Note 3 - Computation of Net (Loss) Income Per Share - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Net (loss) income	$ (3,234)	$ 1,397
Dividends declared	(1,374)	(1,359)
Undistributed net (loss) income	(4,608)	38
Net (loss) income per share
Dividends declared	1,374	1,359
Undistributed net (loss) income	(4,608)	38
Net (loss) income	(3,234)	1,397
Common Class A [Member]
Net (loss) income	(2,774)	1,196
Dividends declared	(1,178)	(1,164)
Undistributed net (loss) income	(3,952)	32
Net (loss) income per share
Dividends declared	1,178	1,164
Undistributed net (loss) income	(3,952)	32
Net (loss) income	$ (2,774)	$ 1,196
Weighted average shares of common stock outstanding—basic (in shares)	16,367	16,076
Weighted average potential shares of common stock (in shares)		1,750
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	16,367	17,826
Basic net (loss) income per common share (in dollars per share)	$ (0.17)	$ 0.07
Diluted net (loss) income per common share (in dollars per share)	$ (0.17)	$ 0.07
Common Class B [Member]
Net (loss) income	$ (460)	$ 201
Dividends declared	(196)	(195)
Undistributed net (loss) income	(656)	6
Net (loss) income per share
Dividends declared	196	195
Undistributed net (loss) income	(656)	6
Net (loss) income	$ (460)	$ 201
Weighted average shares of common stock outstanding—basic (in shares)	3,264	3,232
Weighted average potential shares of common stock (in shares)		182
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	3,264	3,414
Basic net (loss) income per common share (in dollars per share)	$ (0.14)	$ 0.06
Diluted net (loss) income per common share (in dollars per share)	$ (0.14)	$ 0.06