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Financial Guarantee Insurance Contracts - Summary of Rollforward of RMBS Subrogation, by Estimation Approach (Parenthetical) (Detail) | 5 Months Ended | 4 Months Ended
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Sep. 30, 2013 Successor Ambac [Member] Transactions | Apr. 30, 2013 Predecessor Ambac [Member] Adverse Samples [Member] Transactions
Summary Of Rollforward Of Subrogation By Estimation Approach [Line Items] |  |
Number of additional transactions added to Random Sample subrogation | 1 |
Number of additional transactions transferred from Random Sample to Adverse Sample population |  | 2
Number of transactions removed from Adverse Sample subrogation population | 2 |

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- Definition Number of Additional Transactions Added to Random Sample Subrogation Population + References No definition available. + Details
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- Definition Number of transaction removed from the Adverse Sample subrogation population. + References No definition available. + Details
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- Definition Number of transactions transferred from Random Sample to Adverse Sample population. + References No definition available. + Details
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- Details
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