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Special Purpose Entities, Including Variable Interest Entities - Additional Information (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 USD ($) Transactions Entity | Dec. 31, 2015 USD ($) Entity
Variable Interest Entities [Line Items] |  |
Equity Method Investments | $ 26,471,000 |
Number of RMBS Sold | 17 |
Cash Received From Delaware Trust | $ 146,000,000 |
Number of VIEs AAC Transferred Assets To | 2 |
Number of VIEs Liquidated | 1 |
Secured Debt | $ 122,058,000 |
Par Value of Securities Placed in Trust | 367,986,000 |
Fair Value of Securities Placed in Trust | 381,249,000 | $ 396,100,000
Securities Issued by Delaware Trust | 146,000,000 |
Fair value of special purpose entities | 8,411,000 | 8,696,000
Consolidated VIE assets | 14,150,874,000 | 14,288,497,000
Consolidated VIE liabilities | $ 14,077,034,000 | 14,259,776,000
Asset-Backed Securities and Utility Obligations [Member] |  |
Variable Interest Entities [Line Items] |  |
Weighted average life | 5 years 10 months 15 days |
Average rating of assets held by sponsored special purpose entities | BBB |
Sponsored Variable Interest Entities [Member] |  |
Variable Interest Entities [Line Items] |  |
Number of individual transactions with special purpose entities | Transactions | 15 |
Number of transactions outstanding with special purpose entities | Transactions | 3 |
Total principal amount of debt outstanding | $ 454,510,000 | $ 465,160,000
Consolidated Entities [Member] |  |
Variable Interest Entities [Line Items] |  |
Number of DeConsolidated Variable Interest Entities | 1 |
Number of consolidated Variable Interest Entities | Entity | 15 | 15
variable interest entities deconsolidation gain loss | $ 0 |
London Interbank Offered Rate (LIBOR) [Member] |  |
Variable Interest Entities [Line Items] |  |
Interest Rate on Securities Issued by Delaware Trust | 2.80% |

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- Definition The total principal amount of outstanding debt issued by Ambac's sponsored medium term note special purpose entities. + References No definition available. + Details
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- Definition Interest Rate on Securities Issued by Delaware Trust + References No definition available. + Details
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- Definition Number of consolidated variable interest entities. + References No definition available. + Details
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- Definition The number of asset transfer transactions executed with Ambac's sponsored medium term note special purpose entities that are still outstanding at the reporting date. + References No definition available. + Details
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- Definition The number of asset transfer transactions executed with Ambac's sponsored medium term note special purpose entities since the inception of those entities. + References No definition available. + Details
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- Definition Number of RMBS Sold + References No definition available. + Details
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- Definition Number of VIEs AAC Transferred Assets To + References No definition available. + Details
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- Definition The weighted average remaining life of assets held by Ambac's sponsored medium term note special purpose entities at the reporting date. + References No definition available. + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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- Definition The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5710-111685 + Details
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