Outstanding Exposure - Expected Amortization of Net Par Outstanding (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Expected Amortization of Net Par Outstanding [Abstract]
0 to 5 years	$ 58,222
5 to 10 years	57,475
10 to 15 years	47,060
15 to 20 years	32,828
Over 20 years	65,967
Total net par outstanding	261,552	$ 249,153
Public finance
Expected Amortization of Net Par Outstanding [Abstract]
0 to 5 years	52,502
5 to 10 years	54,255
10 to 15 years	46,053
15 to 20 years	32,126
Over 20 years	65,439
Total net par outstanding	250,375	239,296
Structured finance
Expected Amortization of Net Par Outstanding [Abstract]
0 to 5 years	5,720
5 to 10 years	3,220
10 to 15 years	1,007
15 to 20 years	702
Over 20 years	528
Total net par outstanding	$ 11,177	$ 9,857