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SHAREHOLDERS' EQUITY (Details) $ / shares in Units, $ in Thousands, $ in Millions |  |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Dec. 19, 2017 USD ($) $ / shares shares | Sep. 22, 2017 USD ($) item $ / shares shares | Apr. 26, 2017 shares | Mar. 31, 2018 USD ($) $ / shares shares | Mar. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2017 CAD ($) | Dec. 31, 2017 USD ($) shares
Shareholders’ distributions |  |  |  | $ 1,686 | $ 1,498 |  |
Common stock issued | shares |  |  |  | 337,086,000 |  |  | 337,051,000
Weighted average exercise price of stock options (in dollars per share) | $ / shares |  |  |  | $ 1.15 | $ 2.34 |  |
Exercise of stock options |  |  |  | $ 40 | $ (47) |  |
Flow-through share premium |  |  |  | 1,000 |  |  | $ 1,643
Restricted cash for exploration activities |  |  |  | 1,200 |  |  |
Decrease in flow through premium |  |  |  | 600 |  |  |
Number of units issued | shares |  | 20,700,000 |  |  |  |  |
Number of warrants issued | item |  | 10,350,000 |  |  |  |  |
Price per unit | $ / shares | $ 2.50 |  |  |  |  |  |
Net proceeds |  | $ 43,200 |  | 39,400 |  |  |
Issuance costs |  | $ 3,400 |  | $ 3,800 |  |  |
Number of warrants remained outstanding and unexercised | shares |  |  |  | 10,350,000 |  |  |
Share price | $ / shares | $ 2.50 |  |  |  |  |  |
Equity Incentive Plan |  |  |  |  |  |  |
Shares of common stock issued upon exercise of stock options | shares |  |  |  |  | 20,000 |  |
Common Stock |  |  |  |  |  |  |
Shareholders’ distributions |  |  |  | $ 1,686 | $ 1,498 |  |
Shares of common stock issued upon exercise of stock options | shares |  |  |  | 35,000 | 20,000 |  |
Exercise of stock options |  |  |  | $ 40 | $ (47) |  |
Warrants |  |  |  |  |  |  |
Number of common share per warrant | shares |  | 1 |  |  |  |  |
Price per common share for each warrant | $ / shares |  | $ 2.70 |  |  |  |  |
Flow Through Common Shares |  |  |  |  |  |  |
Flow-through share premium | $ 1,600 |  |  |  |  |  |
Number of units issued | shares | 4,000,000 |  |  |  |  |  |
Net proceeds | $ 10,000 |  |  | $ 1,200 |  | $ 12.9 | $ 10,000
Lexam |  |  |  |  |  |  |
Ratio of Company's share for acquired company's share |  |  | 0.056% |  |  |  |
Lexam | Warrants |  |  |  |  |  |  |
Number of units issued | shares |  |  | 12,687,035 |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 100.00% |  |  |  |

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