Net Income Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Basic net income per share:	$ 10,815	$ 9,205	$ 22,680	$ 23,576
Less: Preferred Stock dividends and discount accretion	(852)	(1,135)	(1,709)	(2,270)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	9,963	8,070	20,971	21,306
Effect of dilutive stock options and warrants
Net income (loss) available to common stockholders	$ 9,963	$ 8,070	$ 20,971	$ 21,306
Net income (loss) available to common stockholders (in shares)	28,783,407	28,624,609	28,750,197	28,603,612
Effect of dilutive stock options and warrants (in shares)	240,106	190,410	246,577	178,430
Net income (loss) available to common stockholders (in shares)	29,023,513	28,815,019	28,996,774	28,782,042
Net income (loss) available to common stockholders (in dollars per share)	$ 0.35	$ 0.28	$ 0.73	$ 0.74
Diluted net income (loss) per share:
Net income (loss) available to common stockholders (in dollars per share)	$ 0.34	$ 0.28	$ 0.72	$ 0.74