Loans Receivable (Schedule Of Non-Covered Loans Outstanding) (Details) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Loans Receivable [Line Items]
Total non-covered loans receivable	$ 6,546,365	$ 6,053,588
Non-Covered Loans
Loans Receivable [Line Items]
Total non-covered loans receivable	6,546,365	6,053,588
Non-Covered Loans | Residential Mortgage Loans [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	235,221	283,113
Non-Covered Loans | Residential Mortgage Loans [Member] | Residential 1-4 Family [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	225,739	266,970
Non-Covered Loans | Residential Mortgage Loans [Member] | Construction/ Owner Occupied [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	9,482	16,143
Non-Covered Loans | Commercial Loans [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	4,840,988	4,487,509
Non-Covered Loans | Commercial Loans [Member] | Real Estate [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	2,660,509	2,591,013
Non-Covered Loans | Commercial Loans [Member] | Business [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	2,180,479	1,896,496
Non-Covered Loans | Consumer And Other Loans [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	1,470,156	1,282,966
Non-Covered Loans | Consumer And Other Loans [Member] | Indirect Automobile [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	309,855	261,896
Non-Covered Loans | Consumer And Other Loans [Member] | Home Equity [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	942,063	826,463
Non-Covered Loans | Consumer And Other Loans [Member] | Consumer - Other [Member]
Loans Receivable [Line Items]
Total non-covered loans receivable	$ 218,238	$ 194,607