Note 13 - Quarterly Information (Unaudited) - Schedule of Quarterly Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Total revenue	$ 82,706	$ 79,577	$ 84,543	$ 86,190	$ 80,753	$ 76,925	$ 75,958	$ 71,382	$ 333,016	$ 305,018	$ 277,973
Total costs and expenses	79,142	77,103	82,817	84,381	83,441	76,495	75,415	72,741	155,884	149,425	130,851
Gross margin	45,686	42,216	44,107	45,123	40,934	38,879	39,264	36,516	177,132	155,593	147,122
Operating income	3,564	2,474	1,726	1,809	(2,688)	430	543	(1,359)	9,573	(3,074)	3,364
Net income (loss)	$ 4,936	$ 2,982	$ 1,113	$ 1,397	$ (5,172)	$ (161)	$ (1,161)	$ (2,571)	10,428	(9,065)	(15,450)
Common Class A [Member]
Net income (loss)									$ 8,939	$ (7,762)	$ (13,211)
Basic net (loss) income per common share (in dollars per share)	$ 0.26	$ 0.16	$ 0.06	$ 0.07	$ (0.28)	$ (0.01)	$ (0.06)	$ (0.14)	$ 0.55	$ (0.49)	$ (0.84)
Diluted net (loss) income per common share (in dollars per share)	0.24	0.14	0.05	0.07	(0.28)	(0.01)	(0.06)	(0.14)	$ 0.50	$ (0.49)	$ (0.84)
Common Class B [Member]
Net income (loss)									$ 1,489	$ (1,303)	$ (2,239)
Basic net (loss) income per common share (in dollars per share)	0.22	0.13	0.05	0.06	(0.23)	(0.01)	(0.05)	(0.12)	$ 0.46	$ (0.41)	$ (0.70)
Diluted net (loss) income per common share (in dollars per share)	$ 0.21	$ 0.12	$ 0.05	$ 0.06	$ (0.23)	$ (0.01)	$ (0.05)	$ (0.12)	$ 0.44	$ (0.41)	$ (0.70)