Discontinued Operations And Held-For-Sale Businesses (Details) (USD $)	3 Months Ended			6 Months Ended					7 Months Ended	0 Months Ended		0 Months Ended		1 Months Ended	3 Months Ended	1 Months Ended
	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013 Sonel [Member]	Sep. 30, 2013 Kribi [Member]	Sep. 30, 2013 Dibamba [Member]	Mar. 31, 2014 Cameroon [Member]	Feb. 24, 2014 Saurashtra [Member]	Oct. 30, 2013 Saurashtra [Member] MW	Jan. 30, 2014 US Wind Projects [Member]	Nov. 30, 2013 US Wind Projects [Member] project MW	Jun. 30, 2014 Cameroon [Member] business	Jun. 30, 2014 Cameroon [Member] business	Nov. 30, 2013 Armenia Mountain [Member] MW	Jun. 30, 2014 Noncurrent Asset [Member] Cameroon [Member]
Discontinued Operations Income Loss
Revenue	$ 104,000,000	$ 164,000,000	[1]	$ 233,000,000	$ 426,000,000
Income from operations of discontinued businesses, before income tax	15,000,000	4,000,000	[1]	49,000,000	6,000,000
Income tax expense	(8,000,000)	(7,000,000)	[1]	(22,000,000)	(5,000,000)
Income (loss) from operations of discontinued businesses, after income tax	7,000,000	(3,000,000)	[1]	27,000,000	1,000,000
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Sale of ownership in subsidiary percent						56.00%	56.00%	56.00%					100.00%
Number of Equity Interests Sold														3	3
Equity Method Investment, Net Sales Proceeds														202,000,000			40,000,000
Disposal Group, Including Discontinued Operation, Non-contingent Consideration, Fair Value, Amount to be Received																	40,000,000
Letter of Credit Related to Sale Agreement														40,000,000	40,000,000
Net proceeds received from sale of businesses										8,000,000		27,000,000		162,000,000
Impairment expenses				273,000,000	48,000,000				101,000,000
Carrying amount									435,000,000
Fair value less costs to sell									334,000,000
Net (loss) income from disposal and impairments of discontinued businesses, after income tax	(13,000,000)	3,000,000	[1]	(56,000,000)	(33,000,000)										(7,000,000)
Generation capacity mega watts											39		234			101
Number of wind projects													3
Buyer option to purchase ownership percent																100.00%
Buyer option to purchase ownership interest, sales price																75,000,000
Deferred proceeds from divestiture of businesses												$ 3,000,000

[1] Includes the results of operations of our Ukraine utility businesses, which were sold in April 2013.