The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Shareholders' Equity - Summary of Stock Options Granted (Detail) $ / shares in Units, $ / shares in Units, $ in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 CAD ($) $ / shares shares	Mar. 31, 2020 CAD ($) $ / shares shares	Dec. 31, 2019 CAD ($) $ / shares shares	Dec. 31, 2019 CAD ($) $ / shares shares	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Canadian Dollar Under the New Option Stock Plan
Number of Options
Beginning balance (in shares)	2,356,413	2,356,413
Granted (in shares)	320,400	320,400
Exercised (in shares)	(89,288)	(89,288)
Forfeited (in shares)	(30,505)	(30,505)
Ending balance (in shares)	2,557,020	2,557,020	2,356,413	2,356,413
Weighted Average Exercise Price
Beginning balance (in dollars per share) \| (per share)	$ 16.21	$ 12.46
Granted (in dollars per share) \| (per share)	48.70	35.65
Exercised (in dollars per share) \| (per share)	15.63	11.85
Forfeited (in dollars per share) \| (per share)	25.13	18.82
Ending balance (in dollars per share) \| (per share)	$ 20.20	$ 14.36	$ 16.21	$ 12.46
Weighted- Average Contractual Term (years)	6 years 10 months 13 days	6 years 10 months 13 days	6 years 8 months 12 days	6 years 8 months 12 days
Aggregate intrinsic value Outstanding	$ 77,253	$ 77,253	$ 101,404	$ 101,404	$ 54,431	$ 77,807
U.S Dollar Under the New Option Stock Plan
Number of Options
Beginning balance (in shares)	2,853,346	2,853,346
Granted (in shares)	800,800	800,800
Exercised (in shares)	(33,204)	(33,204)
Forfeited (in shares)	(71,431)	(71,431)
Ending balance (in shares)	3,549,511	3,549,511	2,853,346	2,853,346
Weighted Average Exercise Price
Beginning balance (in dollars per share) \| $ / shares		$ 15.85
Granted (in dollars per share) \| $ / shares		36.36
Exercised (in dollars per share) \| $ / shares		11.80
Forfeited (in dollars per share) \| $ / shares		13.58
Ending balance (in dollars per share) \| $ / shares		$ 20.56		$ 15.85
Weighted- Average Contractual Term (years)	8 years 9 months 3 days	8 years 9 months 3 days	8 years 7 months 28 days	8 years 7 months 28 days
Aggregate intrinsic value Outstanding \| $					$ 54,011	$ 84,481