Note 2 - Revenue 1 (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2019	Jan. 31, 2020
Contract with Customer, Liability, Revenue Recognized			$ 83,700
Revenue, Remaining Performance Obligation, Amount	$ 282,300		282,300
Capitalized Contract Cost, Amortization			2,391	$ 2,161
Capitalized Contract Cost, Impairment Loss			$ 0	0
Direct Costs of Obtaining Contract [Member]
Capitalized Contract Cost, Amortization Period (Year)	5 years		5 years
Capitalized Contract Cost, Net, Total	$ 12,200		$ 12,200			$ 12,300
Direct Costs of Obtaining Contract [Member] | Selling and Marketing Expense [Member]
Capitalized Contract Cost, Amortization	$ 1,100	$ 900	$ 2,100	$ 1,900
Costs to Fulfill Contract [Member]
Capitalized Contract Cost, Amortization Period (Year)	5 years		5 years			5 years
Capitalized Contract Cost, Net, Total	$ 1,400		$ 1,400			$ 1,400
Costs to Fulfill Contract [Member] | Cost of Sales [Member]
Capitalized Contract Cost, Amortization	$ 200	$ 100	$ 300		$ 300