Share-Based Compensation (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock [Member]
Restricted stock activity
Restricted shares outstanding, beginning of period, shares	1,267,110
Restricted shares outstanding, beginning of period, weighted average price	$ 21.54
Restricted shares granted, shares	747,400
Restricted shares granted, fair value, weighted average price	$ 11.55	$ 14.86	$ 31.12
Restricted shares canceled, shares	(208,206)
Restricted shares canceled, fair value, weighted average price	$ 15.30
Restricted shares vested, shares	(392,292)
Restricted shares vested, weighted average price	$ 30.09
Restricted shares outstanding, end of period, shares	1,414,012	1,267,110
Restricted shares outstanding, end of period, weighted average price	$ 14.81	$ 21.54
Restricted Stock Units (RSUs) [Member]
Restricted stock activity
Restricted shares outstanding, beginning of period, shares	189,700
Restricted shares outstanding, beginning of period, weighted average price	$ 15.01
Restricted shares granted, shares	185,250
Restricted shares granted, fair value, weighted average price	$ 11.68	$ 15.01
Restricted shares canceled, shares	0
Restricted shares canceled, fair value, weighted average price	$ 0.00
Restricted shares vested, shares	0
Restricted shares vested, weighted average price	$ 0.00
Restricted shares outstanding, end of period, shares	374,950	189,700
Restricted shares outstanding, end of period, weighted average price	$ 13.36	$ 15.01