Reportable Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Reportable Segments - (Details) [Abstract]
Number of reportable business segments	5		5
Revenues [Abstract]
Revenues from external customers	$ 2,195.1	$ 2,060.0	$ 6,207.2	$ 6,151.1
Intersegment revenues	0.4	0.3	0.9	0.8
Total segment revenues	2,195.5	2,060.3	6,208.1	6,151.9
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	706.6	779.5	2,286.3	2,264.2
Depreciation, depletion and amortization	(253.4)	(224.1)	(704.6)	(674.6)
Amortization of excess cost of investments	(1.8)	(1.4)	(4.9)	(4.3)
General and administrative expenses	(100.5)	(93.6)	(387.1)	(288.1)
Unallocable interest expense, net of interest income	(132.5)	(133.8)	(393.8)	(373.9)
Unallocable income tax expense	(2.1)	(4.2)	(6.8)	(8.4)
Total consolidated net income	216.3	322.4	789.1	914.9
Assets [Abstract]
Assets	22,612.9		22,612.9		21,328.6
Corporate assets	965.4		965.4		532.5
Total consolidated assets	23,578.3		23,578.3		21,861.1
Amount of increase in expense included in Products earnings before DDA relating to rate case liability adjustments	69.3		234.3	158.0
Increase in expense due to one-time special bonus			87.1
Products Pipelines [Member]
Revenues [Abstract]
Revenues from external customers	241.6	227.7	694.6	661.5
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	102.7	167.5	303.9	339.1
Assets [Abstract]
Assets	4,398.3		4,398.3		4,369.1
Natural Gas Pipelines [Member]
Revenues [Abstract]
Revenues from external customers	1,176.4	1,147.6	3,240.1	3,414.0
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	80.8	187.3	484.7	592.9
Assets [Abstract]
Assets	9,711.8		9,711.8		8,809.7
CO2 [Member]
Revenues [Abstract]
Revenues from external customers	372.0	296.0	1,062.8	932.4
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	294.8	221.5	823.2	724.1
Assets [Abstract]
Assets	2,322.1		2,322.1		2,141.2
Terminals [Member]
Revenues [Abstract]
Revenues from external customers	327.7	321.2	979.4	945.3
Intersegment revenues	0.4	0.3	0.9	0.8
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	179.8	159.2	524.5	475.2
Assets [Abstract]
Assets	4,376.6		4,376.6		4,138.6
Kinder Morgan Canada [Member]
Revenues [Abstract]
Revenues from external customers	77.4	67.5	230.3	197.9
Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments [Abstract]
Segment earnings before DDA	48.5	44.0	150.0	132.9
Assets [Abstract]
Assets	$ 1,804.1		$ 1,804.1		$ 1,870.0

The amount of increase in expense included in Products earnings before DDA relating to rate case liability adjustments.

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Increase in expense associated with a one-time special cash bonus payment paid to non-senior management employees; however, Kinder Morgan do not have any obligation, nor does Kinder Morgan expect to pay any amounts related to this expense.

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A segment of an entity for which there is an accounting requirement to report separate financial information on that segment in the entity's financial statements.

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Segment earnings before depreciation, depletion, amortization and amortization of excess cost of equity investments. This item includes earnings from equity investments, allocable interest income, and other, net, less operating expenses, allocable income taxes and other expense (income).

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The amount of income tax expense not allocated to any segment.

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The amount of interest expense not allocated to any segment.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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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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The other noncash expense, not otherwise specified in the taxonomy, charged against earnings in the period to allocate the cost of tangible and intangible assets over their remaining economic lives.

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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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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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Amount of revenue from transactions with other operating segments of the same entity. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss

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Amount of total revenue for the reportable segment, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

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Total of reconciling items between total reportable segments' assets and consolidated entity assets.

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Total assets for reportable segments.

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