Other Liabilities - Additional Information (Detail) - USD ($)		12 Months Ended
	Oct. 30, 2013	Dec. 31, 2015	Oct. 23, 2013
Office Furniture, Equipment and Systems [Member]
Other Liabilities [Line Items]
Interest rate on capital leases		4.64%
Net book value of capital leases		$ 11,000
Common Stock Warrants [Member]
Other Liabilities [Line Items]
Expected volatility		104.00%
Expected term (years)		7 years 9 months 26 days
Risk free rate		2.00%
Silicon Valley Bank [Member]
Other Liabilities [Line Items]
Loan repaid date		Mar. 28, 2014
Term loan facility with Silicon Valley Bank			$ 4,000,000
Term loan, amount borrowed	$ 2,500,000
Warrants expire		2023
Silicon Valley Bank [Member] | Warrants to Purchase Common Stock [Member]
Other Liabilities [Line Items]
Warrants to purchase shares of stock, shares			11,363
Warrants to purchase per share			$ 10.56