Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Income Tax [Line Items]
Deferred tax assets, valuation allowance	$ 808	$ 967
Valuation allowance against U.S. deferred tax assets, percent		100.00%
General Partner And EnLink [Member]
Income Tax [Line Items]
Goodwill impairments	$ 873