v3.25.2
Outstanding Exposure - BIG Net Par Outstanding (Details)
$ in Millions
Jun. 30, 2025
USD ($)
risk
Dec. 31, 2024
USD ($)
risk
Schedule of Insured Financial Obligations [Line Items]    
Net par outstanding, credit derivative $ 3,838 $ 4,212
Net 272,778 261,552
BIG    
Schedule of Insured Financial Obligations [Line Items]    
Net par outstanding, financial guaranty insurance 10,478 10,150
Net par outstanding, credit derivative 30 32
Net $ 10,508 $ 10,182
Number of risks, financial guaranty insurance | risk 202 207
Number of risks, credit derivative | risk 7 7
Number of risks | risk 209 214
BIG | BIG 1    
Schedule of Insured Financial Obligations [Line Items]    
Net par outstanding, financial guaranty insurance $ 5,528 $ 8,074
Net par outstanding, credit derivative 26 28
Net $ 5,554 $ 8,102
Number of risks, financial guaranty insurance | risk 91 98
Number of risks, credit derivative | risk 3 3
Number of risks | risk 94 101
BIG | BIG 2    
Schedule of Insured Financial Obligations [Line Items]    
Net par outstanding, financial guaranty insurance $ 3,546 $ 702
Net par outstanding, credit derivative 4 4
Net $ 3,550 $ 706
Number of risks, financial guaranty insurance | risk 13 12
Number of risks, credit derivative | risk 1 1
Number of risks | risk 14 13
BIG | BIG 3    
Schedule of Insured Financial Obligations [Line Items]    
Net par outstanding, financial guaranty insurance $ 1,404 $ 1,374
Net par outstanding, credit derivative 0 0
Net $ 1,404 $ 1,374
Number of risks, financial guaranty insurance | risk 98 97
Number of risks, credit derivative | risk 3 3
Number of risks | risk 101 100