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v3.19.3.a.u2

Shares - Common shares (Details) - CAD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |
Beginning balance, outstanding (in shares) | 25,004,205 | 25,452,224
Issued upon exercise of stock options (in shares) | 327,000 | 297,940
Issued upon conversion of convertible debentures (in shares) | 87,096 | 2,211
Purchase of treasury shares for settlement of certain equity classified stock-based compensation (in shares) | (735,857) | (660,620)
Settlement of certain equity classified stock-based compensation (in shares) | 1,095,001 | 1,193,935
Retired through share purchase programs (in shares) |  | (1,281,485)
Ending balance, outstanding (in shares) | 25,777,445 | 25,004,205
Shares to satisfy recipient tax withholding requirements (in shares) | 513,540,000 | 553,036,000
Satisfaction of recipient tax withholding | $ 7,246 | $ 4,308
Common shares |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |
Beginning balance, outstanding (in shares) | 27,088,816 | 28,070,150
Issued upon exercise of stock options (in shares) | 327,000 | 297,940
Issued upon conversion of convertible debentures (in shares) | 87,096 | 2,211
Purchase of treasury shares for settlement of certain equity classified stock-based compensation (in shares) | 0 | 0
Settlement of certain equity classified stock-based compensation (in shares) | 0 | 0
Retired through share purchase programs (in shares) |  | (1,281,485)
Ending balance, outstanding (in shares) | 27,502,912 | 27,088,816
Treasury shares |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |
Beginning balance, outstanding (in shares) | (2,084,611) | (2,617,926)
Issued upon exercise of stock options (in shares) | 0 | 0
Issued upon conversion of convertible debentures (in shares) | 0 | 0
Purchase of treasury shares for settlement of certain equity classified stock-based compensation (in shares) | (735,857) | (660,620)
Settlement of certain equity classified stock-based compensation (in shares) | 1,095,001 | 1,193,935
Retired through share purchase programs (in shares) |  | 0
Ending balance, outstanding (in shares) | (1,725,467) | (2,084,611)

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