Basis point adjustment to discount rate on early redemptions of senior notes prior to June 15, 2016

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- Definition

Early Redemption Premium on Senior Notes Redeemed Prior to June 15, 2016

+ References

No definition available.

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- Definition

Interest rate per annum increase if terms of registrations rights agreement are not met

+ References

No definition available.

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- Definition

Line of Credit Facility, Incremental Increase

+ References

No definition available.

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- Definition

Line of Credit Facility, Maximum Borrowing Incremental Increases

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No definition available.

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- Definition

Margin added to Prime Rate to determine effective interest rate

+ References

No definition available.

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- Definition

Percentage of line of credit facility fronting fee.

+ References

No definition available.

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- Definition

rate charged on letters of credit

+ References

No definition available.

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- Definition

Redemption premium required to be offered on senior notes in the event of a change in control

+ References

No definition available.

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- Definition

Senior Notes Redemable Prior to June 15, 2016

+ References

No definition available.

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- Definition

Senior Unsecured Indebtedness Threshold included in the original debt facility which was removed in debt amendment.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

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-Name Regulation S-X (SX)

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-Section 02

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Interest rate stated in the contractual debt agreement.

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

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- Definition

Amount of interest capitalized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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-Topic 210

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Paragraph 2, 4

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-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.19(b),22(b))

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-Number 210

-Section 02

-Paragraph 19, 22

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Name Statement of Financial Accounting Standard (FAS)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Section 45

-Paragraph 14

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.16)

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-Name Regulation S-X (SX)

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-Name Accounting Standards Codification

-Topic 944

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt (Details Textual)	6 Months Ended				3 Months Ended	6 Months Ended				3 Months Ended		1 Months Ended	3 Months Ended		6 Months Ended						3 Months Ended		6 Months Ended								0 Months Ended		3 Months Ended			6 Months Ended					6 Months Ended
Long-Term Debt (Details Textual)	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 14, 2013 USD ($)	Dec. 31, 2012 USD ($)	Jun. 30, 2013 Senior Notes [Member] USD ($)	Jun. 30, 2013 Issuance of Equity [Member]	Jun. 30, 2013 Registration Payment Arrangement, Arrangement [Domain]	Jun. 30, 2013 Registration Payment Arrangement, Arrangement [Domain] Minimum [Member]	Jun. 30, 2013 Registration Payment Arrangement, Arrangement [Domain] Maximum [Member]	Jun. 30, 2013 Corporate [Member] Letter of Credit [Member] USD ($)	Jun. 30, 2013 Corporate [Member] Letter of Credit [Member] Maximum [Member] USD ($)	May 31, 2013 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2012 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2012 Corporate [Member] Revolving Credit Facility [Member] USD ($)	May 03, 2013 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Apr. 22, 2013 Corporate [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 Corporate [Member] Revolving Credit Facility [Member] Maximum [Member] USD ($)	May 03, 2013 Corporate [Member] Revolving Credit Facility [Member] Maximum [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] USD ($)	Jun. 30, 2012 SemMexico [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] USD ($)	Jun. 30, 2012 SemMexico [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] Letter of Credit [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] Letter of Credit [Member] MXN	Jun. 30, 2013 SemMexico [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] Revolving Credit Facility [Member] MXN	Jun. 30, 2013 SemMexico [Member] Revolving Credit Agreements [Member] Additional Credit Agreement [Member] USD ($)	Jun. 30, 2013 SemMexico [Member] Revolving Credit Agreements [Member] Additional Credit Agreement [Member] MXN	Jan. 11, 2013 Rose Rock Midstream L P [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Bilateral Letter of Credit [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Letter of Credit [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2012 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2012 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] USD ($)	Jan. 13, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] Eurodollar Rate Borrowings [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] Alternate Base Rate Borrowings [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] Minimum [Member]	Jun. 30, 2013 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] Maximum [Member]	Dec. 31, 2012 Rose Rock Midstream L P [Member] Revolving Credit Facility [Member] Rose Rock Credit Facility [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] 1.75% Letter of Credit [Member] Bilateral Letter of Credit [Member] USD ($)	Jun. 30, 2013 Rose Rock Midstream L P [Member] 2.0% Letter of Credit [Member] Bilateral Letter of Credit [Member] USD ($)
Debt Instrument [Line Items]
Senior Notes Redemable Prior to June 15, 2016	35.00%
Early Redemption Premium on Senior Notes Redeemed Prior to June 15, 2016	1.00%					107.50%
Basis point adjustment to discount rate	50
Redemption premium on senior notes in the event of a change in control	101.00%
Interest rate increase							0.25%	0.25%	1.00%
Senior Notes	$ 300,000,000		$ 300,000,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage					7.50%
Proceeds from Issuance of Senior Long-term Debt		294,000,000
Long Term Debt (Textual) [Abstract]
Capacity of revolving credit facility																																						385,000,000					150,000,000
Proceeds from Lines of Credit																															133,500,000
Borrowings outstanding													0		0												0		4,300,000	56,000,000									100,000,000	66,500,000
Letters of credit outstanding										4,500,000															22,600,000	292,800,000						8,600,000	37,400,000											600,000	8,000,000
Interest rate in effect																																												1.75%	2.00%
Fees charged on outstanding letters of credit effect rate										2.50%															0.50%	0.50%							3.00%
Percentage of line of credit facility fronting fee										0.25%																							0.25%
Commitment fee on unused capacity													0.50%																												0.375%	0.50%
Unamortized debt costs					6,200,000								5,200,000		5,200,000																			2,700,000		2,700,000
Maximum borrowing capacity											250,000,000						500,000,000		500,000,000								3,400,000	44,000,000	4,300,000	56,000,000
Margin added to Prime Rate to determine effective interest rate																											2.00%	2.00%	1.70%	1.70%
Interest expense recorded					1,100,000								1,500,000	1,600,000	2,800,000	3,200,000					100,000	100,000	100,000	100,000										2,500,000	500,000	4,200,000	1,000,000
Line of Credit Facility, Maximum Borrowing Incremental Increases																		300,000,000		100,000,000														165,000,000		165,000,000
Senior Unsecured Indebtedness Threshold																		200,000,000
Line of Credit Facility, Incremental Increase																	200,000,000
Effective interest rate																													6.01%	6.01%									3.20%	5.25%
Debt Issuance Cost												2,200,000																								1,600,000
Interest Costs Capitalized	1,800,000	100,000
Long-term Debt, Fair Value	$ 303,000,000