Date when an entity was incorporated

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

Date the operations of the entity commenced, in CCYY-MM-DD format.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

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- Definition

Amount of net operating losses related to tax deduction for stock-based compensation in excess of book expenses, which was not recognized in deferred tax assets.

+ References

No definition available.

+ Details

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- Definition

The maturity period for short-term investments.

+ References

No definition available.

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- Definition

Represents the number of subsidiaries of equity method investees.

+ References

No definition available.

+ Details

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Note 1 - General (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended
Note 1 - General (Details Textual) $ in Thousands	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jan. 01, 2017 USD ($)	Dec. 31, 2016 USD ($)
Operations Commenced Date			Jan. 01, 2005
Subsidiary or Equity Method Investee, Number	7		7
Entity Incorporation, Date of Incorporation			Nov. 24, 2004
Gain (Loss) on Foreign Currency Fair Value Hedge Derivatives	$ 653	$ 154	$ 918	$ 82
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	$ 0
Short-term Investments [Member] \| US Treasury Securities [Member] \| Maximum [Member]
Short-term Investment, Maturity Period			1 year
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Net Operating Losses Related to Excess Tax Benefit						$ 7,131
State and Local Jurisdiction [Member]
Net Operating Losses Related to Excess Tax Benefit						$ 718
Retained Earnings [Member] \| Accounting Standards Update 2016-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption					$ (2,616)