Note 11 - Stock-based Compensation (Details Textual)	3 Months Ended
	Apr. 30, 2020 USD ($) shares
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation (in shares) | shares	2,000
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 93,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 17,800,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 182 days
Performance Shares [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 100,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	73 days
Share-based Payment Arrangement, Expense (Reversal of Expense)	$ (90,000)
Share-based Payment Arrangement, Reversal of Expense	$ 300,000
Stock Appreciation Rights (SARs) [Member]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation (in shares) | shares	200
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 11,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 2,200,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 328 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 28,000