Asset Retirement Obligations (Fair Values Of Decommissioning Trust Funds And Related Asset Retirement Obligation Regulatory Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
ANO 1 and ANO 2 [Member]
Asset Retirement Obligations [Line Items]
Decommissioning Trust Fair Values	$ 944.9	$ 834.7
Regulatory Asset	337.9	316.3
River Bend [Member]
Asset Retirement Obligations [Line Items]
Decommissioning Trust Fair Values	818.2	712.8
Regulatory Liabilities	30.6	(28.4)
Waterford 3 [Member]
Asset Retirement Obligations [Line Items]
Decommissioning Trust Fair Values	493.9	427.9
Regulatory Asset	188.9	172.8
Grand Gulf [Member]
Asset Retirement Obligations [Line Items]
Decommissioning Trust Fair Values	905.7	780.5
Regulatory Asset	169.1	142.5
Entergy Wholesale Commodities [Member]
Asset Retirement Obligations [Line Items]
Decommissioning Trust Fair Values	4,049.3	2,968.0
Regulatory Asset	$ 0.0	$ 0.0

Asset Retirement Obligations [Line Items]

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- Definition

The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

+ Details

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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