Net Income Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share [Abstract]
Basic net income (loss) per share:	$ 11,865	$ 14,371
Less: Preferred Stock dividends and discount accretion	(857)	(1,135)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	11,008	13,236
Effect of dilutive stock options and warrants
Net income (loss) available to common stockholders	$ 11,008	$ 13,236
Net income (loss) available to common stockholders	28,716,987	28,582,616
Effect of dilutive stock options and warrants	254,251	172,097
Net income (loss) available to common stockholders (in shares)	28,971,238	28,754,713
Net income (loss) available to common stockholders (in dollars per share)	$ 0.38	$ 0.46
Diluted net income (loss) per share:
Net income (loss) available to common stockholders (in dollars per share)	$ 0.38	$ 0.46