Bank Premises and Equipment - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) branch	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 292	$ 273	$ 270
Impairment losses on bank premises	2	$ 9	$ 7
Land and improvements held for sale
Property, Plant and Equipment [Line Items]
Property transferred to OREO	23
Impairment losses on bank premises	$ 8
Closed In 2023
Property, Plant and Equipment [Line Items]
Number of branches held for sale | branch	30