Note 2 - REVENUE FROM CONTRACTS WITH CUSTOMERS - 1 (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) item	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Number of Revenue Sources \| item			2
Capitalized Contract Cost, Impairment Loss	$ 0	$ 0	$ 0	$ 0
Contract with Customer, Liability, Noncurrent	1,700		1,700		$ 1,200
Contract with Customer, Liability, Revenue Recognized	6,500	5,900	10,500	7,700
Revenue, Remaining Performance Obligation, Amount	138,600		138,600
Contract with Customer, Performance Obligation Satisfied in Previous Period	(400)	(500)	100	600
Capitalized Contract Cost, Amortization	200	$ 100	327	$ 234
Prepaid Expenses and Other Current Assets [Member]
Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total	2,100		2,100		3,700
Capitalized Contract Cost, Net, Total	800		800		800
Other Noncurrent Assets [Member]
Capitalized Contract Cost, Net, Total	$ 1,600		$ 1,600		$ 900
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member]
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| Non-US [Member]
Concentration Risk, Percentage	56.00%	54.00%	60.00%	56.00%

Represents information pertaining to number of sources where the company is deriving revenue.

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

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

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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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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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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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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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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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