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v3.10.0.1

Background and Business Description - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Feb. 12, 2018 | Dec. 31, 2017 | May 01, 2013
Background And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Entity Incorporation, Date of Incorporation | Apr. 29, 1991 |  |  |  |  |  |
Ambac LSNI Secured Note [Domain] |  |  |  |  |  |  |
Background And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
AMBAC LSNI Secured Note |  |  |  |  | $ 2,154,332 |  |
Successor [Member] |  |  |  |  |  |  |
Background And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Other investments | $ 394,396 |  | $ 394,396 |  |  | $ 431,630 |
Gain (Loss) on Sale of Derivatives | 91 | $ 1,134 | 197 | $ 1,333 |  |  |
Financial Guarantee Insurance Contracts, Accelerated Premium Revenue, Amount | $ 6,103 | $ 13,190 | $ 15,495 | $ 29,470 |  |  |
Common stock, shares authorized | 130,000,000 |  | 130,000,000 |  |  | 130,000,000 |
Common Stock, Par or Stated Value Per Share | $ 0.01 |  | $ 0.01 |  |  | $ 0.01 |
Preferred stock, shares authorized | 20,000,000 |  | 20,000,000 |  |  | 20,000,000 |
Preferred Stock, Par or Stated Value Per Share | $ 0.01 |  | $ 0.01 |  |  | $ 0.01 |
Warrants issued exercise price |  |  |  |  |  |  | $ 16.67
Derivative Liability | $ 67,648 |  | $ 67,648 |  |  | $ 82,782 |

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- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Face amount or stated value per share of common stock. + References Reference 1: 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(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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