Members' Capital and Distributions (Details Textuals) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Members' Capital and Distributions (Textuals) [Abstract]
Units available for grant under LTIP	2,254,000
Units available under LTIP eligible to be issued as restricted common units, phantom units or unit awards	1,696,000
Non-cash compensation expense related to the amortization of equity-based compensation under LTIP	$ 5,266,000	$ 3,553,000
Common units issued to settle our EICP and MICP obligations	11,732
Accrued EICP bonuses	654,000
Accrued MICP bonuses	1,256,000
Unrecognized compensation costs related to MICP	1,675,000
Series A preferred units [Member]
Additional Members' Capital and Distributions (Textuals) [Abstract]
Issuance of Units in Units	10,327,022
Gross proceeds from issuance of Series A convertible preferred units	$ 300,000,000

Accrued EICP bonuses.

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- Definition

Accrued MICP bonuses.

+ Details

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- Definition

Additional [Member]s' Capital and Distributions.

+ Details

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- Definition

The number of units sold of each class of unit. Units represent ownership of a public limited liability company. This may include common and preferred units of a publicly listed limited liability company.

+ Details

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- Definition

Members Capital And Distributions.

+ Details

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- Definition

Units Available Under LTIP Eligible To Be Issued As Restricted Common Units Phantom Units Or Unit Awards.

+ Details

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- Definition

Common units issued to settle our EICP and MICP obligations.

+ Details

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- Definition

Unrecognized compensation costs related to MICP.

+ Details

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- Definition

Represents the expense recognized during the period arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

+ Details

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- Definition

The cash inflow from the issuance of preferred limited partners units during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 19
-Subparagraph a

+ Details

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- Definition

The difference between the maximum number of shares authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares already issued upon exercise of options or other share-based awards under the plan, and 2) shares reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ Details

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