Represents the maximum maturity period for cash equivalents.

No definition available.

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- Definition

Represents the number of investment portfolios.

+ References

No definition available.

+ Details

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- Definition

Represents the number of securities held as trading securities.

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No definition available.

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Represents the number of variable interest entity.

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No definition available.

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- Definition

The amount of reclassification of tax effect from accumulated other comprehensive income.

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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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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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No definition available.

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands		12 Months Ended
	Feb. 12, 2018 shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Number of Variable Interest Entity		1
Maximum Maturity Period for Cash Equivalents		90 days
Number of Investment Portfolios		3
Number of Securities Held as Trading Securities		0	0
Unrecognized Tax Benefits		$ 0	$ 0
Number of Reportable Segments		2
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross \| shares		70,600	97,000
Reclassification of Tax Effects From AOCI
AOCI Attributable to Parent [Member]
Reclassification of Tax Effects From AOCI		(136)
Retained Earnings [Member]
Reclassification of Tax Effects From AOCI		136
ASU 2018-02 [Member] \| AOCI Attributable to Parent [Member]
Reclassification of Tax Effects From AOCI		(136)
ASU 2018-02 [Member] \| Retained Earnings [Member]
Reclassification of Tax Effects From AOCI		$ 136
Non Qualified Stock Options [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross \| shares	62,150
Restricted Stock [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted \| shares	5,520
Minimum [Member]
Property, Plant and Equipment, Useful Life		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life		40 years