Long-Term Debt (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	$ 24
Scheduled principal payments, December 31, 2014	27
Scheduled principal payments, December 31, 2015	28
Scheduled principal payments, December 31, 2016	206,007
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	206,086	109,335
SemGroup corporate revolving credit facility [Member]
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	0
Scheduled principal payments, December 31, 2014	0
Scheduled principal payments, December 31, 2015	0
Scheduled principal payments, December 31, 2016	201,500
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	201,500
Rose Rock Credit Facility [Member]
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	0
Scheduled principal payments, December 31, 2014	0
Scheduled principal payments, December 31, 2015	0
Scheduled principal payments, December 31, 2016	4,500
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	4,500
SemLogistics credit facility [Member]
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	0
Scheduled principal payments, December 31, 2014	0
Scheduled principal payments, December 31, 2015	0
Scheduled principal payments, December 31, 2016	0
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	0
SemMexico credit facility [Member]
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	0
Scheduled principal payments, December 31, 2014	0
Scheduled principal payments, December 31, 2015	0
Scheduled principal payments, December 31, 2016	0
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	0
Capital Leases [Member]
Debt Instrument [Line Items]
Scheduled principal payments, December 31, 2013	24
Scheduled principal payments, December 31, 2014	27
Scheduled principal payments, December 31, 2015	28
Scheduled principal payments, December 31, 2016	7
Scheduled principal payments, December 31, 2017	0
Scheduled principal payments, Thereafter	0
Total long-term debt	$ 86

Long-term Debt and Capital Lease, Maturities, Repayments of Principal in Next Twelve Months

No definition available.

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- Definition

Long-term Debt and Capital Lease, Maturities, Repayments of Principal in Year Three

+ References

No definition available.

+ Details

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- Definition

Long-term Debt and Capital Lease, Maturities, Repayments of Principal in Year Two

+ References

No definition available.

+ Details

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- Definition

Long-term Debt and Capital Leases, Maturities, Repayments of Principal after Year Five

+ References

No definition available.

+ Details

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- Definition

Long-term Debt and Capital Leases, Maturities, Repayments of Principal in Year Five

+ References

No definition available.

+ Details

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- Definition

Long-term Debt and Capital Leases, Maturities, Repayments of Principal in Year Four

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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