Equity.

No definition available.

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- Definition

The number of stock options not included in the calculation of diluted common shares outstanding due to their antidilutive effect.

+ References

No definition available.

+ Details

Name:	etr_StockOptionsExcludedFromDilutedCommonSharesOutstandingCalculation
Namespace Prefix:	etr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after tax, of accumulated gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

+ Details

Name:	us-gaap_AccumulatedOtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionAfterTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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Period Type:

Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Apr. 08, 2020	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2019
Equity [Abstract]
Stock Options Excluded From Diluted Common Shares Outstanding Calculation		500,000	700,000
Shares, Issued		1,011,970
Common stock dividend (in dollars per share)		$ 0.93	$ 0.91
Accumulated Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, after Tax				$ 6,806
Subsequent Event [Member]
Equity [Abstract]
Common stock dividend (in dollars per share)	$ 0.93