Discontinued Operations and Held-For-Sale Businesses (Schedule of Disposal Groups, Including Discontinued Operations) (Details) - USD ($)			1 Months Ended	3 Months Ended									6 Months Ended	12 Months Ended
		Oct. 31, 2016	Jun. 30, 2016	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Dec. 31, 2017		Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Allowance for Doubtful Accounts									$ 94,000,000							$ 94,000,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations														$ 164,000,000		529,000,000	$ (125,000,000)
Disposal Group, Including Discontinued Operation, Revenue														3,320,000,000		4,036,000,000	4,430,000,000
Income tax expense														21,000,000		(229,000,000)	53,000,000
Income (loss) from operations of discontinued businesses, after income tax														(18,000,000)		151,000,000	80,000,000
Net loss from disposal and impairments of discontinued businesses, after income tax														(611,000,000)		(1,119,000,000)	0
Disposal Group, Including Discontinued Operation, Assets	[1]			$ 2,034,000,000					4,936,000,000					2,034,000,000		4,936,000,000
Disposal Group, Including Discontinued Operation, Liabilities	[1]			1,033,000,000					4,249,000,000					1,033,000,000		4,249,000,000
Disposal Group, Including Discontinued Operation, Costs of Goods Sold														(3,151,000,000)		(3,954,000,000)	(4,227,000,000)
Impairment Expense Pre Tax Total				(277,000,000)		$ (2,000,000)	$ (90,000,000)	$ (168,000,000)	(623,000,000)	$ (79,000,000)	$ (235,000,000)	$ (159,000,000)
Disposal Group, Including Discontinued Operation, Other Expense														(166,000,000)		(160,000,000)	(70,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax														(608,000,000)		(1,463,000,000)	133,000,000
Discontinued Operation, Tax Effect of Discontinued Operation														21,000,000		(495,000,000)	53,000,000
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent														(654,000,000)		(1,110,000,000)	(12,000,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations														(288,000,000)		(368,000,000)	(65,000,000)
Asset Impairment Charges														537,000,000		1,098,000,000	602,000,000
Other Asset Impairment Charges														537,000,000		1,096,000,000	285,000,000
Eletropaulo Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents				0					61,000,000					0		61,000,000
Disposal Group, Including Discontinued Operation, Prepaid and Other Assets				0					268,000,000					0		268,000,000
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net				0					745,000,000					0		745,000,000
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment				0					2,504,000,000					0		2,504,000,000
Disposal Group, Including Discontinued Operations, Investments in and Advances to Affiliates				86,000,000	[2]				0					86,000,000	[2]	0
Disposal Group, Including Discontinued Operation, Deferred Tax Assets				0					554,000,000					0		554,000,000
Disposal Group, Including Discontinued Operation, Other Assets				0					305,000,000					0		305,000,000
Disposal Group, Including Discontinued Operation, Accounts Payable				0					418,000,000					0		418,000,000
Disposal Group, Including Discontinued Operation, Accrued Liabilities				0					954,000,000					0		954,000,000
Non Recourse Debt Held For Sale Or Discontinued Operations				0					1,009,000,000					0		1,009,000,000
Disposal Group, Including Discontinued Operation, Other Liabilities				0					31,000,000					0		31,000,000
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax														(633,000,000)		(192,000,000)	73,000,000
Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss from disposal and impairments of discontinued businesses, after income tax		$ (737,000,000)	$ (382,000,000)													(1,119,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax																(1,413,000,000)	$ (32,000,000)
Discontinued Operations [Member] | Eletropaulo Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets				86,000,000					4,936,000,000					86,000,000		4,936,000,000
Disposal Group, Including Discontinued Operation, Liabilities				0					4,249,000,000					0		4,249,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets				1,948,000,000	[3]				0					1,948,000,000	[3]	0
Disposal Group, Including Discontinued Operation, Liabilities				$ 1,033,000,000	[3]				$ 0					$ 1,033,000,000	[3]	$ 0
Discontinued Operations, Held-for-sale [Member] | Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other Asset Impairment Charges	[4]												$ 783,000,000

[1] Amounts at December 31, 2016 are classified as both current and long-term on the Consolidated Balance Sheet.

[2] Represents the Company's 17% ownership interest in Eletropaulo

[3] Masinloc, Eletrica Santiago, and the DPL peaker assets were classified as held-for-sale as of December 31, 2017. See Note 22—Held-for-Sale Businesses and Dispositions for further information.

[4] See Note 19—Asset Impairment Expense for further information.