Contracts Accounted for as Credit Derivatives - Credit Derivatives Subordination and Ratings (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Credit Derivatives
Estimated remaining weighted average life of credit derivatives (in years)	12 years 10 months 24 days	13 years 2 months 12 days
Net Par Outstanding on Credit Derivatives
Net Par Outstanding	$ 3,117	$ 4,040
Net Fair Value Asset (Liability)	(194)	(154)
Expected loss to be recovered	(4)	(5)
Public finance | United States
Net Par Outstanding on Credit Derivatives
Net Par Outstanding	1,191	1,705
Net Fair Value Asset (Liability)	(99)	(72)
Public finance | Non United States
Net Par Outstanding on Credit Derivatives
Net Par Outstanding	1,467	1,800
Net Fair Value Asset (Liability)	(67)	(48)
Structured finance | United States
Net Par Outstanding on Credit Derivatives
Net Par Outstanding	347	400
Net Fair Value Asset (Liability)	(25)	(32)
Structured finance | Non United States
Net Par Outstanding on Credit Derivatives
Net Par Outstanding	112	135
Net Fair Value Asset (Liability)	$ (3)	$ (2)