Earnings per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Basic earnings (loss) per share:
Net income (loss)	$ (34,535)us-gaap_NetIncomeLoss	$ 16,798us-gaap_NetIncomeLoss
Less preferred stock dividends	(5,481)	(5,480)
Net income (loss) available to common shareholders	(40,016)	11,318
Weighted average shares	96,783,199	96,606,081
Basic earnings (loss) per share	$ (0.41)us-gaap_EarningsPerShareBasic	$ 0.12us-gaap_EarningsPerShareBasic
Diluted earnings (loss) per share:
Net income (loss)	(34,535)us-gaap_NetIncomeLoss	16,798us-gaap_NetIncomeLoss
Less preferred stock dividends	(5,481)	(5,480)
Net income (loss) available to common shareholders	$ (40,016)	$ 11,318
Weighted average shares	96,783,199	96,606,081
Diluted weighted average shares	96,783,199	96,606,081
Diluted earnings (loss) per share	$ (0.41)us-gaap_EarningsPerShareDiluted	$ 0.12us-gaap_EarningsPerShareDiluted

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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