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

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Note 2 - Revenue Recognition (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Revenue from Contract with Customer, Including Assessed Tax	$ 77,877	$ 87,507	$ 72,653
Capitalized Contract Cost, Net, Total	223
Contract with Customer, Liability, Revenue Recognized	3,728
Accounting Standards Update 2014-09 [Member]
Revenue from Contract with Customer, Including Assessed Tax	4,078
Unbilled Receivables, Current	8,597
Capitalized Contract Cost, Net, Total				$ 239
Capitalized Contract Cost, Amortization	120
Capitalized Contract Cost, Impairment Loss	$ 0
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				$ 8,555