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v3.26.1

Outstanding Exposure - Financial Guaranty Portfolio by Internal Rating (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
--- | --- | ---
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 278,600 | $ 277,100
% of total net par outstanding | 100.00% | 100.00%
AAA |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 2,700 | $ 2,800
% of total net par outstanding | 1.00% | 1.00%
AA |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 26,000 | $ 25,000
% of total net par outstanding | 9.30% | 9.00%
A |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 142,100 | $ 140,000
% of total net par outstanding | 51.00% | 50.50%
BBB |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 99,200 | $ 100,500
% of total net par outstanding | 35.60% | 36.30%
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 8,640 | $ 8,760
% of total net par outstanding | 3.10% | 3.20%
Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 265,900 | $ 265,600
Public finance | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 216,400 | $ 215,000
% of total net par outstanding | 100.00% | 100.00%
Public finance | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 49,500 | $ 50,600
% of total net par outstanding | 100.00% | 100.00%
Public finance | AAA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 0 | $ 0
% 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 | $ 1,800 | $ 1,800
% of total net par outstanding | 3.60% | 3.50%
Public finance | AA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 18,600 | $ 18,200
% of total net par outstanding | 8.60% | 8.50%
Public finance | AA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 1,400 | $ 1,500
% of total net par outstanding | 2.90% | 2.90%
Public finance | A | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 126,300 | $ 122,800
% of total net par outstanding | 58.30% | 57.10%
Public finance | A | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 11,400 | $ 13,500
% of total net par outstanding | 23.00% | 26.70%
Public finance | BBB | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 68,100 | $ 70,500
% of total net par outstanding | 31.50% | 32.80%
Public finance | BBB | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 30,500 | $ 29,400
% of total net par outstanding | 61.70% | 58.10%
Public finance | BIG | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 3,400 | $ 3,500
% of total net par outstanding | 1.60% | 1.60%
Public finance | BIG | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 4,400 | $ 4,400
% of total net par outstanding | 8.80% | 8.80%
Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 12,700 | $ 11,500
Structured finance | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 8,300 | $ 7,900
% of total net par outstanding | 100.00% | 100.00%
Structured finance | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 4,400 | $ 3,600
% of total net par outstanding | 100.00% | 100.00%
Structured finance | AAA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 500 | $ 500
% of total net par outstanding | 5.30% | 5.80%
Structured finance | AAA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 400 | $ 500
% of total net par outstanding | 10.10% | 12.60%
Structured finance | AA | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 5,400 | $ 5,200
% of total net par outstanding | 64.70% | 66.40%
Structured finance | AA | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 600 | $ 100
% of total net par outstanding | 13.10% | 3.50%
Structured finance | A | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 1,000 | $ 700
% of total net par outstanding | 13.10% | 8.90%
Structured finance | A | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 3,400 | $ 3,000
% of total net par outstanding | 76.60% | 83.70%
Structured finance | BBB | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 600 | $ 600
% of total net par outstanding | 7.00% | 8.20%
Structured finance | BBB | Non-U.S. public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 0 | $ 0
% of total net par outstanding | 0.20% | 0.20%
Structured finance | BIG | United States |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 800 | $ 900
% of total net par outstanding | 9.90% | 10.70%
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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