Income Taxes 3 (Details) (USD $)	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income tax expense reconciliation
Statutory federal income tax expense	$ 84,400,000	$ 122,200,000	$ 24,400,000
State income taxes, net of federal benefit	5,000,000	100,000	(10,500,000)
Effect of noncontrolling interests	(4,600,000)	(4,800,000)	(4,500,000)
Effect of gains (losses) on investments, sales of assets and impairment of assets			1,300,000
Other differences, net	(2,800,000)	400,000	(1,600,000)
Total income tax expense	$ 81,958,000	$ 117,850,000	$ 9,067,000

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

-Subparagraph a, b

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- Definition

The portion of the difference between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the disposition of assets in the period.

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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- Definition

The portion of the difference between total income tax expense (benefit) as reported in the Income Statement for the period and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to noncontrolling interest income (expense) that is exempt from income taxes under enacted tax laws.

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- Definition

The portion of the difference, between total income tax expense (benefit) as reported in the Income Statement for the year/accounting period and the expected income tax expense (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.

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- Definition

The portion of the difference, between total income tax expense (benefit) as reported in the Income Statement for the period and the expected income tax expense (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 (benefit).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 1

-Article 4

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