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INCOME TAXES - Schedule of Capital Losses and Net Operating Losses (Details) $ in Thousands | Dec. 31, 2020 USD ($)
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Operating Loss Carryforwards [Line Items] |
Net operating losses expected to expire | $ 75,000
CANADA | Non-capital losses | Canada |
Operating Loss Carryforwards [Line Items] |
Amount | 42,853
CANADA | Capital losses | Canada |
Operating Loss Carryforwards [Line Items] |
Amount | 3,180
CANADA | Investment tax credits | Canada |
Operating Loss Carryforwards [Line Items] |
Amount | 1,172
Pre-2018 net operating losses | UNITED STATES | United States |
Operating Loss Carryforwards [Line Items] |
Amount | 292,139
Post-2017 net operating losses | UNITED STATES | United States |
Operating Loss Carryforwards [Line Items] |
Amount | $ 23,726

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