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Share Capital (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Equity Financing [Line Items] |  |
Stock Repurchased Authorization | 35,145,504 |
Repurchased Shares Price Per Share | $ 4.89 | $ 4.17
Other (loss) gain (note 12) | $ (3.7) | $ 5.1
Share capital [Member] |  |
Equity Financing [Line Items] |  |
Shares repurchased and cancelled (in shares) | 1,133,561 | 2,748,352
Expected cash outflow on redemption or repurchase of puttable financial instruments | $ 5.5 | $ 10.7
Other (loss) gain (note 12) |  | 5.2
Dividend reinvestment plan and share purchase plan (in shares) | 1,186,205 |
Dividend reinvestment plan and share purchase plan (ii) | $ 10.0 |
Shares Repurchased |  | $ 11.4
Share capital [Member] | Employee Share Purchase Plan [Member] |  |
Equity Financing [Line Items] |  |
Dividend reinvestment plan and share purchase plan (ii) | $ 8.3 |

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