Financial Guarantee Insurance - Summary of Percentage Ceded to Reinsurers and Reinsurance Recoverable and Rating Levels (Detail)	Dec. 31, 2024
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items]
Percentage of Ceded Reinsurance Recoverable Represented by Top Three	69.00%

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

No definition available.

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