Stock Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Jan. 31, 2019	Mar. 31, 2019
Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted (in shares)		693,161
Weighted-average grant-date fair value of options granted (in dollars per share)		$ 8.32
Stock options outstanding		3,210,237
Weighted-average exercise price of stock options outstanding (in dollars per share)		$ 78.25
Intrinsic value in the money stock options		$ 55.8
Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards under Entergy's plans, years		3 years
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	355,537
Restricted stock awards granted value (in dollars per share)	$ 89.19
Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards under Entergy's plans, years		3 years
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	180,824
Percent of performance measure based on relative total shareholder return	8000.00%	8000.00%
Percent of performance measure based on cumulative adjusted EPS metric	2000.00%	2000.00%
Long Term Incentive Plan [Member] \| Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member] \| Performance measure based on relative total shareholder return [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
LTIP awards granted value (in dollars per share)	$ 102.07
Long Term Incentive Plan [Member] \| Equity Ownership And Long Term Cash Incentive Plan Two Thousand Fifteen [Member] \| Performance measure based on cumulative adjusted earnings per share metric [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
LTIP awards granted value (in dollars per share)	$ 89.19

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value of LTIP sotck awards on grant date

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Percent of performance measure based on cumulative adjusted earnings per share metric

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

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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.

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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).

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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).

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

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

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

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