Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Provision for income tax reconciliation
Loss before provision for income tax	$ 103,913	$ 82,989	$ 15,112	$ 113,419
Federal income tax at statutory rate			(889)	10,293
Permanent items			(5)	10
State income taxes net of federal benefit			35	1,545
Provision on income from Class A units			1,311	8,599
Other			126
Provision for income tax	14,708	16,021	578	20,447
Corporation
Provision for income tax reconciliation
Loss before provision for income tax			(2,541)	29,408
Federal statutory income tax rate (as a percent)			35.00%	35.00%
Federal income tax at statutory rate			(889)	10,293
Permanent items			(5)	10
State income taxes net of federal benefit			(72)	1,049
Provision on income from Class A units			1,311	8,599
Other			126
Provision for income tax			471	19,951
Partnership
Provision for income tax reconciliation
Loss before provision for income tax			20,951	86,615
Federal statutory income tax rate (as a percent)			0.00%	0.00%
State income taxes net of federal benefit			107	496
Provision for income tax			107	496
Eliminations
Provision for income tax reconciliation
Loss before provision for income tax			$ (3,298)	$ (2,604)
Federal statutory income tax rate (as a percent)			0.00%	0.00%

This element represents the income tax expense (benefit) of a taxable wholly-owned subsidiary based on its share of the entity's income resulting from it ownership of Class A units.

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 1
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 47
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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 10

+ Details

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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- Definition

The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible meal and entertainment expenses under enacted tax laws.

+ References

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-Publisher FASB
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- Definition

The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

+ References

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

+ References

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Paragraph h
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