Financial Instruments - Additional Information (Detail) - Credit risk [member]
$ in Thousands
12 Months Ended
Dec. 31, 2017
CAD ($)
Customer
Dec. 31, 2016
CAD ($)
Customer
Disclosure of detailed information about financial instruments [line items]    
Loans receivable $ 314 $ 309
Accounts receivable $ 1,140 $ 107
Percentages of receivables 1.40% 1.00%
Trade receivables [member]    
Disclosure of detailed information about financial instruments [line items]    
Percentage Of Trade Receivable 89.30% 27.50%
Number Of Customers | Customer 2 1