Note 1 - Summary of Significant Accounting Policies - Disaggregation of Revenue by Type (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Revenues	$ 71,679	$ 65,896	$ 75,436	$ 96,204	$ 74,286	$ 59,915	$ 69,936	$ 79,988	$ 309,215	$ 284,125	$ 283,419
Revenues, percentage									100.00%	100.00%	100.00%
Revenues, variance									$ 25,090	$ 706
Revenues, variance, percentage									8.80%	0.20%
Internet [Member]
Revenues									$ 259,404	$ 238,054	$ 240,034
Revenues, percentage									83.90%	83.80%	84.70%
Revenues, variance									$ 21,350	$ (1,980)
Revenues, variance, percentage									9.00%	(0.80%)
Contact Center [Member]
Revenues									$ 49,811	$ 46,071	$ 43,385
Revenues, percentage									16.10%	16.20%	15.30%
Revenues, variance									$ 3,740	$ 2,686
Revenues, variance, percentage									8.10%	6.20%
Reorder Customer [Member]
Revenues									$ 272,648	$ 248,560	$ 241,780
Revenues, percentage									88.20%	87.50%	85.30%
Revenues, variance									$ 24,088	$ 6,780
Revenues, variance, percentage									9.70%	2.80%
New Order Customer [Member]
Revenues									$ 36,567	$ 35,565	$ 41,639
Revenues, percentage									11.80%	12.50%	14.70%
Revenues, variance									$ 1,002	$ (6,074)
Revenues, variance, percentage									2.80%	(14.60%)