Notes Payable (Termination Fee Liability) - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	May 21, 2014	Apr. 26, 2012
Line of Credit Facility [Line Items]
Interest	$ 11,623,165	$ 6,016,039
Amortization of termination fee	1,390,924	906,292
Interest expense on debt	1,115,280	0
Chambers Credit Agreement [Member]
Line of Credit Facility [Line Items]
Termination fee liability	6,800,000		9,077,778
Termination fee, gross	12,500,000			50,000
Interest	5,700,000
Termination fee, debt discount	6,800,000			3,000,000
Conversion period - Termination Fee Debt Discount	Feb. 28, 2015
Amortization of termination fee	3,940,689	0
Interest expense on debt	$ 1,189,400	$ 794,118