Share Capital - Summary Of Weighted Average Grant Date Fair Value And Total Fair Value Of RSUs Vested (Detail) - Restricted Stock Units	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2020 $ / shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares
Weighted Average Grant Date Fair Value And Total Fair Value Of RSUs Vested [Line Items]
Weighted average grant date fair value (per share) of RSUs granted (CAD) \| $ / shares		$ 13.90		$ 11.70	$ 10.28
Total fair value of RSUs vested, using market price at vest date (USD) \| $	$ 9,076,673		$ 13,522,284

Weighted average grant date fair value and total fair value of rsus vested.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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