Earnings per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Basic earnings per share:
Net income	$ 16,798	$ 67,239
Less preferred stock dividends	(5,480)	(5,480)
Net income available to common shareholders	11,318	61,759
Weighted average shares	96,606,081	98,827,587
Basic earnings per share	$ 0.12	$ 0.62
Diluted earnings per share:
Net income	16,798	67,239
Less preferred stock dividends	(5,480)	(5,480)
Net income available to common shareholders	$ 11,318	$ 61,759
Weighted average shares	96,606,081	98,827,587
Potential dilutive shares from exercise of stock options
Diluted weighted average shares	96,606,081	98,827,587
Diluted earnings per share	$ 0.12	$ 0.62