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, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
DD&A	$ (2,261)	$ (2,209)	$ (2,309)
Amortization of excess cost of equity investments	(61)	(59)	(51)
General and administrative and corporate charges	(673)	(669)	(690)
Interest, net	(1,832)	(1,806)	(2,051)
Income tax expense	(1,938)	(917)	(564)
Net Income	223	721	208
Total segment EBDA
Segment Reporting Information [Line Items]
Segment EBDA(d)	6,975	6,364	5,891
Operating Segments \| Natural Gas Pipelines
Segment Reporting Information [Line Items]
Segment EBDA(d)	3,487	3,211	3,067
DD&A	(1,011)	(1,041)	(1,046)
Operating Segments \| CO2
Segment Reporting Information [Line Items]
Segment EBDA(d)	847	827	658
DD&A	(493)	(446)	(556)
Operating Segments \| Terminals
Segment Reporting Information [Line Items]
Segment EBDA(d)	1,224	1,078	878
DD&A	(472)	(435)	(433)
Operating Segments \| Products Pipelines
Segment Reporting Information [Line Items]
Segment EBDA(d)	1,231	1,067	1,106
DD&A	(216)	(221)	(206)
Operating Segments \| Kinder Morgan Canada
Segment Reporting Information [Line Items]
Segment EBDA(d)	186	181	182
DD&A	(46)	(44)	(46)
Corporate, Non-Segment
Segment Reporting Information [Line Items]
DD&A	(23)	(22)	(22)
General and administrative and corporate charges	$ (660)	$ (652)	$ (708)

Segment Earnings Before Depreciation Depletion And Amortization

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Unallocable Interest Expense Net Of Interest Income

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of expense charged against earnings to allocate the cost of tangible and intangible assets over their remaining economic lives, classified as other.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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