Net Income (Loss) Per Common Share - Calculation of Basic Net Income (Loss) Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Numerator for basic and diluted net income (loss) per share:
Net income (loss)	$ 5,501	$ (3,380)	$ 3,070
Preferred deemed dividend		(9,455)
Series B preferred stock dividends	(4,248)
Net income (loss) attributable to common shareholders	$ 1,253	$ (12,835)
Denominator for basic net income (loss) per share:
Weighted-average shares outstanding	202,343,245	201,978,462
Weighted-average unvested restricted shares outstanding	(1,196,680)	(1,504,392)
Denominator for basic net income (loss) per share:	201,146,565	200,474,070
Basic net income (loss) per share attributable to common shareholders	$ 0.01	$ (0.06)