Organization and Business - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended			12 Months Ended
	Jan. 15, 2014	Jun. 29, 2016	Jun. 30, 2015	Jan. 31, 2014	Dec. 31, 2016	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2013
Organization and Nature of Operations [Line Items]
Cash					$ 9,375	$ 13,859	$ 8,854	$ 3,552
Stock issued during period, shares, new issues	5,000,000	5,882,352		5,000,000
Stock issued during period, value, new issues					$ 4,388	$ 13,813
Proceeds from issuance initial public offering	$ 13,800	$ 9,300
Warrant
Organization and Nature of Operations [Line Items]
Stock issued during period, shares, new issues	2,500,000	2,941,176		2,500,000
Stock issued during period, value, new issues	$ 15,000	$ 10,000	$ 25,000
2016 Registered Direct Offering
Organization and Nature of Operations [Line Items]
Proceeds from Issuance Initial Public Offering Net Additional Financing Costs		9,000
Debt Issuance Costs, Net		300
Proceeds from Warrant Exercises		4,300
Proceeds from Issuance of Common Stock		$ 4,700