The amount of outstanding principal on amended plantation note after payment.

Name:	kmp_AmountOfOutstandingPrincipalOnAmendedPlantationNoteAfterPayment
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of principal payments on Plantation Note received during period.

+ Details

Name:	kmp_AmountOfPrincipalPaymentsOnPlantationNoteReceivedDuringPeriod
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

The date on which the Plantation note was amended.

+ Details

Name:	kmp_DatePlantationNoteAmended
Namespace Prefix:	kmp
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	kmp_DerivativeCounterpartiesAbstract
Namespace Prefix:	kmp
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element is the costs in the period resulting from expenses related to going-private.

+ Details

Name:	kmp_GoingPrivateTransactionExpenses
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

An agreement (contract) that contingently requires the guarantor to make payments on behalf of the guaranteed party in the event the guaranteed party is unable to meet its obligations.

+ Details

Name:	kmp_IndemnificationGuarantee
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The initial amount of the long-term debt security, a portion of which was acquired with investment in pipeline system

+ Details

Name:	kmp_InitialBalanceOfDebtSecurityPortionOfWhichAcquiredInInvestment
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Interest rate on amended Plantation note

+ Details

Name:	kmp_InterestRateOnAmendedPlantationNote
Namespace Prefix:	kmp
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Kinder Morgan's share of amended note with Plantation

+ Details

Name:	kmp_KinderMorganSShareOfAmendedNoteWithPlantation
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

KMI special bonus expense paid to non-senior management employees during the period.

+ Details

Name:	kmp_KmiSpecialBonusExpenseToNonSeniorManagementEmployees
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The maturity date of amended Plantation note.

+ Details

Name:	kmp_MaturityDateOfAmendedPlantationNote
Namespace Prefix:	kmp
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	instant

- Definition

The payment made by Plantation on amendment date.

+ Details

Name:	kmp_PaymentMadeByPlantationOnAmendmentDate
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Principal amount to be paid on final payment of amended Plantation note

+ Details

Name:	kmp_PrincipalAmountToBePaidOnFinalPaymentOfAmendedPlantationNote
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

An affiliate's, Goldman Sachs, ownership percentage in the terminal assets acquired by the company from US Development Group LLC in January 2010.

+ Details

Name:	kmp_RelatedPartyAssetsAcquiredOwnershipPercentage
Namespace Prefix:	kmp
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Related party receivables included in Accounts, notes and interest receivable, net

+ Details

Name:	kmp_RelatedPartyReceivablesIncludedInAccountsNotesAndInterestReceivableNet
Namespace Prefix:	kmp
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 4

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B

+ Details

Name:	us-gaap_DerivativeAssetsCurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_DerivativeAssetsLiabilitiesAtFairValueNetByBalanceSheetClassificationAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments which are expected to exist longer than one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

+ Details

Name:	us-gaap_DerivativeAssetsNoncurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17

+ Details

Name:	us-gaap_DerivativeLiabilitiesCurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of after one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 7

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B

+ Details

Name:	us-gaap_DerivativeLiabilitiesNoncurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 46R
-Paragraph 16, 17

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 1
-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 2
-Subparagraph d

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 3
-Article 7

+ Details

Name:	us-gaap_DueFromRelatedParties
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 2
-Subparagraph d

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 3
-Subparagraph a
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 2
-Article 4

+ Details

Name:	us-gaap_DueFromRelatedPartiesCurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due after one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 1
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 2
-Subparagraph d

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 11
-Article 5

+ Details

Name:	us-gaap_DueFromRelatedPartiesNoncurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19
-Subparagraph a
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 1
-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 2
-Subparagraph d

+ Details

Name:	us-gaap_DueToRelatedPartiesCurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph a (1)

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Other expenses included in net income that result in no cash inflows or outflows in the period which are not otherwise defined in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

Name:	us-gaap_OtherNoncashExpense
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maturity or expiration date of arrangements with a related party (that is, leasing and debt arrangements between related parties).

+ Details

Name:	us-gaap_RelatedPartyTransactionDate
Namespace Prefix:	us-gaap
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ Details

Name:	us-gaap_RelatedPartyTransactionRate
Namespace Prefix:	us-gaap
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Related Party Transactions (Details) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended			6 Months Ended			6 Months Ended
	Jun. 30, 2011 USD ($)	Mar. 31, 2011 USD ($)	Jun. 30, 2010 USD ($)	Mar. 31, 2010 USD ($)	Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Dec. 31, 2010 USD ($)	Jun. 30, 2011 Plantation Pipe Line Company [Member] Notes Receivable [Member] USD ($)	Dec. 31, 2010 Plantation Pipe Line Company [Member] Notes Receivable [Member] USD ($)	Jun. 30, 2011 Plantation Pipe Line Company [Member]	Jun. 30, 2011 Express pipeline system [Member] Notes Receivable [Member] USD ($)	Jun. 30, 2011 Express pipeline system [Member] Notes Receivable [Member] CAD	Dec. 31, 2010 Express pipeline system [Member] Notes Receivable [Member] USD ($)	Jun. 30, 2011 Express pipeline system [Member]	Dec. 31, 2010 Rockies Express [Member] Accrued other current liabilities [Member] USD ($)	Jun. 30, 2011 NGPL [Member] Other current assets [Member] USD ($)	Dec. 31, 2010 NGPL [Member] Other current assets [Member] USD ($)	Jun. 30, 2011 KMI [Member] Accounts Payable [Member] USD ($)	Dec. 31, 2010 KMI [Member] Accounts Payable [Member] USD ($)
Related Party Transaction [Line Items]
Related party interest rate (in hundredths)								472.00%			1200.00%	1200.00%
Maturity date								Jul. 20, 2011			Jan. 09, 2023	Jan. 09, 2023
Due from related parties, total	$ 9.3				$ 9.3		$ 15.4
Due from related parties, current								80.7	82.1							2.4	7.2
Total amount of initial investment in long-term debt security												113.6
Due from related parties, noncurrent											117.8		114.2
Due to related parties, current	4.4				4.4		8.8								3.7			3.3	5.1
Amount of debt for which KMI agreed to indemnify us and our general partner	733.5				733.5
Non-cash compensation expense allocated from parent					89.9	2.7
Non-cash compensation expense associated with KMI's going-private transaction	0	2.8	1.3	1.4
Non-cash compensation expense associated with a one-time special cash bonus payment to non-senior management employees					89.9	2.7
Schedule of Equity Method Investments [Line Items]
Ownership interest (in hundredths)										5117.00%				3333.00%
Derivative counterparties [Abstract]
Percentage of ownership Goldman Sachs has in our train terminal assets which were acquired from US Development Group LLC (in hundredths)	4900.00%				4900.00%
Derivatives - asset/(liability) [Abstract]
Current assets	7.6				7.6		0
Noncurrent assets	6.0				6.0		12.7
Current liabilities	(158.2)				(158.2)		(221.4)
Noncurrent liabilities	(52.8)				(52.8)		(57.5)
Amount of principal payments on Plantation Note received during period					1.4
Date Plantation note amended	Jul. 20, 2011				Jul. 20, 2011
Amount of outstanding principal on amended plantation note after payment	100.0				100.0
Payment made by Plantation on amendment date	57.9				57.9
Kinder Morgan's share of amended note with Plantation	51.2				51.2
Maturity date of amended Plantation note	Jul. 20, 2016				Jul. 20, 2016
Interest rate on amended Plantation note	4.25				4.25
Principal amount to be paid on final payment of amended Plantation note	87.8				87.8
Related party receivables included in Accounts, notes and interest receivable, net	$ 6.9				$ 6.9		$ 8.2