v3.19.1

Variable Interest Entities and Unconsolidated Investments in Power Plants (Income from Unconsolidated Investments 10-Q) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
(Income) from unconsolidated subsidiaries	$ (6)	$ (6)
Greenfield [Member]
(Income) from unconsolidated subsidiaries	(2)	(2)
Whitby [Member]
(Income) from unconsolidated subsidiaries	$ (4)	$ (4)

X

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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-Topic 230
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Details

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X

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