Convertible Preferred Stock - Additional Information (Detail)	Jul. 25, 2017 USD ($) shares $ / shares	May 10, 2017 USD ($) Investor $ / shares shares	Sep. 30, 2017 shares	Dec. 31, 2016 shares
Class of Stock [Line Items]
Number of accredited investors | Investor		3
Preferred stock, shares outstanding			20,000,000	20,000,000
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Convertible into shares of common stock	12,000,000
Fixed conversion price | $ / shares	$ 0.25
Warrants to purchase common stock, issued	10,645,161
Term of warrants	7 years
Warrants exercise price per share | $ / shares	$ 0.31
Preferred stock, shares outstanding		12,000,000
Voting rights		No voting rights
Series A Preferred Stock [Member] | Maximum [Member]
Class of Stock [Line Items]
Gross proceed of preferred stock | $		$ 3,000,000
Series A Preferred Stock [Member] | Preferred Stock Issued Upon Initial Closing [Member]
Class of Stock [Line Items]
Gross proceed of preferred stock | $		$ 1,302,000
Warrants to purchase common stock, issued		4,621,037
Term of warrants		7 years
Warrants exercise price per share | $ / shares		$ 0.31
Series A Preferred Stock [Member] | Preferred Stock Issued Upon Second Closing [Member]
Class of Stock [Line Items]
Gross proceed of preferred stock | $	$ 1,698,000
Warrants to purchase common stock, issued	6,024,124
Term of warrants	7 years
Warrants exercise price per share | $ / shares	$ 0.31