Asset Retirement Obligation Period Increase Decrease.

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- Definition

Asset Retirement Obligations.

+ References

No definition available.

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- Definition

Asset Retirement Obligations, Transfers

+ References

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- Definition

Public Utilities, Plant Ownership Percentage

+ References

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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://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Asset Retirement Obligation
-URI http://asc.fasb.org/extlink&oid=6505190

+ Details

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ 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 (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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- Definition

Carrying amount of an asset that is legally restricted for purposes of settling an asset retirement obligation.

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Asset Retirement Obligations (Details) - USD ($) $ in Millions		9 Months Ended
	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2015
Asset Retirement Obligations [Line Items]
Fair value of decommissioning trust assets		$ 2,502	$ 2,282
Changes to the asset retirement obligations
Beginning Balance		1,410
Liabilities settled		(25)
Liabilities incurred		4
Accretion		70
Ending Balance		1,459
FES
Asset Retirement Obligations [Line Items]
Fair value of decommissioning trust assets		1,542	$ 1,327
Changes to the asset retirement obligations
Beginning Balance		831
Liabilities settled		(17)
Liabilities incurred		32
Accretion		41
Ending Balance		887
FES \| Beaver Valley, Davis-Besse and Perry Power Plants
Changes to the asset retirement obligations
Ending Balance		701
NG \| Perry Power Plant Unit 1
Changes to the asset retirement obligations
ARO transferred		$ 28
Ownership percentage	100.00%