Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

-URI http://asc.fasb.org/extlink&oid=6505113

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Contingent Stock Agreement

-URI http://asc.fasb.org/extlink&oid=6508534

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1448-109256

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Weighted-Average Number of Common Shares Outstanding

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Net Income Per Share - Reconciliation of Common Shares Used for Basic and Diluted Earnings Per Share (Detail)	3 Months Ended	5 Months Ended	3 Months Ended	5 Months Ended	3 Months Ended	5 Months Ended	3 Months Ended	5 Months Ended	3 Months Ended	4 Months Ended	9 Months Ended	3 Months Ended	4 Months Ended	9 Months Ended	3 Months Ended	4 Months Ended	9 Months Ended	3 Months Ended	4 Months Ended	9 Months Ended
	Sep. 30, 2013 Successor Ambac [Member]	Sep. 30, 2013 Successor Ambac [Member]	Sep. 30, 2013 Successor Ambac [Member] Restricted Stock Units [Member]	Sep. 30, 2013 Successor Ambac [Member] Restricted Stock Units [Member]	Sep. 30, 2013 Successor Ambac [Member] Stock Options [Member]	Sep. 30, 2013 Successor Ambac [Member] Stock Options [Member]	Sep. 30, 2013 Successor Ambac [Member] Warrants [Member]	Sep. 30, 2013 Successor Ambac [Member] Warrants [Member]	Sep. 30, 2012 Predecessor Ambac [Member]	Apr. 30, 2013 Predecessor Ambac [Member]	Sep. 30, 2012 Predecessor Ambac [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Restricted Stock Units [Member]	Apr. 30, 2013 Predecessor Ambac [Member] Restricted Stock Units [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Restricted Stock Units [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Stock Options [Member]	Apr. 30, 2013 Predecessor Ambac [Member] Stock Options [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Stock Options [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Warrants [Member]	Apr. 30, 2013 Predecessor Ambac [Member] Warrants [Member]	Sep. 30, 2012 Predecessor Ambac [Member] Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of common shares used for basic earnings per share	45,002,463	45,001,741							302,469,966	302,469,544	302,468,502
Effect of potential dilutive shares:
Effect of potential dilutive shares							1,352,412	1,443,874				112,310	109,701
Weighted average number of common shares and potential dilutive shares used for diluted earnings per share	46,354,875	46,445,615							302,582,276	302,579,245	302,468,502
Anti-dilutive shares excluded from reconciliation														71,550	800,575	475,550	846,185