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Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Detail) (USD $) In Millions, unless otherwise specified | 9 Months Ended
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Sep. 30, 2013
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Total | $ 3,980 |
Collections for Cases with Recoveries | (2,981) |
Accretion of Recoveries | 20 |
Changes in Discount Rates | (52) |
Changes in Assumptions | 144 |
Changes in LAE Recoveries | (31) |
Other | (12) | [1]
Gross Reserve ending balance, Total | 1,068 |
Insurance Loss Recoverable [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Insurance loss recoverable | 3,648 |
Collections for Cases with Recoveries | (2,981) |
Accretion of Recoveries | 16 |
Changes in Discount Rates | (25) |
Changes in Assumptions | 129 |
Changes in LAE Recoveries | (33) |
Other | (12) | [1]
Gross Reserve ending balance, Insurance loss recoverable | 742 |
Recoveries On Unpaid Losses [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance,Recoveries on unpaid losses | 332 |
Collections for Cases with Recoveries | 0 |
Accretion of Recoveries | 4 |
Changes in Discount Rates | (27) |
Changes in Assumptions | 15 |
Changes in LAE Recoveries | 2 |
Other | 0 | [1]
Gross Reserve ending balance, Recoveries on unpaid losses | $ 326 |
[1] | Primarily changes in amount and timing of collections.

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- Definition Insurance Loss Recoverable And Changes In Recoveries Of Unpaid Losses Change In Discount Rate + References No definition available. + Details
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- Definition Changes in the timing and amount of net collections on financial guarantee contracts. + References No definition available. + Details
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