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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 | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |  |
Gross Reserve beginning balance, Insurance loss recoverable |  | $ 533 | $ 694
Gross Reserve beginning balance, Total |  | 680 | 900
Collections for Cases with Recoveries |  | (74) | (108)
Accretion of Recoveries |  | 10 | 17
Changes in Discount Rates |  | (1) | 33
Changes in Assumptions |  | 94 | (156)
Changes in LAE Recoveries |  | 5 | 1
Other | [1] | (37) | (7)
Gross Reserve ending balance, Insurance loss recoverable |  | 577 | 533
Gross Reserve ending balance, Total |  | 677 | 680
Insurance Loss Recoverable [Member] |  |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |  |
Gross Reserve beginning balance, Insurance loss recoverable |  | 533 | 694
Collections for Cases with Recoveries |  | (74) | (108)
Accretion of Recoveries |  | 8 | 13
Changes in Discount Rates |  | 1 | 18
Changes in Assumptions |  | 140 | (77)
Changes in LAE Recoveries |  | 6 | 0
Other | [1] | (37) | (7)
Gross Reserve ending balance, Insurance loss recoverable |  | 577 | 533
Recoveries On Unpaid Losses [Member] |  |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |  |
Gross Reserve beginning balance,Recoveries on unpaid losses |  | 147 | 206
Collections for Cases with Recoveries |  | 0 | 0
Accretion of Recoveries |  | 2 | 4
Changes in Discount Rates |  | (2) | 15
Changes in Assumptions |  | (46) | (79)
Changes in LAE Recoveries |  | (1) | 1
Other | [1] | 0 | 0
Gross Reserve ending balance, Recoveries on unpaid losses |  | $ 100 | $ 147
[1] | Primarily changes in amount and timing of collections.

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- Details
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