Commitments and Contingencies - Commitments and Contingent Liabilities Outstanding (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Commitments to extend credit
Commercial and industrial	$ 28,566	$ 27,471
Commercial real estate loans to be sold	916	349
Other commercial real estate	5,019	5,084
Residential real estate loans to be sold	163	31
Other residential real estate	331	505
Home equity lines of credit	8,109	8,262
Credit cards	5,578	5,465
Other	413	382
Standby letters of credit	2,289	2,377
Commercial letters of credit	62	65
Financial guarantees and indemnification contracts	4,036	4,022
Commitments to sell real estate loans	$ 1,400	$ 533