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Share Capital (Antidilutive Securities) (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Earnings per share [line items]
Share price (cad per share)	$ 10.87	$ 7.18
Stock options
Earnings per share [line items]
Antidilutive securities	0	1,420

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- Definition

Antidilutive Securities Excluded From Computation Of Earnings Per Share, Amount1

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- Definition

Share Price1

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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