v3.19.3.a.u2

Convertible debentures - Series E Debentures (Details) $ / shares in Units, $ in Thousands, $ in Millions | Feb. 02, 2018 CAD ($) | Jan. 29, 2018 CAD ($) item $ / shares | Dec. 31, 2019 USD ($) | Apr. 10, 2019 CAD ($) | Dec. 31, 2018 USD ($) | Mar. 03, 2018 CAD ($) | Mar. 02, 2018 CAD ($)
--- | --- | --- | --- | --- | --- | --- | ---
Convertible debentures |  |  |  |  |  |  |
Accrued interest |  |  | $ 2.6 |  | $ 2.3 |  |
Series E Debentures |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Sale offering, principal amount |  | $ 100,000 |  |  |  |  |
Amount of underwriters option to purchase additional debentures |  | 15,000 |  |  |  |  |
Sale of offering, principal amount after issuance costs |  | $ 94,700 |  |  |  |  |
Series E Debentures | Maximum |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Period of underwriters option to purchase |  | 30 days |  |  |  |  |
Series E Debentures | Over-Allotment Option |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Net proceeds from issuance of convertible debentures, after underwriting discounts and expenses | $ 15,000 |  |  |  |  |  |
Sale of offering, principal amount after issuance costs |  | $ 14,400 |  |  |  |  |
Series E Debentures | 6.00% Debenture Due January 31, 2025 |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Conversion debt principal amount |  | $ 1,000 |  |  |  |  |
Conversion rate of the debentures (in Shares per Dollar) |  | 238.0952 |  |  |  |  |
Conversion price of shares (in dollars per share) | $ / shares |  | $ 4.20 |  |  |  |  |
Number of consecutive trading days used to determine weighted average trading price | item |  | 20 |  |  |  |  |
Number of days common stock price must exceed threshold percentage | item |  | 5 |  |  |  |  |
Series E Debentures | 6.00% Debenture Due January 31, 2025 | Maximum |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Period of prior notice of redemption |  | 60 days |  |  |  |  |
Series E Debentures | 6.00% Debenture Due January 31, 2025 | Minimum |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Period of prior notice of redemption |  | 30 days |  |  |  |  |
Debt instrument, redemption price threshold, percentage |  | 125.00% |  |  |  |  |
Series D Debentures |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Notice to redeem remaining principal amount |  |  |  |  |  | $ 56,200 |
Series D Debentures | 6.00% Debenture due December 2019 |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Accrued interest |  |  |  | $ 400 |  |  |
Notice to redeem remaining principal amount |  |  |  | $ 24,700 |  |  |
Series C Debentures |  |  |  |  |  |  |
Convertible debentures |  |  |  |  |  |  |
Notice to redeem remaining principal amount |  |  |  |  |  |  | $ 42,500

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