Class Of Warrant Issued

No definition available.

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- Definition

Pre-Tax Gain on Extinguishment of Obligations

+ References

No definition available.

+ Details

Name:	ambc_PretaxGainOnExtinguishmentOfObligations
Namespace Prefix:	ambc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

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 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_Cash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementScenarioAxis=ambc_ReorganizationItemAdjustmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Period Type:

Fresh Start Financial Statement Reporting - Fresh Start Reorganized Condensed Consolidated Balance Sheet (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	May. 01, 2013	Apr. 30, 2013
Fresh-Start Adjustment [Line Items]
Common stock, shares issued				45,000,000
Number of warrants issued				5,047,138
Pre-tax gain on extinguishment of obligations				$ 1,521,435
Reorganization Item Adjustments [Member]
Fresh-Start Adjustment [Line Items]
Cash				(101,900)
Successor [Member]
Fresh-Start Adjustment [Line Items]
Cash				$ 152,951
Common stock, shares issued	45,044,222	45,005,932	45,000,000