Acquisitions And Divestitures (Schedule of EnLink's Acquisition Activity) (Details) - USD ($) $ in Millions	Oct. 31, 2015	Mar. 31, 2015	Jan. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	[1]	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill				$ 2,383	$ 2,383		$ 3,337
EnLink [Member] | Permian Basin Midstream Assets [Member]
Business Acquisition [Line Items]
Cash payment to acquire interest		$ 240	$ 108
Common units value		360
PP&E		302	30
Goodwill		18	30
Intangibles		281	43
Current assets			$ 5
Current liabilities		$ (1)
EnLink [Member] | Delaware Basin Midstream Assets [Member]
Business Acquisition [Line Items]
Cash payment to acquire interest	$ 141
PP&E	36
Goodwill	11
Intangibles	99
Current liabilities	$ (5)

[1] Prior year amounts have been recast due to change in accounting principle. See Note 2 in “Item 8. Financial Statements and Supplementary Data” of this report.