The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 1,574								$ 1,574
Revenue from Contract with Customer, Including Assessed Tax		28,844	$ 19,786	$ 17,277	$ 11,567	$ 10,053	$ 8,572	$ 8,510	$ 3,632	77,474	$ 30,767	$ 1,279
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance		25,503				9,319				25,503	9,319
Cost of Goods and Services Sold, Total		11,572	$ 7,576	$ 5,231	$ 3,133	$ 1,338	$ 1,051	$ 1,013	$ 1,186	27,512	$ 4,588	$ 35
Accounting Standards Update 2014-09 [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,900
Cost of Goods and Services Sold, Total	200
Accounting Standards Update 2014-09 [Member] \| Product Sales Allowance [Member]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance	1,100
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 1,574								$ 1,574
Retained Earnings [Member] \| Accounting Standards Update 2014-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 1,600