Reorganization Under Chapter 11 - Summary of Reorganization Items in Consolidated Statements of Total Comprehensive Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014 Successor Ambac [Member]	Mar. 31, 2013 Predecessor Ambac [Member]
Fresh-Start Adjustment [Line Items]
U.S. Trustee fees	$ 7	$ 10
Professional fees	16	2,049
Total reorganization items	$ 23	$ 2,059

Amount of reorganization items related to debtor-in-possession facility financing costs.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 55

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=29642632&loc=d3e56145-112766

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 45

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=6916575&loc=d3e55730-112764

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Amount of reorganization items related to legal and advisory professional fees related to entities in bankruptcy.

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Total amount of reorganization items.

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