Derivative Financial Instruments (Summary Amounts Included In Consolidated Statement Of Income Related To Derivatives) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest rate swaps and caps | Trading (losses) gains, net
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivative instruments	$ (703)	$ (126)	$ (1,131)	$ (317)
Mortgage banking derivatives | Mortgage banking revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivative instruments	43,292	13	60,559	63
Foreign exchange contracts | Trading (losses) gains, net
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivative instruments	(9)	30	(13)	18
Covered call options | Fees from covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivative instruments	0	643	2,292	2,427
Derivative contract held as economic hedge on MSRs | Mortgage banking revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivative instruments	$ 589	$ 920	$ 4,749	$ 920