Employee Share-based Incentives - Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]
Cost of prior grants of restricted stock units (“RSUs”), performance share units (“PSUs”) and stock appreciation rights (“SARs”) that are amortized over their applicable vesting periods	$ 363	$ 292	$ 1,169	$ 941
Accrual of estimated costs of share-based awards to be granted in future periods, predominantly those to full-career eligible employees	419	392	1,317	1,368
Total noncash compensation expense related to employee share-based incentive plans	$ 782	$ 684	$ 2,486	$ 2,309