Offsetting Arrangements - Repo, Sec Lending Transactions Maturity by Category (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 197,757	$ 101,801
Securities lending transactions	16,605	9,852
Gross amount of recognized liabilities for repurchase agreements and securities lending	214,362	111,653
U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	197,757	101,099
Securities lending transactions	6	44
Non-US sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	702
Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	281	67
Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	9,452	6,115
Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	6,866	3,626
Overnight and Continuous
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	196,212	101,601
Securities lending transactions	14,278	8,246
Gross amount of recognized liabilities for repurchase agreements and securities lending	210,490	109,847
Overnight and Continuous | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	196,212	100,899
Securities lending transactions	6	44
Overnight and Continuous | Non-US sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	702
Overnight and Continuous | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	278	67
Overnight and Continuous | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	7,128	4,509
Overnight and Continuous | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	6,866	3,626
Up to 30 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Securities lending transactions	20	0
Gross amount of recognized liabilities for repurchase agreements and securities lending	20	0
Up to 30 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Securities lending transactions	0	0
Up to 30 Days | Non-US sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	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	20	0
Up to 30 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
30-90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	185	200
Securities lending transactions	16	0
Gross amount of recognized liabilities for repurchase agreements and securities lending	201	200
30-90 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	185	200
Securities lending transactions	0	0
30-90 Days | Non-US sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
30-90 Days | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	3	0
30-90 Days | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	13	0
30-90 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	0	0
Greater than 90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	1,360	0
Securities lending transactions	2,291	1,606
Gross amount of recognized liabilities for repurchase agreements and securities lending	3,651	1,606
Greater than 90 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	1,360	0
Securities lending transactions	0	0
Greater than 90 Days | Non-US sovereign debt
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	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	2,291	1,606
Greater than 90 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	$ 0	$ 0