Derivative Financial Instruments 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, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Interest Rate Swaps and Caps | Trading gains (losses), net
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 133	$ (737)	$ (317)	$ (1,414)
Mortgage Banking Derivatives | Mortgage banking revenue
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	299	(4,885)	2,393	(1,208)
Covered Call Options | Fees from covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	4,565	1,244	8,925	2,786
Foreign Exchange Contract | Trading gains (losses), net
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 71	$ (10)	$ 20	$ (11)