Organization and Basis of Presentation - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended					0 Months Ended	1 Months Ended
	Aug. 22, 2013	Feb. 28, 2014	Jun. 30, 2014	Dec. 31, 2013		Aug. 22, 2013	Jul. 09, 2014 Subsequent Event [Member]	Jul. 31, 2014 Subsequent Event [Member]	Jul. 31, 2014 Subsequent Event [Member] Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Number of consecutive business days, non-compliance of minimum bid price	30 days
Minimum bid price						$ 1.00
Reverse stock split, common stock							One-for-ten reverse split of its common stock
Reverse stock split ratio, common stock							0.1
Expected period to obtain reimbursement									18 months
Proceeds from sale of Series A Preferred Stock, common stock and warrants		$ 11,500,000
Proceeds from sale of senior secured convertible debt								14,000,000
Accumulated deficit			$ 175,501,426	$ 168,147,878	[1]

[1] Derived from the audited balance sheet as of December 31, 2013