Capital Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Stock options exercised (shares)	118,437	5,333
Weighted average exercise price of stock options exercised (usd per share)	$ 10.33	$ 7.31
Proceeds from exercises of stock options	$ 1,223	$ 39

Number of share options (or share units) exercised during the current period.

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Balance Type:	na
Period Type:	duration