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Investment Income And Gains And Losses (Significant Inputs Used In Schedule Of Measurement Of Credit Loss Component Recognized In Earnings For Each Significant Class Of ABS) (Details) | 9 Months Ended
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Sep. 30, 2011 | Sep. 30, 2010
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Expected size of losses, Weighted average | 64.58% | [1],[2] | 44.90% | [1],[2]
Current subordination levels, Weighted average | 0.00% | [1],[3] | 5.18% | [1],[3]
Prepayment speed (annual CPR), Weighted average | 15.62 | [1],[3] | 9.08 | [1],[3]
Minimum Range [Member] |  |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Expected size of losses, Range | 1.59% | [4],[5] | 0.21% | [4],[5]
Current subordination levels, Range | 0.00% | [3],[5] | 0.00% | [3],[5]
Prepayment speed (annual CPR), Range | 0.00 | [3],[5] | 0.00 | [3],[5]
Maximum Range [Member] |  |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Expected size of losses, Range | 100.00% | [4],[5] | 100.00% | [4],[5]
Current subordination levels, Range | 29.46% | [3],[5] | 42.16% | [3],[5]
Prepayment speed (annual CPR), Range | 100.00 | [3],[5] | 38.13 | [3],[5]
[1] | Calculated by weighting the relevant input/assumption for each individual security by the outstanding notional of the security
[2] | Represents future expected credit losses on impaired assets expressed as a percentage of total outstanding balance.
[3] |
[4] | Represents future expected credit losses on impaired assets expressed as a percentage of total outstanding balance.
[5] | Represents the range of inputs/assumptions based upon the individual securities within each category.

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- Definition Represents the range of inputs/assumptions used to calculate current level of credit protection (subordination) for the securities, expressed as a percentage of total current underlying loan balance + Details
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- Definition Represents the range of inputs/assumptions used to calculate future expected credit losses on impaired assets expressed as a percentage of total current outstanding balance + Details
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- Definition Represents the range of inputs/assumptions used to calculate the high and low points of lifetime vectors of constant prepayment rates + Details
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- Definition Weighted average current subordination levels represents current level of credit protection (subordination) for the securities, expressed as a percentage of total current underlying loan balance calculated by weighting the relevant assumption for each individual security by current outstanding notional of the security. + Details
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- Definition Weighted average expected size of losses represents future expected credit losses on impaired assets expressed as a percentage of total current outstanding balance calculated by weighting the relevant assumption for each individual security by current outstanding notional of the security. + Details
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- Definition Weighted average prepayment speed represents high and low points of lifetime vectors of constant prepayment rates calculated by weighting the relevant assumption for each individual security by current outstanding notional of the security. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + Details
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