Reportable Segments Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
DD&A	$ (2,297)	$ (2,261)	$ (2,209)
Amortization of excess cost of equity investments	(95)	(61)	(59)
General and administrative and corporate charges	(601)	(688)	(703)
Interest, net	(1,917)	(1,832)	(1,806)
Income tax expense	(587)	(1,938)	(917)
Net Income	1,919	223	721
Total segment EBDA
Segment Reporting Information [Line Items]
Segment EBDA(d)	7,403	6,975	6,364
Operating Segments \| Natural Gas Pipelines
Segment Reporting Information [Line Items]
Segment EBDA(d)	3,580	3,487	3,211
DD&A	(1,058)	(1,011)	(1,041)
Operating Segments \| Products Pipelines
Segment Reporting Information [Line Items]
Segment EBDA(d)	1,173	1,231	1,067
DD&A	(228)	(216)	(221)
Operating Segments \| Terminals
Segment Reporting Information [Line Items]
Segment EBDA(d)	1,171	1,224	1,078
DD&A	(484)	(472)	(435)
Operating Segments \| CO2
Segment Reporting Information [Line Items]
Segment EBDA(d)	759	847	827
DD&A	(473)	(493)	(446)
Operating Segments \| Kinder Morgan Canada
Segment Reporting Information [Line Items]
Segment EBDA(d)	720	186	181
DD&A	(29)	(46)	(44)
Corporate, Non-Segment
Segment Reporting Information [Line Items]
DD&A	(25)	(23)	(22)
General and administrative and corporate charges	$ (588)	$ (660)	$ (652)

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Unallocable Interest Expense Net Of Interest Income

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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