Share Capital and Reserves - Summary of Warrants Outstanding (Detail) - $ / shares
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 38,654,654 45,885,172 15,795,422
Exercise price $ 0.242    
Warrants grant date Eighteen January 2013 [member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 2,981,476    
Exercise price $ 0.080    
Expiry January 18, 2018    
Warrants grant date Eight October 2015 [member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 4,101,680    
Exercise price $ 0.310    
Expiry October 8, 2020    
Warrants grant date Twenty Three October 2015 [Member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 1,478,245    
Exercise price $ 0.310    
Expiry October 23, 2020    
Warrants grant date twenty eight October 2015 [member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 9,548    
Exercise price $ 0.310    
Expiry October 28, 2020    
Warrants grant date thirteen May 2016 [member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 8,510,812    
Exercise price $ 0.245    
Expiry May 13, 2021    
Warrants grant date twenty seven May 2016 [member]      
Disclosure of terms and conditions of share-based payment arrangement [line items]      
Number of warrants outstanding 21,572,893    
Exercise price $ 0.245    
Expiry May 27, 2021