Long term debt - Schedule of Long Term Debt (Details) - CAD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Long-term Debt, Current Maturities [Abstract]
Current portion of long term debt	$ 29,996	$ 0
Long-term Debt, Excluding Current Maturities [Abstract]
Less: deferred financing costs (note 14(e))	(1,773)	(1,935)
Long-term portion of debt	265,962	70,065
Long-term Debt, Fiscal Year Maturity [Abstract]
2019	29,200
2020	14,600
2021	500
2022	500
2023 and thereafter	500
Credit facilities
Long-term Debt, Current Maturities [Abstract]
Current portion of long term debt	1,167	0
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term debt, gross, non-current	193,751	32,000
Mortgage
Long-term Debt, Current Maturities [Abstract]
Current portion of long term debt	386	0
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term debt, gross, non-current	19,514	0
Convertible debentures
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term debt, gross, non-current	39,976	40,000
Promissory notes
Long-term Debt, Current Maturities [Abstract]
Current portion of long term debt	28,443	0
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term debt, gross, non-current	14,494	0
Credit facility \| Credit facilities
Long-term Debt, Current Maturities [Abstract]
Current portion of long term debt	0	0
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term portion of debt	$ 192,000	$ 32,000

Long-term Debt, Gross, Non-current

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Long-term Debt, Maturities, Repayments Of Principal In Year Five And Thereafter

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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