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Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Detail) $ in Millions | 9 Months Ended
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Sep. 30, 2018 USD ($)
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Total | $ 546 |
Collections for Cases | (42) |
Accretion of Recoveries | 15 |
Changes in Discount Rates | (30) |
Changes in Assumptions | 1,076 |
Changes in LAE Recoveries | (6) |
Other | 4 | [1]
Gross Reserve ending balance, Total | 1,563 |
Insurance Loss Recoverable [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Insurance loss recoverable | 511 |
Collections for Cases | (42) |
Accretion of Recoveries | 14 |
Changes in Discount Rates | (29) |
Changes in Assumptions | 1,084 | [2]
Changes in LAE Recoveries | 0 |
Other | 4 | [1]
Gross Reserve ending balance, Insurance loss recoverable | 1,542 |
Recoveries On Unpaid Losses [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance,Recoveries on unpaid losses | 35 | [3]
Collections for Cases | 0 |
Accretion of Recoveries | 1 | [3]
Changes in Discount Rates | (1) | [3]
Changes in Assumptions | (8) | [3]
Changes in LAE Recoveries | (6) | [3]
Other | 0 |
Gross Reserve ending balance, Recoveries on unpaid losses | $ 21 | [3]
[1] | Primarily changes in amount and timing of collections.
[2] | Includes amounts which have been paid and are expected to be recovered in the future.
[3] | As of September 30, 2018 and December 31, 2017, excludes Puerto Rico recoveries, which have been netted against reserves.

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