Represents warrant term against defects and workmanship.

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- Definition

Number of distributors with distribution agreements on a sell-through basis.

+ References

No definition available.

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- Definition

Represents percent of distributor sales.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Article 5

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Sum of the carrying amounts as of the balance sheet date of deferred costs capitalized at the end of the reporting period that are expected to be charged against earnings within one year or the normal operating cycle, if longer.

+ References

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Balance Type:	na
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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

No definition available.

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Note 1 - Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Available-for-sale Securities (in Dollars)	$ 177,919,000us-gaap_AvailableForSaleSecurities	$ 173,574,000us-gaap_AvailableForSaleSecurities
Deferred Compensation Plan Assets (in Dollars)	6,084,000us-gaap_DeferredCompensationPlanAssets	607,000us-gaap_DeferredCompensationPlanAssets
Deferred Compensation Liability, Current and Noncurrent (in Dollars)	6,200,000	600,000
Number Of Distributors Having Distribution Agreements	3
Auction Rate Securities [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Available-for-sale Securities (in Dollars)	5,400,000
Interest And Other Income [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Foreign Currency Transaction Gain (Loss), before Tax (in Dollars)	100,000	600,000	100,000
Building and Building Improvements [Member] \| Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	30 years
Building and Building Improvements [Member] \| Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Computer Equipment [Member] \| Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Computer Equipment [Member] \| Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	7 years
Transportation Equipment [Member] \| Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Transportation Equipment [Member] \| Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	15 years
Furniture and Fixtures [Member] \| Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Third Parties [Member] \| Sales Revenue, Goods, Net [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Percentof Distributor Sales	92.00%	91.00%
Small Distributors [Member] \| Sales Revenue, Goods, Net [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Percentof Distributor Sales	8.00%	9.00%
Three U.S. Distributors [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Deferred Revenue (in Dollars)	2,000,000	1,700,000
Deferred Costs, Current (in Dollars)	$ 200,000	$ 200,000
Know-How And Developed Technologies [Member] \| Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Know-How And Developed Technologies [Member] \| Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Land Use Rights [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	50 years
Patents [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Minimum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Extended Product Warranty Term	1 year
Maximum [Member]
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items]
Extended Product Warranty Term	2 years