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Income Taxes (Narrative) (Details) (USD $) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2011 | Sep. 30, 2010 | Dec. 31, 2010
Variable Interest Entity [Line Items] |  |  |
Federal statutory rate | 35.00% |  |
Capital loss carryforwards |  |  | $ 413,000,000
NOL carryforwards | 782,000,000 |  |
Minimum tax credit carryforward | 46,000,000 |  |
Deferred tax assets related to losses on insured credit derivatives | 1,600,000,000 |  |
Insured credit derivatives | 4,500,000,000 |  |
Unrealizable deferred tax assets | 1,300,000,000 |  |
Decrease in cumulative ownership change | 28.60% |  |
Cumulative ownership shift | 50.00% |  |
Percentage of ownership of new owners | 5.00% |  |
Taxable income projection, years | 15Y |  |
Maximum taxable income projection years | 20Y |  |
Deferred tax assets related to unrealized losses on investments | 76,000,000 |  |
Defined testing period for ownership change, approximate years | 3Y |  |
Cumulative undistributed earnings | 38,000,000 | 122,000,000 |
Non Variable Interest Entities [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Deferred income taxes, net | 1,298,000,000 |  | 908,000,000
Valuation allowance | 342,000,000 |  | 376,000,000
Valuation allowance decrease | $ 34,000,000 |  |

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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 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 + Details
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