Note 3 - Computation of Net Incoe (Loss) Per Share - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Net income (loss)	$ 60	$ (13,250)	$ (350)	$ (16,484)
Dividends declared	(1,448)	(1,387)	(2,879)	(2,761)
Undistributed net loss	(1,388)	(14,637)	(3,229)	(19,245)
Dividends declared	1,448	1,387	2,879	2,761
Common Class A [Member]
Net income (loss)	52	(11,379)	(301)	(14,152)
Dividends declared	(1,249)	(1,191)	(2,481)	(2,370)
Undistributed net loss	(1,197)	(12,570)	(2,782)	(16,522)
Dividends declared	$ 1,249	$ 1,191	$ 2,481	$ 2,370
Weighted average shares of common stock outstanding—basic (in shares)	17,245	16,465	17,179	16,417
Weighted average potential shares of common stock (in shares)	568	0	0	0
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	17,813	16,465	17,179	16,417
Basic net loss per common share (in dollars per share)	$ 0.00	$ (0.69)	$ (0.02)	$ (0.86)
Diluted net loss per common share (in dollars per share)	0.00	(0.69)	(0.02)	(0.86)
Basic net (loss) income per share (in dollars per share)	0.00	(0.69)	(0.02)	(0.86)
Diluted net (loss) income per share (in dollars per share)	$ 0.00	$ (0.69)	$ (0.02)	$ (0.86)
Common Class B [Member]
Net income (loss)	$ 8	$ (1,871)	$ (49)	$ (2,332)
Dividends declared	(199)	(196)	(398)	(391)
Undistributed net loss	(191)	(2,067)	(447)	(2,723)
Dividends declared	$ 199	$ 196	$ 398	$ 391
Weighted average shares of common stock outstanding—basic (in shares)	3,321	3,264	3,321	3,264
Weighted average potential shares of common stock (in shares)	68	0	0	0
Weighted average shares of common stock and potential common shares outstanding—diluted (in shares)	3,389	3,264	3,321	3,264
Basic net loss per common share (in dollars per share)	$ 0.00	$ (0.57)	$ (0.01)	$ (0.71)
Diluted net loss per common share (in dollars per share)	0.00	(0.57)	(0.01)	(0.71)
Basic net (loss) income per share (in dollars per share)	0.00	(0.57)	(0.01)	(0.71)
Diluted net (loss) income per share (in dollars per share)	$ 0.00	$ (0.57)	$ (0.01)	$ (0.71)