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Note 15 - Benefit Plans (Details) - USD ($) $ in Millions |  |  | 12 Months Ended
--- | --- | --- | ---
Jan. 01, 2014 | Jan. 01, 2013 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Note 15 - Benefit Plans (Details) [Line Items] |  |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 4.25% | 4.00% |  |  |
Defined Contribution Plan, Cost Recognized |  |  | $ 1.2 | $ 0.9 | $ 0.5
Deferred Compensation Liability, Current and Noncurrent |  |  | $ 3.9 | $ 3.7 |
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in Shares) |  |  | 2,058 | 1,150 |
Stock Purchase Plan [Member] |  |  |  |  |
Note 15 - Benefit Plans (Details) [Line Items] |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance (in Shares) |  |  | 250,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares) |  |  | 246,800 |  |
Maximum [Member] |  |  |  |  |
Note 15 - Benefit Plans (Details) [Line Items] |  |  |  |  |
Interest Expense, Deferred Compensation Plan |  |  | $ 0.1 | $ 0.1 | $ 0.1

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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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