Employee Share-based Incentives - Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
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	$ 440	$ 424
Accrual of estimated costs of share-based awards to be granted in future periods, predominantly those to full-career eligible employees	733	629
Total noncash compensation expense related to employee share-based incentive plans	$ 1,173	$ 1,053