Earnings Per Share (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator:
Net loss attributable to common shareholders	$ (11,077,851)	$ (75,909,008)	$ (88,600,000)	$ (62,800,000)	$ (31,900,000)
Denominator:
Weighted average number of common shares outstanding (in shares)	173,365,830	133,750,522