Derivative Instruments and Hedging Activities - Fair Value Asset/(Liability) of Credit Protection Sold (Details) - Credit Protection Sold - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Credit Derivatives
Fair Value Asset (Liability)	$ 5,180	$ 4,591
CDS
Credit Derivatives
Fair Value Asset (Liability)	4,904	4,277
Single-name CDS
Credit Derivatives
Fair Value Asset (Liability)	2,611	2,303
Single-name CDS | Investment grade
Credit Derivatives
Fair Value Asset (Liability)	2,167	1,904
Single-name CDS | Non-investment grade
Credit Derivatives
Fair Value Asset (Liability)	444	399
Index and basket CDS
Credit Derivatives
Fair Value Asset (Liability)	2,293	1,974
Index and basket CDS | Investment grade
Credit Derivatives
Fair Value Asset (Liability)	1,829	1,929
Index and basket CDS | Non-investment grade
Credit Derivatives
Fair Value Asset (Liability)	464	45
Other credit contracts
Credit Derivatives
Fair Value Asset (Liability)	$ 276	$ 314