Increase in decommissioning liability.

No definition available.

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- Definition

Reduction in decommissioning liability.

+ References

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

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
	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Decommissioning Fund Investments	$ 6,920,164			$ 7,211,993
Asset Retirement Obligation	6,923,400			6,185,800			$ 6,706,800
Entergy Louisiana [Member]
Increase in decommissioning liability			$ 85,400
Decommissioning Fund Investments	1,284,996			1,312,073
Asset Retirement Obligation	1,280,300			1,140,500			1,082,700
System Energy [Member]
Reduction in decommissioning liability						$ 35,900
Decommissioning Fund Investments	869,543			905,686
Asset Retirement Obligation	896,000			861,700			854,200
Entergy Wholesale Commodities [Member]
Asset Retirement Obligation	3,679,000			3,183,300			3,827,400
Entergy Arkansas [Member]
Decommissioning Fund Investments	912,049			944,890
Asset Retirement Obligation	1,048,400			981,200			924,400
Entergy Mississippi [Member]
Asset Retirement Obligation	9,200			$ 9,200			8,700
Vermont Yankee [Member] \| Entergy Wholesale Commodities [Member]
Increase in decommissioning liability	293,000
Impairment of Long-Lived Assets to be Disposed of	165,000
Pilgrim [Member] \| Entergy Wholesale Commodities [Member]
Increase in decommissioning liability		$ 117,500
Palisades [Member] \| Entergy Wholesale Commodities [Member]
Reduction in decommissioning liability					$ 68,700
Increase in decommissioning liability							129,000
Indian Point Energy Center Units [Member] \| Entergy Wholesale Commodities [Member]
Increase in decommissioning liability							$ 392,000
Coal Combustion Residuals [Member] \| Entergy Wholesale Commodities [Member]
Increase in decommissioning liability	100
Coal Combustion Residuals [Member] \| Entergy Arkansas [Member]
Increase in decommissioning liability	8,900
Coal Combustion Residuals [Member] \| Entergy Mississippi [Member]
Increase in decommissioning liability	$ 500