Employee Benefit Plans - Earnings Per Share (Details) - shares	1 Months Ended			12 Months Ended
	Jan. 31, 2014	Feb. 28, 2013	May. 31, 2011	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share
Antidilutive shares excluded from calculation of diluted earnings per share				21,652,391	18,614,650	40,464,065
Number of warrants exercised (in shares)				26,882	23,918,429	22,494,987
Warrants issued in May, 2011
Earnings Per Share
Number of warrants issued (in shares)			22,995,365
Number of warrants exercised (in shares)				22,802,898
Warrants issued in February, 2013
Earnings Per Share
Number of warrants issued (in shares)		23,637,500
Number of warrants exercised (in shares)				23,637,400
Warrants issued in January, 2014
Earnings Per Share
Number of warrants issued (in shares)	4,000,000
Number of warrants exercised (in shares)				0
Restricted stock
Earnings Per Share
Antidilutive shares excluded from calculation of diluted earnings per share				204,444	473,336	650,002
Warrants
Earnings Per Share
Antidilutive shares excluded from calculation of diluted earnings per share				4,192,567	4,219,449	24,137,878
Preferred stock
Earnings Per Share
Antidilutive shares excluded from calculation of diluted earnings per share				5,554,594	5,554,594	10,972,859
Stock options
Earnings Per Share
Antidilutive shares excluded from calculation of diluted earnings per share				11,700,786	8,367,271	4,703,326