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Financial Guarantee Insurance Contracts | 12 Months Ended
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Dec. 31, 2020
Insurance [Abstract] |
Summary of Rollforward of RMBS Subrogation, by Estimation Approach | Below is the rollforward of RMBS R&W subrogation for the affected periods:
Year ended December 31, | 2020 |  | 2019 |  | 2018
Discounted RMBS subrogation recovery (gross of reinsurance) at beginning of year | $ | 1,727 |  |  | $ | 1,771 |  |  | $ | 1,834 |
All other changes (1) | 23 |  |  | (43) |  |  | (64) |
Discounted RMBS subrogation recovery (gross of reinsurance) at end of year | $ | 1,751 |  |  | $ | 1,727 |  |  | $ | 1,771 |
(1)All other changes which may impact RMBS R&W subrogation recoveries include changes in actual or projected collateral performance, changes in the creditworthiness of a sponsor and the projected timing of recoveries.

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- Definition Tabular presentation of rollforward of RMBS subrogation, by estimation approach. + References No definition available. + Details
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- References No definition available. + Details
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