Offsetting Arrangements - Repo, Sec Lending Transactions Maturity by Category (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 256,436	$ 227,222
Securities lending transactions	25,700	22,810
Gross amount of recognized liabilities for repurchase agreements and securities lending	282,136	250,032
U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	256,436	227,222
Securities lending transactions	2,578	152
Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	205	193
Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	13,175	15,713
Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	9,742	6,752
Non-U.S. sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Overnight and Continuous
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	252,768	223,095
Securities lending transactions	21,719	18,278
Gross amount of recognized liabilities for repurchase agreements and securities lending	274,487	241,373
Overnight and Continuous | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	252,768	223,095
Securities lending transactions	2,578	152
Overnight and Continuous | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	205	193
Overnight and Continuous | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	9,194	11,181
Overnight and Continuous | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	9,742	6,752
Overnight and Continuous | Non-U.S. sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Up to 30 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	350
Securities lending transactions	0	13
Gross amount of recognized liabilities for repurchase agreements and securities lending	0	363
Up to 30 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	350
Securities lending transactions	0	0
Up to 30 Days | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
Up to 30 Days | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	13
Up to 30 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
Up to 30 Days | Non-U.S. sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
30-90 days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	979	1,277
Securities lending transactions	15	0
Gross amount of recognized liabilities for repurchase agreements and securities lending	994	1,277
30-90 days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	979	1,277
Securities lending transactions	0	0
30-90 days | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
30-90 days | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	15	0
30-90 days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
30-90 days | Non-U.S. sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Greater than 90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	2,689	2,500
Securities lending transactions	3,966	4,519
Gross amount of recognized liabilities for repurchase agreements and securities lending	6,655	7,019
Greater than 90 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	2,689	2,500
Securities lending transactions	0	0
Greater than 90 Days | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
Greater than 90 Days | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	3,966	4,519
Greater than 90 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
Greater than 90 Days | Non-U.S. sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 0	$ 0