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v3.23.1

Outstanding Exposure - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022
Schedule of Insured Financial Obligations [Line Items] |  |
Loss Mitigation Securities and other | $ 1,300 | $ 1,300
Net par outstanding | 236,383 | 233,258
Guarantor, maximum exposure | 1,600 |
Puerto Rico |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 1,351 | 1,361
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 506 | 509
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement | Commonwealth of Puerto Rico |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 25 | 25
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement | Puerto Rico Public Buildings Authority |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 4 | 4
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement | Puerto Rico Transportation Authority |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 295 | 298
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement | Puerto Rico Highways Authority |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 182 | 182
Puerto Rico | Puerto Rico Exposures Subject to a Plan Support Agreement | Puerto Rico Electric Power Authority |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 720 | 720
Puerto Rico | Other Public Corporations |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 125 |
Puerto Rico | PRHTA |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 477 |
Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 226,746 | 224,099
Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 9,637 | 9,159
Commitment to Provide Guarantees | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Outstanding commitments to provide guaranties | 808 |
Commitment to Provide Guarantees | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Outstanding commitments to provide guaranties | $ 1,400 |
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Maximum period of liquidity claims (in years) | 1 year |
Net par outstanding | $ 5,882 | 5,892
Residual value insurance policies exposure downgraded | 144 | 144
Net Exposure | 84 | 84
BIG | Puerto Rico |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 1,400 | 1,400
BIG | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | 4,794 | 4,777
BIG | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding | $ 1,088 | $ 1,115
Minimum |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Probability of paying more claims than being reimbursed (as a percent) | 50.00% |

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