Ceded Loss And Loss Expenses Paid Not Yet Recovered

No definition available.

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- Definition

Includes the unexpired portion of financial guarantee premiums ceded on policies as of the balance sheet date and reinsurance recoverables on claims or claim adjustment expense paid by the ceding insurer.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Number of Reinsurers Covering Majority

+ References

No definition available.

+ Details

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- Definition

Percentage of Ceded Reinsurance Recoverable Represented by Top Three

+ References

No definition available.

+ Details

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- Definition

Reinsurance Recoverable Credit Exposure

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reinsurance Recoverable, Gross, All Other

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Uncollateralized Credit Exposure Supoorted by Unlimited Uncapped Indemnity

+ References

No definition available.

+ Details

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

- Definition

Unsecured Reinsurance Recoverable, All Other

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents reinsurance recoverables on paid and unpaid losses and deferred ceded premiums, net of ceded premiums payables due to reinsurers, letters of credit, and collateral posted for the benefit of the cedant.

+ References

No definition available.

+ Details

Name:	ambc_UnsecuredReinsuranceRecoverables
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

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-SubTopic 605
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of allowance for credit loss on reinsurance recoverable.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

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- Details

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Insurance - Summary of Percentage Ceded to Reinsurers and Reinsurance Recoverable and Rating Levels (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Ceded Loss And Loss Expenses Paid Not Yet Recovered	$ 88,194		$ 71,031
Reinsurance Recoverable, Allowance for Credit Loss	100	$ 100
Reinsurance Recoverables, Gross	495,653
Unsecured Reinsurance Recoverables	342,850
Reinsurance Recoverable, Gross, All Other	233,125
Unsecured Reinsurance Recoverable, All Other	130,426
Letters of Credit Outstanding, Amount	$ 82,174
Number of Reinsurers Covering Majority	6
Percentage of Ceded Reinsurance Recoverable Represented by Top Three	53.00%
Uncollateralized Credit Exposure Supoorted by Unlimited Uncapped Indemnity	$ 21,229	23,530
Deferred Ceded Premiums And Reinsurance Recoverables	643,889
Reinsurance Recoverable Credit Exposure	342,850	$ 311,795
Munich Reinsurance Company \| Property and Casualty, Commercial Insurance \| Standard & Poor's, A+ Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	71,226
Unsecured Reinsurance Recoverables	64,278
Everest Reinsurance Company \| Property and Casualty, Commercial Insurance \| Standard & Poor's, A+ Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	17,636
Unsecured Reinsurance Recoverables	18,098
General Reinsurance Company \| Property and Casualty, Commercial Insurance \| Standard Poors A Plus Plus Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	123,107
Unsecured Reinsurance Recoverables	98,528
QBE Insurance Corporation \| Property and Casualty, Commercial Insurance \| Standard & Poor's, A Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	18,208
Unsecured Reinsurance Recoverables	18,208
Lloyds Syndicate 566 \| Property and Casualty, Commercial Insurance \| Standard & Poor's, A+ Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	16,296
Unsecured Reinsurance Recoverables	0
Transatlantic Reinsurance Company \| Property and Casualty, Commercial Insurance \| Standard & Poor's, A+ Rating
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Reinsurance Recoverables, Gross	16,055
Unsecured Reinsurance Recoverables	$ 13,312