Loans (Activity Of Allowance For Loan Losses) (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Balance balance	$ 35,156	$ 34,576	$ 34,576
Provision for loan losses charged to expense	24,360	22,098	30,341
Loans charged off	(34,167)	(22,714)	(31,623)
Recoveries of loans previously charged off	552	1,278	1,862
Ending balance	$ 25,901	$ 35,238	$ 35,156