Note 11 - Stock-based Compensation - SARs Activity (Details) - Stock Appreciation Rights (SARs) [Member] $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
	Jul. 31, 2020 USD ($) $ / shares shares
Outstanding (in shares) | shares	1,349
Outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 24.86
Exercised (in shares) | shares	(201)
Exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 12.92
Outstanding (in shares) | shares	1,148
Outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 26.96
Outstanding, weighted average remaining contractual term (Year)	3 years 3 months 18 days
Outstanding, aggregate intrinsic value | $	$ 15,697
Vested and exercisable (in shares) | shares	1,005	[1]
Vested and exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 24.23
Vested and exercisable, weighted average remaining contractual term (Year)	3 years 1 month 6 days
Vested and exercisable, aggregate intrinsic value | $	$ 15,323

[1] The number of SARs vested and exercisable at January 31, 2019 includes 877,500 Class A and 127,500 Class B shares previously held by Mr. Karl Lopker which will expire on August 25, 2019 if not exercised by his estate. Exercise prices for these SARs range from $10.50 to $31.65.