Allowance For Loan Losses And Credit Quality (Schedule Of Allowance For Loan Losses For Covered Loan And Non-Covered Loan Portfolios) (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	$ 193,761	$ 136,100
Provision for loan losses before benefit attributable to FDIC loss share agreements	22,385	42,167
Benefit attributable to FDIC loss share agreements	(10,633)	(26,706)
Provision charged to operations	11,752	15,461
Provision recorded through FDIC loss share receivable	10,633	26,706
Write-off on transfers to OREO	(12,997)	(7,325)
Loans charged-off	(17,680)	(5,962)
Recoveries	1,816	5,008
Balance, end of period	187,285	169,988
Covered Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	118,900	73,640
Provision for loan losses before benefit attributable to FDIC loss share agreements	12,815	31,115
Benefit attributable to FDIC loss share agreements	(10,633)	(26,706)
Provision charged to operations	2,182	4,409
Provision recorded through FDIC loss share receivable	10,633	26,706
Write-off on transfers to OREO	(12,689)	(7,325)
Loans charged-off	(13,283)	(225)
Recoveries	19	510
Balance, end of period	105,762	97,715
Non-Covered Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	74,861	62,460
Provision for loan losses before benefit attributable to FDIC loss share agreements	9,570	11,052
Provision charged to operations	9,570	11,052
Write-off on transfers to OREO	(308)
Loans charged-off	(4,397)	(5,737)
Recoveries	1,797	4,498
Balance, end of period	$ 81,523	$ 72,273