Asset Retirement Obligation Rate Recovery related to Trojan Plant

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- Definition

Damages sought in USDOE claim

+ References

No definition available.

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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

Amount of asset retirement obligations incurred during the period.

+ References

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- Definition

Net Increase or Decrease in the asset retirement obligation during the period.

+ References

+ Details

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- Definition

Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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- Definition

Description of the significant increases or decreases in the carrying amount of the asset retirement obligation during the period, such as changes in significant assumptions used to calculate the carrying amount of the asset retirement obligation.

+ References

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- Definition

Amount of damages awarded to the plaintiff in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Definition

The cash inflow from the sale of assets held in a decommissioning trust fund.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

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Asset Retirement Obligations (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Asset Retirement Obligation, Revision of Estimate	$ 9			$ 30	$ (2)	$ 0
Asset Retirement Obligation, Accretion Expense				7	6	6
Asset Retirement Obligation, Liabilities Incurred	$ 4	$ 7		2	15	4
Loss Contingency, Damages Awarded, Value			$ 70	9
Damages sought in USDOE claim				112
Asset Retirement Obligation Rate Recovery related to Trojan Plant				4
Proceeds from Decommissioning Trust Fund Assets				50
Asset Retirement Obligation, Period Increase (Decrease)				$ 33
Asset Retirement Obligations, Significant Changes				17
Jointly Owned Electricity Generation Plant [Member]
Loss Contingency, Damages Awarded, Value			$ 6		$ 6	$ 44
Utility Plant [Domain]
Asset Retirement Obligation, Revision of Estimate				$ 30
Asset Retirement Obligation, Accretion Expense				4
Asset Retirement Obligation, Liabilities Incurred				$ 1