Stock Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
Jan. 25, 2018	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted (in shares)	687,400
Weighted-average grant-date fair value of options granted (in dollars per share)	$ 6.99
Stock options outstanding		4,393,990
Weighted-average exercise price of stock options outstanding (in dollars per share)		$ 74.39
Intrinsic value in the money stock options		$ 19.3
Vesting period of awards under Entergy's plans, years		3 years
Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted value (in dollars per share)	78.08
LTIP awards granted value (in dollars per share)	86.75
LTIP awards granted value based on stock price (in dollars per share)	$ 78.08
Restricted Awards [Member] \| Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	333,850
Long Term Incentive Plan [Member] \| Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term incentive plan awards	182,408

LTIP awards granted value based on stock price

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- Definition

Long Term Incentive Plan Awards

+ References

No definition available.

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- Definition

value of LTIP sotck awards on grant date

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award in the money stock options intrinsic value.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Net number of share options (or share units) granted during the period.

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-Publisher FASB
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-SubTopic 10
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Publisher FASB
-Name Accounting Standards Codification
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