Guarantee Arrangements and Pledged Assets and Repurchase Agreements - Offsetting of Resale and Repurchase Agreements and Securities Borrowing and Lending Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Securities purchased under agreements to resell, Gross Amounts Recognized	$ 17,775	$ 19,382
Securities purchased under agreements to resell, Gross Amounts Offset in the Balance Sheet	3,462	5,504
Securities purchased under agreements to resell, Net amounts Presented in the Balance Sheet	14,313	13,878
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Financial Instruments	14,248	13,677
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Receive / Pledged	10	7
Securities purchased under agreements to resell, Net amount	55	194
Securities sold under repurchase agreements, Gross Amounts Recognized	4,611	5,771
Securities sold under repurchase agreements, Gross Amounts Offset in the Balance Sheet	3,462	5,504
Securities sold under repurchase agreements, Net Amounts Presented in the Balance Sheet	1,149	267
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance sheet, Financial Instruments	1,121	266
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Received / Pledged	23	0
Securities sold under repurchase agreements, Net amount	$ 5	$ 1