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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Goodwill and Other Intangibles (Goodwill - Details 1) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2006 USD ($)
Goodwill and Other Intangibles
Goodwill	$ 662	$ 999
Goodwill deductible for U.S. income tax purposes	547	620
Goodwill, Impairment Loss		1,500
Texas Genco
Goodwill and Other Intangibles
Goodwill in connection with acquisition			$ 1,700
Texas [Member]
Goodwill and Other Intangibles
Goodwill, Impairment Loss	$ 337	$ 1,400
Reporting Unit, Percentage of Carrying Amount in Excess of Fair Value	0.43	0.76
Home Solar [Member]
Goodwill and Other Intangibles
Goodwill, Impairment Loss		$ 125
Goal Zero [Member]
Goodwill and Other Intangibles
Goodwill, Impairment Loss		$ 36
EME [Member]
Goodwill and Other Intangibles
Goodwill	$ 276
Retail [Member]
Goodwill and Other Intangibles
Goodwill	341
Other [Member]
Goodwill and Other Intangibles
Goodwill	45
Texas [Member]
Goodwill and Other Intangibles
Goodwill	$ 0