Maximum value of common stock offered for sale under the sales agreement.

No definition available.

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 5
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Balance Type:	na
Period Type:	duration

- Definition

Amount recognized for uncertainty in income taxes classified as current.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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-SubTopic 10
-Section 50
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Period Type:	duration

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of new stock issued during the period.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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Note 2 - Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 27, 2014 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period \| shares		97,521
Proceeds from Issuance Initial Public Offering				$ 62,485
Payments of Stock Issuance Costs				452
Sale of Stock, Maximum Value of Stock Offered		$ 40,000
Number of Operating Segments		1
Number of Reportable Segments		1
Revenues				2,948
Available-for-sale Securities, Gross Realized Gain (Loss)		0	0	0
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities		0	0	$ 0
Liability for Uncertainty in Income Taxes, Current		$ 0	$ 0
IPO [Member]
Stock Issued During Period, Shares, New Issues \| shares	7,026,500
Share Price \| $ / shares	$ 10
Proceeds from Issuance Initial Public Offering	$ 62,500
Payments of Stock Issuance Costs	$ 7,800
Conversion of Stock, Shares Converted \| shares	8,651,805
IPO [Member] \| Underwriters [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period \| shares	916,500