Preferred Stock Warrant Liability - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
	Sep. 30, 2013	Mar. 31, 2015	Mar. 31, 2016	Dec. 31, 2015	Jul. 01, 2015	Jun. 26, 2015
Class of Stock [Line Items]
Fair value of warrant issuance			$ 0	$ 0
Loss from revaluation of preferred stock warrant liability		$ (213,000)
Common Stock [Member] | Initial Public Offering ("IPO") [Member]
Class of Stock [Line Items]
Public offering price per share					$ 18.00	$ 18.00
Series A-2 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Warrants issued to purchase of stock	92,127
Warrants exercise price per share	$ 1.78
Class of warrant or right, contractual term	10 years
Fair value of warrant issuance	$ 156,000	$ 14,870