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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 | 3 Months Ended
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Mar. 31, 2019 USD ($)
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Total | $ 1,583 |
Collections for Cases | (58) |
Accretion of Recoveries | 10 |
Changes in Discount Rates | 29 |
Changes in Assumptions | 39 |
Changes in LAE Recoveries | 0 |
Other | (1) | [1]
Gross Reserve ending balance, Total | 1,602 |
Insurance Loss Recoverable [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance, Insurance loss recoverable | 1,564 |
Collections for Cases | (58) |
Accretion of Recoveries | 10 |
Changes in Discount Rates | 28 |
Changes in Assumptions | 40 | [2]
Changes in LAE Recoveries | 0 |
Other | (1) | [1]
Gross Reserve ending balance, Insurance loss recoverable | 1,583 |
Recoveries On Unpaid Losses [Member] |  |
Loss And Loss Adjustment Expense Recoveries [Line Items] |  |
Gross Reserve beginning balance,Recoveries on unpaid losses | 19 | [3]
Collections for Cases | 0 |
Accretion of Recoveries | 0 | [3]
Changes in Discount Rates | 1 | [3]
Changes in Assumptions | (1) | [3]
Changes in LAE Recoveries | 0 | [3]
Other | 0 |
Gross Reserve ending balance, Recoveries on unpaid losses | $ 19 | [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 March 31, 2019 and December 31, 2018, excludes Puerto Rico recoveries, which have been netted against reserves.

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