Share Capital - Share-based Payment Arrangement, Option, Activity (Detail)	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2020 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Balance | shares	3,839,017	1,677,192
Number of Share, Granted | shares	2,604,511
Number of Shares, Exercised | shares	(165,872)
Number of Shares, Forfeited | shares	(613,250)
Number of Share, Vested | shares	1,749,365
Number of Shares, Ending Balance | shares	5,664,406	3,839,017
Number of Share, Exercisable | shares	1,532,282
Weighted Average Exercise Price, Balance | $ / shares	$ 13.21
Weighted Average Exercise Price, Granted | $ / shares	10.36
Weighted Average Exercise Price, Exercised | $ / shares	12.72
Weighted Average Exercise Price, Forfeited | $ / shares	13.27
Weighted Average Exercise Price, Vested | $ / shares	13.37
Weighted Average Exercise Price, Ending Balance | $ / shares	$ 11.91	$ 13.21
Weighted Average Exercise Price, Exercisable | $ / shares			$ 13.22
Weighted Average Contractual Life, Balance	4 years 4 months 20 days	5 years 6 months 25 days
Weighted Average Contractual Life, Exercisable	5 years 25 days
Aggregate Intrinsic Value, Balance | $	$ 85,408,034	$ 218,234
Aggregate Intrinsic Value, Exercisable | $	$ 21,590,351