Commitments and Contingencies - Commitments and Contingent Liabilities Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Commitments to extend credit
Home equity lines of credit	$ 8,261,560	$ 5,693,045
Commercial real estate loans to be sold	348,701	324,943
Other commercial real estate	5,776,116	4,998,631
Residential real estate loans to be sold	31,208	233,257
Other residential real estate	505,121	924,211
Commercial and other	32,625,840	22,145,057
Standby letters of credit	2,376,644	2,151,595
Commercial letters of credit	65,066	31,981
Financial guarantees and indemnification contracts	4,022,432	4,211,797
Commitments to sell real estate loans	$ 533,458	$ 1,367,523