Income Taxes (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Income Taxes [Abstract]
Increase (decrease) in unrealized gains (losses) on investments recorded in other comprehensive income			$ 103,900,000	$ 108,700,000
Benefit from income taxes	(74,069,000)	(23,930,000)	(157,162,000)	(88,152,000)
Change in valuation allowance	47,939,000	(2,216,000)	122,654,000	54,156,000
Tax benefit	(26,130,000)	(26,146,000)	(34,508,000)	(33,996,000)
Increase (decrease) in deferred tax valuation allowance, included in other comprehensive income, due to change in deferred tax liability related to unrealized gains/losses on investments	0	0
Total valuation allowance	533,000,000		533,000,000		410,300,000
Net operating loss carryforwards on a regular tax basis	1,320,000,000		1,320,000,000
Net operating loss carryforwards for computing the alternative minimum tax	$ 465,000,000		$ 465,000,000

Deferred income tax expense or benefit related to the change in the deferred tax valuation allowance.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit, excluding the change in the deferred tax valuation allowance, pertaining to pretax income or loss from continuing operations.

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The increase or decrease in the deferred tax valuation allowance that was included in other comprehensive income as it relates to the change in deferred tax liability related to unrealized holding gains/losses on investments.

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- Definition

The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws and used for computing the alternative minimum tax.

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- Definition

Appreciation or loss in value of the total of unsold securities during the period being reported on included in other comprehensive income, before tax.

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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

-Glossary Income Tax Expense (or Benefit)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Subparagraph (a),(b)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

-Subparagraph a, b

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 48

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

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- Definition

The amount of the valuation allowance recorded as of the balance sheet date pertaining to the specified deferred tax asset for which an assessment was made that it is more likely than not that all or a portion of such deferred tax asset will not be realized through related deductions on future tax returns.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Valuation Allowance

-URI http://asc.fasb.org/extlink&oid=6528051

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