Note 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017	Jul. 31, 2018	Feb. 01, 2018	Jan. 31, 2018
Income Tax Expense (Benefit), Total	$ 597	$ 1,249	$ 3,251	$ 2,701
Effective Income Tax Rate Reconciliation, Percent, Total	17.00%	115.00%	37.00%	(227.00%)
Income Tax Expense, Transition Tax on Accumulated Foreign Earnings	$ 10,000
Transition Tax for Accumulated Foreign Earnings, Liability	700		$ 700		$ 2,000
Retained Earnings (Accumulated Deficit), Ending Balance	(52,047)		(52,047)			$ (53,434)	$ (75,559)
Unrecognized Tax Benefits, Ending Balance	1,200		1,200
Unrecognized Tax Benefits, Period Increase (Decrease), Total			(900)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	100		100
Deferred Tax Assets, Valuation Allowance, Total	35,400		$ 35,400				$ 33,700
Foreign Tax Authority [Member] | State Administration of Taxation, China [Member]
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$ 500
Accounting Standards Update 2016-16 [Member]
Retained Earnings (Accumulated Deficit), Ending Balance						9,584
Deferred Tax Assets, Net of Valuation Allowance, Total						$ 9,600