Regulatory Matters (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Kinder Morgan Interstate Gas Transmission Pipeline - Franklin to Hastings Expansion Project [Abstract]
Dekatherms of capacity requested in filing	10,000
Estimated total cost to complete the Franklin to Hastings expansion project	$ 18.4
FERC Natural Gas Fuel Tracker Proceedings - Trailblazer Pipeline Company [Abstract]
EFAP rate implemented by Trailblazer	0.0814
EFAP rate later approved by FERC	0.0869
Expense recognized as a result of FERC approved EFAP	13.1
EFAP rate Trailblazer has filed a request for	4.78%
FERC Natural Gas Fuel Tracker Proceedings Rockies Express Pipeline [Abstract]
Expense recorded resulting from adjustment to its fuel tracker receivable	$ 8.2

Firm transportation capacity requested in filing for Franklin to Hastings Expansion Project. This is measured in dekatherms per day.

No definition available.

Name:	kmp_DekathermsOfCapacityRequestedInFilingFranklinToHastingsProject
Namespace Prefix:	kmp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The Expansion Fuel Adjustment Percentage rate implimented to comply with prior order.

No definition available.

Name:	kmp_EfapRateImplementedByTrailblazer
Namespace Prefix:	kmp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

The Expansion Fuel Adjustment Percentage later approved by the FERC.

No definition available.

Name:	kmp_EfapRateLaterApprovedByFerc
Namespace Prefix:	kmp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

EFAP rate Trailblazer has filed a request for

No definition available.

Name:	kmp_EfapRateTrailblazerHasFiledRequestFor
Namespace Prefix:	kmp_
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

Estimated total cost to complete the Franklin to Hastings Expansion Project.

No definition available.

Name:	kmp_EstimatedTotalCostToCompleteProjectFranklinToHastingsProject
Namespace Prefix:	kmp_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

The expense recognized as a result of implementing the FERC approved EFAP.

No definition available.

Name:	kmp_ExpenseRecognizedAsResultOfFercApprovedEfap
Namespace Prefix:	kmp_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

The expense recorded resulting from an adjustment to its fuel tracker receivable.

No definition available.

Name:	kmp_ExpenseRecordedResultingFromAdjustmentToItsFuelTrackerReceivable
Namespace Prefix:	kmp_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

Name:	kmp_FercNaturalGasFuelTrackerProceedingsRockiesExpressPipelineAbstract
Namespace Prefix:	kmp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	kmp_FercNaturalGasFuelTrackerProceedingsTrailblazerPipelineCompanyAbstract
Namespace Prefix:	kmp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	kmp_KinderMorganInterstateGasTransmissionPipelineFranklinToHastingsExpansionProjectAbstract
Namespace Prefix:	kmp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration