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Income Taxes (Narrative) (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Non-Variable Interest Entities [Line Items] |  |  |
Federal statutory tax rate | 35.00% | 35.00% | 35.00%
Net deferred tax asset | $ 1,200,000,000 |  |
Maximum taxable income projections, years | 20 years |  |
Total deferred tax assets | 1,200,000,000 |  |
Increase in deferred tax asset | 61,000,000 |  |
Decrease accumulated other comprehensive income taxes | 5,000,000 |  |
Decrease in current tax receivable | 6,000,000 |  |
Increase in net income (loss) | 60,000,000 | 1,000,000 | 22,000,000
Cumulative amounts of untaxed earnings | 139,000,000 | 15,000,000 | 3,000,000
Estimated tax liability on disposition of foreign subsidiary | 17,000,000 |  |
Capital loss carryforward | 162,000,000 |  |
NOL carryforward | 1,400,000,000 |  |
Minimum tax credit carryforward | 19,000,000 |  |
Non Variable Interest Entities [Member] |  |  |
Non-Variable Interest Entities [Line Items] |  |  |
Net deferred tax asset | 1,199,000,000 | 1,745,000,000 |
Valuation allowance | 146,000,000 | 236,000,000 |
Valuation allowance decrease | $ 90,000,000 |  |

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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FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: 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 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 S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817 + Details
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