Note 2 - Revenue Recognition - Disaggregation Of Revenue by Type (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Revenues	$ 87,390	$ 79,657
Revenues	100.00%	100.00%
Revenues	$ 7,733
Revenues	9.70%
Internet [Member]
Revenues	$ 74,320	$ 66,647
Revenues	85.00%	83.70%
Revenues	$ 7,673
Revenues	11.50%
Contact Center [Member]
Revenues	$ 13,070	$ 13,010
Revenues	15.00%	16.30%
Revenues	$ 60
Revenues	0.50%
Reorder Customer [Member]
Revenues	$ 71,501	$ 64,465
Revenues	81.80%	80.90%
Revenues	$ 7,036
Revenues	10.90%
New Order Customer [Member]
Revenues	$ 15,889	$ 15,192
Revenues	18.20%	19.10%
Revenues	$ 697
Revenues	4.60%

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration