Acquisitions and Discontinued Operations Acquisitions Pro Forma (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue					$ 6,549		$ 6,640
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax					1,396		844
Income (Loss) from Discontinued Operations	(131)	[1]	55	[1]	(682)	[1]	145	[1]
Business Acquisition, Pro Forma Net Income (Loss)					714		989
Pro forma income attributable to noncontrolling interests					(12)		(8)
Pro forma income attributable to Kinder Morgan Energy Partners L.P.					$ 702		$ 981
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax, Per Share, Diluted					$ 0.82		$ (0.19)
Pro forma income from discontinued operations per unit					(1.89)		0.43
Business Acquisition, Pro Forma Earnings Per Share, Diluted					$ (1.07)		$ 0.24

[1] Represents amounts attributable to our FTC Natural Gas Pipelines disposal group.