Guarantee Arrangements and Pledged Assets and Repurchase Agreements - Offsetting of Resale and Repurchase Agreements and Securities Borrowing and Lending Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Securities purchased under agreements to resell, Gross Amounts Recognized	$ 14,426	$ 17,775
Securities purchased under agreements to resell, Gross Amounts Offset in the Balance Sheet	4,047	3,462
Securities purchased under agreements to resell, Net amounts Presented in the Balance Sheet	10,379	14,313
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Financial Instruments	10,356	14,248
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Receive / Pledged	9	10
Securities purchased under agreements to resell, Net amount	14	55
Securities sold under repurchase agreements, Gross Amounts Recognized	5,326	4,611
Securities sold under repurchase agreements, Gross Amounts Offset in the Balance Sheet	4,047	3,462
Securities sold under repurchase agreements, Net Amounts Presented in the Balance Sheet	1,279	1,149
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance sheet, Financial Instruments	1,279	1,121
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Received / Pledged	0	23
Securities sold under repurchase agreements, Net amount	$ 0	$ 5

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Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

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Amount, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of fund outstanding loaned in form of security resale agreement for purchase and resale of identical or substantially same security at date certain for specified price. Includes security purchased under agreement to resell not subject to master netting arrangement or similar agreement.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell.

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Amount of liability associated with funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price.

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