Reduction in decommissioning liability.

No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2611-110228

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Asset Retirement Obligations (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017	Sep. 30, 2017
Decommissioning Fund Investments			$ 6,920,164			$ 6,920,164	$ 6,404,030
Asset Retirement Obligation			6,923,400			6,923,400	6,159,200	$ 6,185,800
Entergy Louisiana [Member]
Asset Retirement Obligation, Liabilities Incurred	$ 147,500				$ 85,400
Decommissioning Fund Investments			1,284,996			1,284,996	1,563,812
Asset Retirement Obligation			1,280,300			1,280,300	1,497,300	1,140,500
System Energy [Member]
Decommissioning Fund Investments			869,543			869,543	1,054,098
Asset Retirement Obligation			896,000			896,000	931,700	861,700
Entergy Arkansas [Member]
Asset Retirement Obligation, Liabilities Incurred		$ 126,200
Decommissioning Fund Investments			912,049			912,049	1,101,283
Asset Retirement Obligation			1,048,400			1,048,400	1,242,600	981,200
Entergy Mississippi [Member]
Asset Retirement Obligation			9,200			9,200	$ 9,700	$ 9,200
Vermont Yankee [Member] \| Entergy Wholesale Commodities [Member]
Asset Retirement Obligation, Liabilities Incurred			293,000
Impairment of Long-Lived Assets to be Disposed of			$ 165,000
Pilgrim [Member] \| Entergy Wholesale Commodities [Member]
Asset Retirement Obligation, Liabilities Incurred				$ 117,500
Palisades [Member] \| Entergy Wholesale Commodities [Member]
Reduction in decommissioning liability									$ 68,700
Coal Combustion Residuals [Member] \| Entergy Wholesale Commodities [Member]
Asset Retirement Obligation, Liabilities Incurred						100
Coal Combustion Residuals [Member] \| Entergy Arkansas [Member]
Asset Retirement Obligation, Liabilities Incurred						8,900
Coal Combustion Residuals [Member] \| Entergy Mississippi [Member]
Asset Retirement Obligation, Liabilities Incurred						$ 500