Annual report pursuant to Section 13 and 15(d)

Shareholders' Equity and Capital Stock - addl information (Details)

v3.19.3.a.u2
Shareholders' Equity and Capital Stock - addl information (Details)
$ / shares in Units, $ / shares in Units, $ in Thousands, $ in Thousands
1 Months Ended 8 Months Ended 12 Months Ended
Sep. 25, 2018
$ / shares
shares
May 27, 2016
USD ($)
Sep. 30, 2018
USD ($)
$ / shares
shares
Feb. 29, 2016
USD ($)
$ / shares
shares
Dec. 31, 2017
$ / shares
shares
Dec. 31, 2019
CAD ($)
item
$ / shares
shares
Dec. 31, 2019
USD ($)
item
shares
Dec. 31, 2018
CAD ($)
$ / shares
shares
Dec. 31, 2018
USD ($)
shares
Dec. 31, 2017
CAD ($)
$ / shares
shares
Dec. 31, 2017
USD ($)
shares
Dec. 31, 2016
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 31, 2018
$ / shares
shares
Dec. 31, 2017
$ / shares
shares
Aug. 19, 2014
USD ($)
Stockholder's Equity Note [Line Items]                                
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Outstanding, Intrinsic Value | $                         $ 43      
Common Stock Shares Issued In Exchange Of Restricted Shares Units           425,038 425,038 505,510 505,510 447,663 447,663          
Common Stock Shares Issued               159,729,403         160,478,059 159,729,403    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period           323,618 323,618 496,838 496,838 871,717 871,717          
Sale of Stock, Consideration Received on Transaction | $                     $ 1,100 $ 105        
Sale of Stock, Consideration Received on Transaction After Deducting Other Costs | $                       $ 13        
Stock Issued During Period, Shares, New Issues                   1,536,169 1,536,169          
Share Price | (per share) $ 0.82         $ 0.76                 $ 0.76  
Shares Authorized Value | $                               $ 100,000
Stock issuance costs       $ 800       $ 902   $ 93            
Payments Of Stock Issuance Costs | $                 $ 902   $ 93          
Proceeds from Issuance of Private Placement | $   $ 10,000 $ 10,000                          
Sale of Stock, Price Per Share | $ / shares       $ 0.50               $ 0.65        
Gross proceeds | $       $ 5,700             $ 1,200 $ 108        
Option period for underwriters     30 days                          
Sale of Stock, Number of Shares Issued in Transaction       12,921,000               164,979        
Option to purchase additional common shares by underwriters     1,829,268                          
Exercise of stock options | $           $ 203   $ 290   $ 542            
Warrant to purchase additional common shares by underwriters     914,634                          
Additional warrants acquired by underwriters     867,756                          
Common shares purchased by acquiring additional warrants by underwriters     433,878                          
Number of RSUs Vested           542,674 542,674 621,092 621,092 575,818 575,818          
Stock Issued During Period, Value, New Issues | $               $ 7,399   $ 1,076            
Threshold of combined service and age | item           65 65                  
Percent or RSUs that vest           542,674 542,674 621,092 621,092 575,818 575,818          
Minimum Service For RSU Plan           5 years 5 years                  
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Outstanding, Number         9,459,401     9,731,612   9,459,401   9,748,934 11,076,583 9,731,612 9,459,401  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number                         6,255,228      
Stock based compensation | $             $ 787   $ 915   $ 891          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $             500                  
Proceeds from Stock Options Exercised | $             $ 203   $ 290   $ 542          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period           713,106 713,106 470,756 470,756 541,658 541,658          
Granted, Options           2,852,386 2,852,386 2,182,955 2,182,955 2,666,644 2,666,644          
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares                       $ 1.02 $ 1.00 $ 1.00 $ 0.97  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | $ / shares         $ 0.90         $ 0.90            
Capital Stock                                
Stockholder's Equity Note [Line Items]                                
Common Stock Shares Issued         146,531,933     159,729,403   146,531,933   143,676,384 160,478,059 159,729,403 146,531,933  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period           323,618 323,618 496,838 496,838 871,717 871,717          
Stock Issued During Period, Shares, New Issues 12,195,122             12,195,122 12,195,122 1,536,169 1,536,169          
Exercise of stock options | $           $ 288   $ 415   $ 795            
Stock Issued During Period, Value, New Issues | $               $ 7,399   $ 1,076            
Warrants                                
Stockholder's Equity Note [Line Items]                                
Number of securities called by each warrant     0.5                          
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares     $ 1.00                          
In Money Stock Option [Member]                                
Stockholder's Equity Note [Line Items]                                
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options | $                         $ 1,500      
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition           2 years 3 months 18 days 2 years 3 months 18 days                  
Restricted Stock Units (RSUs) [Member]                                
Stockholder's Equity Note [Line Items]                                
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options | $                         $ 600      
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition           1 year 7 months 6 days 1 year 7 months 6 days                  
Restricted Stock Units (RSUs) [Member] | Capital Stock                                
Stockholder's Equity Note [Line Items]                                
Number of securities called by each warrant                         1      
Employee Stock Option [Member]                                
Stockholder's Equity Note [Line Items]                                
Vesting period         3 years                      
Proceeds from Stock Options Exercised | $             $ 200   $ 400   $ 500          
First Anniversary [Member] | Employee Stock Option [Member]                                
Stockholder's Equity Note [Line Items]                                
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Percentage         33.30%                      
Second Anniversary [Member]                                
Stockholder's Equity Note [Line Items]                                
Number of RSUs Vested           100 100                  
Percent or RSUs that vest           100 100                  
Second Anniversary [Member] | Employee Stock Option [Member]                                
Stockholder's Equity Note [Line Items]                                
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Percentage         33.30%                      
Third Anniversary (Member) | Employee Stock Option [Member]                                
Stockholder's Equity Note [Line Items]                                
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Percentage         33.40%                      
Maximum                                
Stockholder's Equity Note [Line Items]                                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | $ / shares               $ 0.93                
Minimum                                
Stockholder's Equity Note [Line Items]                                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | $ / shares           $ 0.79   $ 0.91