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Note 11 - Share-based Compensation (Tables)

3 Months Ended

Feb. 28, 2021

Notes Tables

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

		Three months ended
		February 28,				February 29,
		2021				2020
Stock options		$	1,193			$	1,068
Performance share unit plan			796				644
Deferred share unit plan			53				49
		$	2,042			$	1,761

Share-based Payment Arrangement, Option, Activity [Table Text Block]

		Number of stock options (thousands)				Weighted- average exercise price per share				Weighted- average remaining contractual term (years)				Aggregate intrinsic value
November 30, 2020			10,403			$	4.59
Granted			1,218				9.96
Exercised			(557	)			3.90
February 28, 2021			11,064			$	5.23				2.43			$	36,884
Vested and exercisable as of February 28, 2021			7,620			$	4.31				1.80			$	30,818

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

		Three months ended
		February 28,				February 29,
		2021				2020
Weighted-average assumptions used to value stock option awards:
Expected volatility			47.3	%			46.0	%
Expected term of options (years)			4				4
Expected dividend rate			—				—
Risk-free interest rate			0.3	%			1.6	%
Expected forfeiture rate			3.0	%			3.1	%
Weighted-average grant-date fair value		$	3.66			$	2.60
Intrinsic value of options exercised		$	3,505			$	4,879
Cash received from options exercised		$	—			$	—

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

		Number of PSU awards (thousands)				Weighted- average grant day fair value per award				Aggregate intrinsic value
November 30, 2020			1,684			$	4.59
Granted			331				10.07
Vested			(648	)			3.85
Performance adjustment			216				3.85
February 28, 2021			1,583			$	5.94			$	16,906

Other PSU-related Information [Table Text Block]

		Three months ended
		February 28,				February 29,
		2021				2020
Performance multiplier on PSUs vested			150	%			150	%
Common shares issued (thousands)			574				410
Total fair value of common shares issued		$	5,723			$	2,855
Withholding tax paid on PSUs vested		$	731			$	1,652

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