Premises and Equipment (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation	$ 60,600	$ 57,400	$ 55,100
Operating Lease, Rent Expense	50,500	47,700	45,600
Operating Lease, Right-of-Use Asset	280,502	288,816
Operating lease, payments	32,100	32,900
Premises and Equipment
Property, Plant and Equipment [Line Items]
Operating Lease, Right-of-Use Asset	280,500	288,800
Other Liabilities [Member]
Property, Plant and Equipment [Line Items]
Operating lease, liability	316,392	321,900
Partnership Interest [Member]
Property, Plant and Equipment [Line Items]
Operating Lease, Rent Expense	$ 337	$ 327	$ 322