Nature of Business and Summary of Significant Accounting Policies - Reconciliation of the Numerators and Denominators of the Basic and Diluted (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basic:
Net (loss) income attributable to common stockholders									$ (57,393,613)	$ 1,652,181	$ (23,325,116)
Weighted average common shares outstanding									37,941,044	30,546,581	28,322,477
Basic earnings per common share	$ (0.33)	$ (0.49)	$ (0.35)	$ (0.34)	$ 0.26	$ (0.58)	$ 0.13	$ 0.23	$ (1.51)	$ 0.05	$ (0.82)
Effect of dilutive securities:
Net (loss) income attributable to common stockholders									(57,393,613)	1,652,181	(23,325,116)
Adjustments to income for dilutive options and warrants
Net (loss) income attributable to common stockholders Diluted									$ (57,393,613)	$ 1,652,181	$ (23,325,116)
Weighted average common shares outstanding									37,941,044	30,546,581	28,322,477
Effect of dilutive options and warrants										142,654
Diluted weighted average common shares outstanding									37,941,044	30,689,235	28,322,477
Diluted earnings per common share	$ (0.33)	$ (0.49)	$ (0.35)	$ (0.34)	$ 0.19	$ (0.58)	$ 0.12	$ 0.23	$ (1.51)	$ 0.05	$ (0.82)