Average coupon rate of debt securities percentage.

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- Definition

Average Duration of Debt Securities in Years

+ References

No definition available.

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- Definition

Average Maturity of Debt Securities, Years

+ References

No definition available.

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- Definition

Decommissioning Trust Funds.

+ References

No definition available.

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- Definition

Percentage Interest in River Bend

+ References

No definition available.

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- 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/presentationRef
-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

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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- Definition

This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
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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 cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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Decommissioning Trust Funds (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jan. 01, 2018
Accumulated Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, after Tax				$ (632,617)
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 2,643,000		$ 2,539,000
Average coupon rate of debt securities	3.26%
Average duration of debt securities, years	6 years 66 days
Average maturity of debt securities, years	10 years 33 days
Proceeds from the dispositions of debt securities	$ 1,091,000	$ 514,000
Gains from dispositions of debt securities, gross	1,000	9,000
Losses from dispositions of debt securities, gross	7,000	5,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax			(17,000)
Equity Securities [Member]
Decommissioning Trust Funds [Abstract]
Deferred taxes on unrealized gains/(losses) recorded in OCI for non-regulated decommissioning trusts			472,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(64,000)		(1,000)
Debt Securities [Member]
Decommissioning Trust Funds [Abstract]
Deferred taxes on unrealized gains/(losses) recorded in OCI for non-regulated decommissioning trusts	(2,000)		7,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(48,000)		(16,000)
Entergy Arkansas [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 360,000		349,100
Average coupon rate of debt securities	2.67%
Average duration of debt securities, years	5 years 175 days
Average maturity of debt securities, years	6 years 329 days
Proceeds from the dispositions of debt securities	$ 34,900	36,000
Gains from dispositions of debt securities, gross	100	500
Losses from dispositions of debt securities, gross	0	100
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax			(3,000)
Entergy Arkansas [Member] \| Equity Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(8,000)		0
Entergy Arkansas [Member] \| Debt Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(9,700)		(3,000)
Entergy Louisiana [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 519,000		490,000
Average coupon rate of debt securities	3.83%
Average duration of debt securities, years	6 years 18 days
Average maturity of debt securities, years	11 years 310 days
Proceeds from the dispositions of debt securities	$ 125,500	40,600
Gains from dispositions of debt securities, gross	500	0
Losses from dispositions of debt securities, gross	$ 800	200
Percentage Interest in River Bend	30.00%
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax			(3,600)
Entergy Louisiana [Member] \| Equity Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ (10,800)		0
Entergy Louisiana [Member] \| Debt Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(8,400)		(3,600)
System Energy [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 330,000		327,500
Average coupon rate of debt securities	2.72%
Average duration of debt securities, years	6 years 139 days
Average maturity of debt securities, years	9 years 141 days
Proceeds from the dispositions of debt securities	$ 54,200	75,800
Gains from dispositions of debt securities, gross	100	100
Losses from dispositions of debt securities, gross	600	$ 700
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax			(1,200)
System Energy [Member] \| Equity Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(7,800)		0
System Energy [Member] \| Debt Securities [Member]
Decommissioning Trust Funds [Abstract]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(5,800)		(1,200)
Indian Point 3 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	789,000		798,000
Indian Point 1 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	485,000		491,000
Indian Point 2 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	614,000		621,000
Palisades [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	453,000		458,000
Pilgrim [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	1,048,000		1,068,000
Vermont Yankee [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	$ 591,000		$ 613,000