Loans Receivable (Schedule Of Loans Receivable) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Loans Receivable [Line Items]
Total loans receivable	$ 7,736,512	$ 7,388,037
Residential Mortgage Loans [Member]
Loans Receivable [Line Items]
Total loans receivable	418,789	499,387
Residential Mortgage Loans [Member] | Residential 1-4 Family [Member]
Loans Receivable [Line Items]
Total loans receivable	409,307	483,244
Residential Mortgage Loans [Member] | Construction/ Owner Occupied [Member]
Loans Receivable [Line Items]
Total loans receivable	9,482	16,143
Commercial Loans [Member]
Loans Receivable [Line Items]
Total loans receivable	5,620,023	5,364,356
Commercial Loans [Member] | Real Estate [Member]
Loans Receivable [Line Items]
Total loans receivable	3,313,863	3,318,982
Commercial Loans [Member] | Business [Member]
Loans Receivable [Line Items]
Total loans receivable	2,306,160	2,045,374
Consumer And Other Loans [Member]
Loans Receivable [Line Items]
Total loans receivable	1,697,700	1,524,294
Consumer And Other Loans [Member] | Indirect Automobile [Member]
Loans Receivable [Line Items]
Total loans receivable	309,855	261,896
Consumer And Other Loans [Member] | Home Equity [Member]
Loans Receivable [Line Items]
Total loans receivable	1,159,899	1,061,437
Consumer And Other Loans [Member] | Consumer - Other [Member]
Loans Receivable [Line Items]
Total loans receivable	$ 227,946	$ 200,961