Derivative Instruments - Maturity of the Notional Amounts of Derivative Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Less Than 1 Year	$ 219,827
1 - 5 Years	55,557
6 - 10 Years	33,230
11 - 30 Years	23,735
Over 30 Years	2,206
Total	334,555	$ 322,099
Interest rate contracts
Derivative [Line Items]
Less Than 1 Year	10,391
1 - 5 Years	19,232
6 - 10 Years	23,278
11 - 30 Years	21,716
Over 30 Years	0
Total	74,617
Foreign currency contracts
Derivative [Line Items]
Less Than 1 Year	379
1 - 5 Years	1,028
6 - 10 Years	1,775
11 - 30 Years	2,011
Over 30 Years	42
Total	5,235
Equity market contracts
Derivative [Line Items]
Less Than 1 Year	209,057
1 - 5 Years	35,253
6 - 10 Years	8,177
11 - 30 Years	8
Over 30 Years	2,164
Total	254,659
Credit contracts
Derivative [Line Items]
Less Than 1 Year	0
1 - 5 Years	44
6 - 10 Years	0
11 - 30 Years	0
Over 30 Years	0
Total	$ 44