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Loss And Loss Adjustment Expense Reserves (Summary Of Credit Impairments Related To Derivatives) (Narrative) (Detail) (USD $) | 6 Months Ended
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Jun. 30, 2012 Security Loan
Loss And Loss Adjustment Expense Reserves [Line Items] |
Discount rate of credit impairments | 5.59%
Additional estimated credit impairment on CMBS derivatives | $ 454,000,000
Aggregate ITD credit impairment on CMBS derivatives | 3,200,000,000
Number of structured CMBS commutations | 65
Gross exposure commuted on CMBS insured derivatives | 32,900,000,000
Maximum loans with debt service coverage ratio | $ 75,000,000
Debt service coverage ratio | 1.0
Proprietary performance data on CRE loans, amount | 80,000
Maximum [Member] |
Loss And Loss Adjustment Expense Reserves [Line Items] |
Percentage of loss on liquidation | 2.00%
Minimum [Member] |
Loss And Loss Adjustment Expense Reserves [Line Items] |
Percentage of loss on liquidation | 1.00%

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- Definition Aggregate ITD Credit Impairment On CMBS Derivatives + References No definition available. + Details
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- Definition Discount Rate Of Credit Impairments + References No definition available. + Details
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- Definition Gross exposure commuted on CMBS insured derivatives + References No definition available. + Details
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- Details
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- Definition Percentage Of Loss On Liquidation + References No definition available. + Details
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- Definition The ratio applied to the debt for purposes of determining the number of shares of the equity security into which the debt will be converted. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Conversion Rate -URI http://asc.fasb.org/extlink&oid=6509012 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 4 -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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