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v3.25.1

Outstanding Exposure - Components of BIG Net Par Outstanding (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 263,591 | $ 261,552
Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 252,531 | 250,375
Other structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 9,586 | 9,670
Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 11,060 | 11,177
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 9,542 | 10,182
BIG | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 8,661 | 9,286
BIG | Other structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 76 | 77
BIG | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 881 | 896
BIG | BIG 1 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 7,079 | 8,102
BIG | BIG 1 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 6,980 | 7,998
BIG | BIG 1 | Other structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 0 | 0
BIG | BIG 1 | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 99 | 104
BIG | BIG 2 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 1,099 | 706
BIG | BIG 2 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 1,050 | 656
BIG | BIG 2 | Other structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 20 | 21
BIG | BIG 2 | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 49 | 50
BIG | BIG 3 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 1,364 | 1,374
BIG | BIG 3 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 631 | 632
BIG | BIG 3 | Other structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 56 | 56
BIG | BIG 3 | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 733 | 742
United States | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 202,417 | 201,175
United States | RMBS |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 1,474 | 1,507
United States | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 8,373 | 8,453
United States | BIG | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 2,046 | 2,888
United States | BIG | RMBS |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 805 | 819
United States | BIG | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 881 | 896
United States | BIG | BIG 1 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 904 | 2,119
United States | BIG | BIG 1 | RMBS |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 99 | 104
United States | BIG | BIG 2 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 511 | 137
United States | BIG | BIG 2 | RMBS |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 29 | 29
United States | BIG | BIG 3 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 631 | 632
United States | BIG | BIG 3 | RMBS |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 677 | 686
Non-U.S. public finance | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 50,114 | 49,200
Non-U.S. public finance | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 2,687 | 2,724
Non-U.S. public finance | BIG | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 6,615 | 6,398
Non-U.S. public finance | BIG | Structured finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 0 | 0
Non-U.S. public finance | BIG | BIG 1 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 6,076 | 5,879
Non-U.S. public finance | BIG | BIG 2 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | 539 | 519
Non-U.S. public finance | BIG | BIG 3 | Public finance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net | $ 0 | $ 0

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