Derivative Financial Instruments (Schedule Of Fair Value Of Derivative Financial Instruments) (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Derivative [Line Items]
Derivative assets	$ 88,828	$ 51,298	$ 69,034
Derivative liabilities	87,948	45,019	65,198
Interest Rate Contract
Derivative [Line Items]
Derivative assets	80,203	42,779	56,938
Derivative liabilities	80,113	42,458	57,429
Designated as Hedging Instrument
Derivative [Line Items]
Derivative assets	726	269	221
Derivative liabilities	914	989	1,620
Designated as Hedging Instrument | Interest Rate Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative assets	549	242	216
Derivative liabilities	7	846	1,329
Designated as Hedging Instrument | Interest Rate Contract | Fair Value Hedging
Derivative [Line Items]
Derivative assets	177	27	5
Derivative liabilities	907	143	291
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative assets	88,102	51,029	68,813
Derivative liabilities	87,034	44,030	63,578
Not Designated as Hedging Instrument | Interest Rate Contract
Derivative [Line Items]
Derivative assets	79,477	42,510	56,717
Derivative liabilities	79,199	41,469	55,809
Not Designated as Hedging Instrument | Interest Rate Lock Commitments
Derivative [Line Items]
Derivative assets	8,352	7,401	11,836
Derivative liabilities	4,060	171	0
Not Designated as Hedging Instrument | Forward Commitments to Sell Mortgage Loans
Derivative [Line Items]
Derivative assets	0	745	0
Derivative liabilities	3,505	2,275	7,713
Not Designated as Hedging Instrument | Foreign Exchange Contract
Derivative [Line Items]
Derivative assets	273	373	260
Derivative liabilities	$ 270	$ 115	$ 56