Note 3 - Revenue From Contracts With Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues	$ 21,914	$ 20,213	$ 63,023	$ 66,069
Percent of revenue	100.00%	100.00%	100.00%	100.00%
Transferred over Time [Member]
Percent of revenue	70.00%	59.00%	67.00%	66.00%
Transferred at Point in Time [Member]
Percent of revenue	30.00%	41.00%	33.00%	34.00%
License [Member]
Revenues	$ 6,454	$ 7,729	$ 20,360	$ 22,044
Service [Member]
Revenues	15,267	11,905	42,298	43,095
Product and Service, Other [Member]
Revenues	$ 193	$ 579	$ 365	$ 930

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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