Offsetting Arrangements - Repo, Sec Lending Transactions Maturity by Category (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 187,002	$ 101,801
Securities lending transactions	16,467	9,852
Gross amount of recognized liabilities for repurchase agreements and securities lending	203,469	111,653
U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	187,002	101,099
Securities lending transactions	8	44
Non-U.S. 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	156	67
Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	9,434	6,115
Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	6,869	3,626
Overnight and Continuous
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	186,824	101,601
Securities lending transactions	14,524	8,246
Gross amount of recognized liabilities for repurchase agreements and securities lending	201,348	109,847
Overnight and Continuous | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	186,824	100,899
Securities lending transactions	8	44
Overnight and Continuous | Non-U.S. 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	144	67
Overnight and Continuous | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	7,503	4,509
Overnight and Continuous | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	6,869	3,626
Up to 30 Days
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Securities lending transactions	15	0
Gross amount of recognized liabilities for repurchase agreements and securities lending	15	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-U.S. 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	15	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	178	200
Securities lending transactions	32	0
Gross amount of recognized liabilities for repurchase agreements and securities lending	210	200
30-90 days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	178	200
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
30-90 days | Corporate debt securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	12	0
30-90 days | Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	20	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	0	0
Securities lending transactions	1,896	1,606
Gross amount of recognized liabilities for repurchase agreements and securities lending	1,896	1,606
Greater than 90 Days | U.S. Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
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
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	1,896	1,606
Greater than 90 Days | Other
Assets Sold under Agreements to Repurchase [Line Items]
Securities lending transactions	$ 0	$ 0