Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Calculations for basic and diluted earnings per common share
Net income (loss)	$ 34,382	$ (2,779)	$ 57,235	$ (29,168)	$ (856)
Preferred stock dividends and discount accretion	(8,812)	(7,377)	(16,225)	(14,742)
Net income (loss) available to common equity	25,570	(10,156)	41,010	(43,910)
Common shareholder dividends	(1,733)	(1,729)	(3,466)	(3,457)
Unvested share-based payment awards	(12)	(7)	(21)	(15)
Undistributed earnings	23,825	(11,892)	37,523	(47,382)
Basic
Distributed earnings to common shareholders	1,733	1,729	3,466	3,457
Undistributed earnings to common shareholders	23,668	(11,892)	37,293	(47,382)
Total common shareholders earnings, basic	25,401	(10,163)	40,759	(43,925)
Diluted
Distributed earnings to common shareholders	1,733	1,729	3,466	3,457
Undistributed earnings to common shareholders	23,668	(11,892)	37,293	(47,382)
Total common shareholders earnings, diluted	$ 25,401	$ (10,163)	$ 40,759	$ (43,925)
Weighted average common shares outstanding	173,323,000	172,921,000	173,268,000	169,401,000
Effect of dilutive common stock awards	4,000	0	4,000	0
Diluted weighted average common shares outstanding	173,327,000	172,921,000	173,272,000	169,401,000
Basic earnings (loss) per common share	$ 0.15	$ (0.06)	$ 0.24	$ (0.26)
Diluted earnings (loss) per common share	$ 0.15	$ (0.06)	$ 0.24	$ (0.26)
Earnings Per Share (Textuals) [Abstract]
Number of antidilutive stock options excluded from the computation of diluted earnings per share	6,000,000		5,000,000