Annual reports filed by certain Canadian issuers pursuant to Section 15(d) and Rule 15d-4

Contributed surplus (Schedule of Options Outstanding) (Details)

v3.19.1
Contributed surplus (Schedule of Options Outstanding) (Details)
Dec. 31, 2018
CAD ($)
shares
Years
Dec. 31, 2017
CAD ($)
shares
Dec. 31, 2016
CAD ($)
shares
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 1,474,477 1,498,052 1,961,791
Options outstanding, Weighted average exercise price | $ $ 4.12 $ 2.26 $ 2.23
Options outstanding, Weighted average remaining contractual life (years) | Years 2.98    
Options exercisable, Number | shares 860,753    
Options exercisable, Weighted average exercise price | $ $ 2.33    
Options exercisable, Weighted average remaining contractual life (years) | Years 2.11    
Exercise price range 1.98 - 2.29 [Member]      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 285,939    
Options outstanding, Weighted average exercise price | $ $ 2.08    
Options outstanding, Weighted average remaining contractual life (years) | Years 2.16    
Options exercisable, Number | shares 285,939    
Options exercisable, Weighted average exercise price | $ $ 2.08    
Options exercisable, Weighted average remaining contractual life (years) | Years 2.16    
Exercise price range 2.30 - 2.38 [Member]      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 259,377    
Options outstanding, Weighted average exercise price | $ $ 2.37    
Options outstanding, Weighted average remaining contractual life (years) | Years 1.48    
Options exercisable, Number | shares 259,377    
Options exercisable, Weighted average exercise price | $ $ 2.37    
Options exercisable, Weighted average remaining contractual life (years) | Years 1.48    
Exercise price range 2.39 - 3.01 [Member]      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 310,125    
Options outstanding, Weighted average exercise price | $ $ 2.5    
Options outstanding, Weighted average remaining contractual life (years) | Years 2.63    
Options exercisable, Number | shares 310,125    
Options exercisable, Weighted average exercise price | $ $ 2.5    
Options exercisable, Weighted average remaining contractual life (years) | Years 2.63    
Exercise price range 3.02 - 6.72 [Member]      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 400,625    
Options outstanding, Weighted average exercise price | $ $ 6.36    
Options outstanding, Weighted average remaining contractual life (years) | Years 4.17    
Options exercisable, Number | shares 5,312    
Options exercisable, Weighted average exercise price | $ $ 3.2    
Options exercisable, Weighted average remaining contractual life (years) | Years 0.25    
Exercise price range 6.73 - 7.39 [Member]      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
Options outstanding, Number | shares 218,411    
Options outstanding, Weighted average exercise price | $ $ 7.09    
Options outstanding, Weighted average remaining contractual life (years) | Years 4.17    
Options exercisable, Number | shares    
Options exercisable, Weighted average exercise price | $    
Options exercisable, Weighted average remaining contractual life (years) | Years