Note 2 - Revenue From Contracts With Customers 1 (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Capitalized Contract Cost, Impairment Loss	$ 0	$ 0
Contract with Customer, Liability, Revenue Recognized	4,600	3,300
Revenue, Remaining Performance Obligation, Amount	68,500
Contract with Customer, Performance Obligation Satisfied in Previous Period	700	500
Capitalized Contract Cost, Amortization	124	105
Prepaid Expenses and Other Current Assets [Member]
Contract with Customer, Asset, Net, Current, Total		3,600
Capitalized Contract Cost, Net, Total	400		$ 800
Deferred Costs, Total		$ 300
Other Noncurrent Assets [Member]
Capitalized Contract Cost, Net, Total	$ 400
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member]
Concentration Risk, Percentage	100.00%	100.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| Non-US [Member]
Concentration Risk, Percentage	59.00%	55.00%

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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