Note 2 - 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		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Net (loss) income	$ (161)	$ 1,533	$ (3,893)	$ (291)
Dividends declared	(1,345)	(1,328)	(4,021)	(3,970)
Undistributed net (loss) income	(1,506)	205	(7,914)	(4,261)
Net (loss) income per share
Dividends declared	1,345	1,328	4,021	3,970
Undistributed net (loss) income	(1,506)	205	(7,914)	(4,261)
Net (loss) income	(161)	1,533	(3,893)	(291)
Common Class A [Member]
Net (loss) income	(139)	1,311	(3,332)	(245)
Dividends declared	(1,152)	(1,136)	(3,442)	(3,393)
Undistributed net (loss) income	(1,291)	175	(6,774)	(3,638)
Net (loss) income per share
Dividends declared	1,152	1,136	3,442	3,393
Undistributed net (loss) income	(1,291)	175	(6,774)	(3,638)
Net (loss) income	$ (139)	$ 1,311	$ (3,332)	$ (245)
Weighted average shares of common stock outstanding—basic (in shares)	16,011	15,773	15,913	15,687
Weighted average potential shares of common stock (in shares)		829
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	16,011	16,602	15,913	15,687
Basic net (loss) income per common share (in dollars per share)	$ (0.01)	$ 0.08	$ (0.21)	$ (0.02)
Diluted net (loss) income per common share (in dollars per share)	$ (0.01)	$ 0.08	$ (0.21)	$ (0.02)
Common Class B [Member]
Net (loss) income	$ (22)	$ 222	$ (561)	$ (46)
Dividends declared	(193)	(192)	(579)	(577)
Undistributed net (loss) income	(215)	30	(1,140)	(623)
Net (loss) income per share
Dividends declared	193	192	579	577
Undistributed net (loss) income	(215)	30	(1,140)	(623)
Net (loss) income	$ (22)	$ 222	$ (561)	$ (46)
Weighted average shares of common stock outstanding—basic (in shares)	3,214	3,206	3,212	3,205
Weighted average potential shares of common stock (in shares)		95
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	3,214	3,301	3,212	3,205
Basic net (loss) income per common share (in dollars per share)	$ (0.01)	$ 0.07	$ (0.17)	$ (0.01)
Diluted net (loss) income per common share (in dollars per share)	$ (0.01)	$ 0.07	$ (0.17)	$ (0.01)