumulated Depreciation	$ 365
Ouachita Common Facilities [Member] | Entergy Arkansas [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Total Megawatt Capability | MW	493
Ownership	66.67%
Investment	$ 172
Accumulated Depreciation	$ 148
Ouachita Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Total Megawatt Capability | MW	248
Ownership	33.33%
Investment	$ 90
Accumulated Depreciation	$ 75
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	550
Ownership	40.25%
Investment	$ 277
Accumulated Depreciation	$ 189
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	550
Ownership	29.75%
Investment	$ 198
Accumulated Depreciation	$ 113
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	550
Ownership	10.90%
Investment	$ 112
Accumulated Depreciation	$ 60
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	18.65%
Investment	$ 14
Accumulated Depreciation	$ 6
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	13.79%
Investment	$ 6
Accumulated Depreciation	$ 2
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	5.05%
Investment	$ 2
Accumulated Depreciation	$ 1
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	588
Ownership	24.15%
Investment	$ 150
Accumulated Depreciation	$ 113
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	588
Ownership	17.85%
Investment	$ 113
Accumulated Depreciation	$ 74
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
Accumulated Depreciation	$ 2
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	$ 3
Accumulated Depreciation	$ 1
Acadia Common Facilities [Member] | Entergy Louisiana [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant Fuel Type	Gas
Total Megawatt Capability | MW	557
Ownership	50.00%
Investment	$ 19
Accumulated Depreciation	$ 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	1,681
Ownership	25.00%
Investment	$ 257
Accumulated Depreciation	$ 155
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	1,401
Ownership	90.00%
Investment	$ 4,917
Accumulated Depreciation	$ 3,063
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	$ 71
Accumulated Depreciation	$ 49
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	$ 1
Accumulated Depreciation	$ 0
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
Accumulated Depreciation	$ 0
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	$ 25
Accumulated Depreciation	$ 1
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	$ 50
Accumulated Depreciation	$ 1
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	$ 25
Accumulated Depreciation	$ 1
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%