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v3.25.3

Outstanding Exposure - Financial Guaranty Portfolio by Internal Rating (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 274,875 | $ 261,552
% of total net par outstanding | 100.00% | 100.00%
AAA |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 2,884 | $ 3,081
% of total net par outstanding | 1.00% | 1.20%
AA |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 25,305 | $ 25,962
% of total net par outstanding | 9.30% | 9.90%
A |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 137,206 | $ 127,617
% of total net par outstanding | 49.90% | 48.80%
BBB |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 98,102 | $ 94,710
% of total net par outstanding | 35.70% | 36.20%
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 11,378 | $ 10,182
% of total net par outstanding | 4.10% | 3.90%
Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 263,418 | $ 250,375
Public finance | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 212,091 | $ 201,175
% of total net par outstanding | 100.00% | 100.00%
Public finance | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 51,327 | $ 49,200
% of total net par outstanding | 100.00% | 100.00%
Public finance | AAA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 22 | $ 25
% of total net par outstanding | 0.00% | 0.00%
Public finance | AAA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 1,873 | $ 2,074
% of total net par outstanding | 3.70% | 4.20%
Public finance | AA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 17,346 | $ 17,664
% of total net par outstanding | 8.20% | 8.80%
Public finance | AA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 2,522 | $ 2,854
% of total net par outstanding | 4.90% | 5.80%
Public finance | A | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 121,320 | $ 111,502
% of total net par outstanding | 57.20% | 55.50%
Public finance | A | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 12,422 | $ 13,046
% of total net par outstanding | 24.20% | 26.50%
Public finance | BBB | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 69,807 | $ 69,096
% of total net par outstanding | 32.90% | 34.30%
Public finance | BBB | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 27,581 | $ 24,828
% of total net par outstanding | 53.70% | 50.50%
Public finance | BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 10,525 | $ 9,286
Public finance | BIG | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 3,596 | $ 2,888
% of total net par outstanding | 1.70% | 1.40%
Public finance | BIG | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 6,929 | $ 6,398
% of total net par outstanding | 13.50% | 13.00%
Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 11,457 | $ 11,177
Structured finance | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 8,102 | $ 8,453
% of total net par outstanding | 100.00% | 100.00%
Structured finance | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 3,355 | $ 2,724
% of total net par outstanding | 100.00% | 100.00%
Structured finance | AAA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 474 | $ 512
% of total net par outstanding | 5.80% | 6.10%
Structured finance | AAA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 515 | $ 470
% of total net par outstanding | 15.40% | 17.30%
Structured finance | AA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 5,303 | $ 5,386
% of total net par outstanding | 65.50% | 63.70%
Structured finance | AA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 134 | $ 58
% of total net par outstanding | 4.00% | 2.10%
Structured finance | A | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 766 | $ 952
% of total net par outstanding | 9.50% | 11.30%
Structured finance | A | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 2,698 | $ 2,117
% of total net par outstanding | 80.40% | 77.70%
Structured finance | BBB | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 706 | $ 707
% of total net par outstanding | 8.70% | 8.30%
Structured finance | BBB | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 8 | $ 79
% of total net par outstanding | 0.20% | 2.90%
Structured finance | BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 853 | $ 896
Structured finance | BIG | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 853 | $ 896
% of total net par outstanding | 10.50% | 10.60%
Structured finance | BIG | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 0 | $ 0
% of total net par outstanding | 0.00% | 0.00%

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