Annual report pursuant to Section 13 and 15(d)

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

v3.6.0.2
Shareholders' Equity and Capital Stock - addl information (Details)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 12 Months Ended
Jan. 31, 2016
shares
Jan. 31, 2015
shares
Mar. 31, 2015
shares
Dec. 31, 2016
USD ($)
item
shares
Dec. 31, 2015
USD ($)
shares
Dec. 31, 2014
USD ($)
shares
Dec. 31, 2016
CAD / shares
Dec. 31, 2016
USD ($)
$ / shares
shares
Dec. 31, 2015
CAD / shares
shares
Dec. 31, 2015
$ / shares
shares
Dec. 31, 2014
CAD / shares
shares
Dec. 31, 2014
$ / shares
shares
Dec. 31, 2013
$ / shares
shares
Stockholder's Equity Note [Line Items]                          
Common Stock Shares Issued In Exchange Of Restricted Shares Units 197,374 197,374 215,168 385,010 215,168 182,194              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period       16,620 608,531 1,623,139              
Share Price | CAD / shares             CAD 0.71            
Payments Of Stock Issuance Costs | $       $ 884   $ 50              
Stock Issued During Period, Value, New Issues | $       $ 5,684   $ (50)              
Threshold of combined service and age | item       65                  
Percent or RSUs that vest       281,342 286,223 527,407              
Minimum Service For RSU Plan       5 years                  
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage       10.00%                  
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Outstanding, Number               9,748,934 9,974,407 9,974,407 8,468,614 8,468,614 9,273,659
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number               6,278,230          
Stock based compensation | $       $ 857 $ 893 $ 928              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $       700                  
Proceeds from Stock Options Exercised | $       $ 9 $ 410 $ 1,347              
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       715,638 795,592 259,192              
RSUs vested but not redeemed (in shares)                 280,529 280,529      
RSUs redeemed against tax effect (in shares)   65,361   8,374                  
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares               $ 1.02   $ 1.71   $ 1.20 $ 0.95
Capital Stock                          
Stockholder's Equity Note [Line Items]                          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period       16,620 608,531 1,623,139              
Stock Issued During Period, Shares, New Issues       13,085,979                  
Stock Issued During Period, Value, New Issues | $       $ 5,684   $ (50)              
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 | $               $ 900          
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition       1 year 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                  
RSUs vested but not redeemed (in shares)               212,803          
RSUs redeemed against tax effect (in shares) 15,429                        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | CAD / shares             CAD 0.73       CAD 0.96    
Restricted Stock Units (RSUs) [Member] | Capital Stock                          
Stockholder's Equity Note [Line Items]                          
Number of securities called by each unit               1          
Four and One Half Months After Grant [Member]                          
Stockholder's Equity Note [Line Items]                          
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage       22.00%                  
Nine Months After Grant [Member]                          
Stockholder's Equity Note [Line Items]                          
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage       22.00%                  
Thirteen and One Half Months After Grant [Member]                          
Stockholder's Equity Note [Line Items]                          
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage       22.00%                  
Eighteen Months After Date Of Grant [Member]                          
Stockholder's Equity Note [Line Items]                          
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage       24.00%                  
First Anniversary [Member]                          
Stockholder's Equity Note [Line Items]                          
Share-Based Compensation Arrangement By Share-Based Payment Award, Restricted Share Units Vesting Percentage       50.00%                  
Second Anniversary [Member]                          
Stockholder's Equity Note [Line Items]                          
Percent or RSUs that vest       100                  
Share-Based Compensation Arrangement By Share-Based Payment Award, Restricted Share Units Vesting Percentage       50.00%                  
Maximum | Restricted Stock Units (RSUs) [Member]                          
Stockholder's Equity Note [Line Items]                          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | CAD / shares                 CAD 1.22        
Minimum | Restricted Stock Units (RSUs) [Member]                          
Stockholder's Equity Note [Line Items]                          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price | CAD / shares                 CAD 0.80