Consolidated Statements of Changes in Shareholders' Equity (USD $) In Thousands, except Share data	Total	Preferred Stock [Member]	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]
Balance, value at Dec. 31, 2008	$ 415,385	$ 73,743	$ 233,192	$ 103,061	$ 5,389
Balance (in shares) at Dec. 31, 2008		77,000	18,151,000
Net income (loss)	(3,968)			(3,968)
Other comprehensive income	6,427				6,427
Accretion of preferred stock discount	0	558		(558)
Issuance of common stock, net of offering costs, value	113,537		113,537
Issuance of common stock, net of offering costs, shares			9,775,000
Issuance of common stock - stock option and other plans, value	1,085		1,085
Issuance of common stock - stock option and other plans, shares			100,000
Issuance of common stock - restricted stock awards, net of canceled awards, value	1,038		1,038
Issuance of common stock - restricted stock awards, net of canceled awards, shares			103,000
Tax benefit deficiency associated with share-based compensation	(146)		(146)
Preferred dividends	(3,845)			(3,845)
Cash dividends paid on common stock	(1,374)			(1,374)
Balance, value at Dec. 31, 2009	528,139	74,301	348,706	93,316	11,816
Balance (in shares) at Dec. 31, 2009		77,000	28,129,000
Net income (loss)	30,784			30,784
Other comprehensive income	465				465
Accretion of preferred stock discount	0	2,597		(2,597)
Redemption of preferred stock and common stock warrant	(80,200)	(76,898)	(3,302)
Redemption of preferred stock and common stock warrant (in shares)		(77,000)
Issuance of common stock, net of offering costs, value	229,129		229,129
Issuance of common stock, net of offering costs, shares			11,040,000
Issuance of common stock - stock option and other plans, value	923		923
Issuance of common stock - stock option and other plans, shares			69,000
Issuance of common stock - restricted stock awards, net of canceled awards, value	1,424		1,424
Issuance of common stock - restricted stock awards, net of canceled awards, shares			100,000
Tax benefit deficiency associated with share-based compensation	25		25
Preferred dividends	(2,350)			(2,350)
Cash dividends paid on common stock	(1,461)			(1,461)
Balance, value at Dec. 31, 2010	706,878	0	576,905	117,692	12,281
Balance (in shares) at Dec. 31, 2010		0	39,338,000
Net income (loss)	48,037			48,037
Other comprehensive income	12,852				12,852
Issuance of common stock - stock option and other plans, value	848		848
Issuance of common stock - stock option and other plans, shares	12,126		51,000
Issuance of common stock - restricted stock awards, net of canceled awards, value	1,635		1,635
Issuance of common stock - restricted stock awards, net of canceled awards, shares			119,000
Tax benefit deficiency associated with share-based compensation	(220)		(220)
Purchase and retirement of common stock (in shares)			(2,000)
Purchase and retirement of common stock, value	(32)		(32)
Cash dividends paid on common stock	(10,660)			(10,660)
Balance, value at Dec. 31, 2011	$ 759,338	$ 0	$ 579,136	$ 155,069	$ 25,133
Balance (in shares) at Dec. 31, 2011		0	39,506,000