Note 6 - Stock-based Compensation - PSUs Activity (Details) - Performance Shares [Member] - $ / shares shares in Thousands	12 Months Ended
	Jan. 31, 2021		Jan. 31, 2020
Restricted stock (in shares)	90		0
Restricted stock, weighted average grant date fair value (in dollars per share)	$ 39.82		$ 0
Granted (in shares)	93		93
Granted, weighted average grant date fair value (in dollars per share)	$ 40.54		$ 39.82
Released (in shares)	(21)	[1]	0
Released, weighted average grant date fair value (in dollars per share)	$ 39.82	[1]	$ 0
Forfeited (in shares)	(9)		(3)
Forfeited, weighted average grant date fair value (in dollars per share)	$ 39.82		$ 39.82
Restricted stock (in shares)	153		90
Restricted stock, weighted average grant date fair value (in dollars per share)	$ 40.26		$ 39.82

[1] The number of PSUs released includes shares withheld on behalf of employees to satisfy minimum statutory tax withholding requirements. During the fiscal year ended January 31, 2021, the Company withheld 8,000 shares for payment of these taxes. The value of the withheld shares for the fiscal year ended January 31, 2021 was $0.3 million.