Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	1 Months Ended	12 Months Ended
Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Deferred Offering Costs, Expensed During Period	$ 3,100
Federal Income Tax Expense (Benefit), Continuing Operations		$ 0
Unrecognized Tax Benefits		0	$ 0
Provision for Doubtful Accounts		0	$ 0
State and Local Income Tax Expense (Benefit), Continuing Operations		$ 0
Number of Operating Segments		1
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Number of Major Customers		4	2
Concentration Risk, Percentage		77.00%	93.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Number of Major Customers		4	2
Concentration Risk, Percentage		71.00%	28.00%
Minimum [Member]
Property, Plant and Equipment, Useful Life		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life		30 years

The amount of deferred offering costs expensed during the reporting period.

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Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

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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 of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amount of state and local current and deferred income tax expense (benefit) attributable to continuing operations.

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Amount of unrecognized tax benefits.

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