Derivative Financial Instruments Derivative Financial Instruments (Schedule Of Fair Value Of Derivative Financial Instruments) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	$ 56,938	$ 37,841	$ 33,275
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	57,429	36,921	31,451
Other Assets
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	69,034	47,964	43,343
Other Assets | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	221	1,442	2,026
Other Assets | Designated as Hedging Instrument | Interest Rate Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	216	1,390	1,947
Other Assets | Designated as Hedging Instrument | Interest Rate Contract | Fair Value Hedging
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	5	52	79
Other Assets | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	68,813	46,522	41,317
Other Assets | Not Designated as Hedging Instrument | Interest Rate Contract
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	56,717	36,399	31,249
Other Assets | Not Designated as Hedging Instrument | Interest Rate Lock Commitments
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	11,836	10,028	10,010
Other Assets | Not Designated as Hedging Instrument | Forward Commitments to Sell Mortgage Loans
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	0	23	41
Other Assets | Not Designated as Hedging Instrument | Foreign Exchange Contract
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	260	72	17
Other Liabilities
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	65,198	41,180	35,505
Other Liabilities | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	1,620	1,994	2,202
Other Liabilities | Designated as Hedging Instrument | Interest Rate Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	1,329	1,994	2,202
Other Liabilities | Designated as Hedging Instrument | Interest Rate Contract | Fair Value Hedging
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	291	0	0
Other Liabilities | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	63,578	39,186	33,303
Other Liabilities | Not Designated as Hedging Instrument | Interest Rate Contract
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	55,809	34,927	29,249
Other Liabilities | Not Designated as Hedging Instrument | Interest Rate Lock Commitments
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	0	20	31
Other Liabilities | Not Designated as Hedging Instrument | Forward Commitments to Sell Mortgage Loans
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	7,713	4,239	3,986
Other Liabilities | Not Designated as Hedging Instrument | Foreign Exchange Contract
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	$ 56	$ 0	$ 37