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Share Capital (Other employee long-term incentives) (Details) - shares | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Restricted share units (RSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 1,410,192 | 1,404,325
Granted | 499,560 | 574,088
Conversion of Richmont units to Alamos units (note 5) | 112,774 |
Forfeiture | (171,452) | (257,345)
Settled | (350,140) | (310,876)
Shares outstanding | 1,500,934 | 1,410,192
Stock appreciation rights (SAR) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 1,489,575 | 2,471,462
Granted | 0 | 0
Conversion of Richmont units to Alamos units (note 5) | 0 |
Forfeiture | (316,074) | (729,816)
Settled | (117,976) | (252,071)
Shares outstanding | 1,055,525 | 1,489,575
Deferred share units (DSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 378,345 | 276,930
Granted | 102,260 | 130,009
Conversion of Richmont units to Alamos units (note 5) | 0 |
Forfeiture | 0 | (15,313)
Settled | 0 | (13,281)
Shares outstanding | 480,605 | 378,345
Performance share units (PSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 424,253 | 273,363
Granted | 269,780 | 340,188
Conversion of Richmont units to Alamos units (note 5) | 0 |
Forfeiture | (65,451) | (102,156)
Settled | (28,877) | (87,142)
Shares outstanding | 599,705 | 424,253

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