Interim Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Trade and other receivables, expected credit losses	$ 588	$ 588
Common shares, authorized	Unlimited	Unlimited
Common shares, no par value	$ 0	$ 0
Common shares, shares issued	84,681,364	84,681,364
Common shares, shares outstanding	84,681,364	84,681,364

Amount of allowance for credit loss on accounts receivable, classified as current.

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Face amount per share of no-par value common stock.

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Indicates that the number of common shares permitted to be issued by an entity's charter and bylaws is unlimited. The acceptable value is "Unlimited".

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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