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Note 4 - Fair Value Measurements (Details) (USD $) | Mar. 31, 2014 | Dec. 31, 2013
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Note 4 - Fair Value Measurements (Details) [Line Items] |  |
Available-for-sale Securities, Current | $ 155,940,000 | $ 157,143,000
Fair Value, Inputs, Level 3 [Member] |  |
Note 4 - Fair Value Measurements (Details) [Line Items] |  |
Available-for-sale Securities, Current | $ 0 | $ 0

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- Definition Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 + Details
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