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Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Detail) (Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses [Member], USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Insurance Loss Recoverable and Recoveries On Unpaid Losses [Line Items] |  |
Collections for Cases with Recoveries | $ (13) | $ (101)
Accretion of Recoveries | 39 | 73
Changes in Discount Rates | 16 | 117
Changes in Timing of Collections |  |
Changes in Amount of Collections | (145) | (227)
Changes in Assumptions | 462 | 307
Changes in LAE Recoveries | 13 | 12
Gross Reserve beginning balance, Total | 3,608 | 3,427
Gross Reserve ending balance, Total | 3,980 | 3,608
Insurance Loss Recoverable [Member] |  |
Insurance Loss Recoverable and Recoveries On Unpaid Losses [Line Items] |  |
Collections for Cases with Recoveries | (13) | (101)
Accretion of Recoveries | 32 | 57
Changes in Discount Rates | 4 | 49
Changes in Timing of Collections |  |
Changes in Amount of Collections | (145) | (227)
Changes in Assumptions | 700 | 723
Changes in LAE Recoveries | 24 | 14
Gross Reserve beginning balance, Insurance loss recoverable | 3,046 | 2,531
Gross Reserve ending balance, Insurance loss recoverable | 3,648 | 3,046
Recoveries On Unpaid Losses [Member] |  |
Insurance Loss Recoverable and Recoveries On Unpaid Losses [Line Items] |  |
Collections for Cases with Recoveries |  |
Accretion of Recoveries | 7 | 16
Changes in Discount Rates | 12 | 68
Changes in Timing of Collections |  |
Changes in Amount of Collections |  |
Changes in Assumptions | (238) | (416)
Changes in LAE Recoveries | (11) | (2)
Gross Reserve beginning balance, Recoveries on unpaid losses | 562 | 896
Gross Reserve ending balance, Recoveries on unpaid losses | $ 332 | $ 562

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- Definition Gross reserve, recoveries on unpaid losses + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of paid insurance policy claims and LAE expense expected to be recovered. + References No definition available. + Details
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- Definition Insurance Loss Recoverable And Changes In Recoveries Of Unpaid Losses Change In Collections + References No definition available. + Details
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