Assets Acquired In FDIC-Assisted Acquisitions (Pro Forma Information Of Acquisitions) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net interest income and noninterest income	$ 38,069	$ 65,844	$ 134,799	$ 138,697
Net income (loss)	1,903	8,596	(14,905)	(3,957)
Net income (loss) available to common stockholders	$ 1,076	$ 7,779	$ (17,364)	$ (6,379)
Income (loss) per common share available to common stockholders - basic	$ 0.05	$ 0.33	$ (0.73)	$ (0.27)
Income (loss) per common share available to common stockholders - diluted	$ 0.04	$ 0.33	$ (0.72)	$ (0.27)
Average number of shares outstanding, basic	23,819	23,438	23,800	23,439
Average number of shares outstanding, diluted	23,973	23,559	23,954	23,530