STOCK-BASED COMPENSATION - Summary of PSUs, DSUs and RSUs Granted, Exercised, Forfeited and Expired (Detail) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Restricted Stock Units Time Based
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of units, Outstanding at the beginning	2,414,066
Granted	1,890,987
Forfeited	(5,588)
Number of units, Outstanding at the end	4,299,465
Restricted Share Units ("RSUs") Performance-Based [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of units, Outstanding at the beginning	200,000
Granted	878,601
Number of units, Outstanding at the end	1,078,601
Deferred Share Units ("DSUs") [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of units, Outstanding at the beginning	363,664	132,597
Granted	31,837	83,915
Number of units, Outstanding at the end	395,501	216,512
Performance Share Units ("PSUs") [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of units, Outstanding at the beginning	197,471	223,052
Forfeited		(25,581)
Number of units, Outstanding at the end	197,471	197,471