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Note 14 - Stockholders' Equity (Details Textual) - USD ($) |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
May 09, 2016 | Jan. 02, 2015 | May 31, 2015 | Aug. 31, 2010 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Oct. 31, 2008
Stock Repurchase Program, Authorized Amount |  |  |  | $ 10,000,000 |  |  |  | $ 5,000,000
Stock Repurchase Program Additional Authorized Amount |  |  |  | $ 5,000,000 |  |  |  |
Treasury Stock, Shares, Acquired |  |  |  |  | 0 | 0 |  |
Stock Repurchased and Retired During Period, Shares |  |  |  |  | 18,229 | 96,076 |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized |  |  |  |  | $ 2,200,000 |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  |  |  |  | 1 year 182 days |  |  |
Allocated Share-based Compensation Expense |  |  |  |  | $ 1,800,000 | $ 1,200,000 | $ 800,000 |
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures |  |  |  |  | 0 | 119,343 | 0 |
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures |  |  |  |  | $ 0 | $ 500,000 | $ 0 |
Proceeds from Issuance of Common Stock |  |  |  |  | $ 19,142,000 |  | $ 14,046,000 |
Treasury Stock, Shares |  |  |  |  | 0 | 0 |  |
D.A. Davidson and Co. [Member] |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues | 5,175,000 |  |  |  |  |  |  |
Share Price | $ 4 |  |  |  |  |  |  |
Share Price, Net | $ 3.77 |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock | $ 19,100,000 |  |  |  |  |  |  |
Chief Executive Officer [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  | 600,000 |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 79,240 | 978,526 | 61,957 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  |  |  | $ 4.36 | $ 4.53 | $ 9.05 |
Allocated Share-based Compensation Expense |  |  |  |  | $ 250,000 | $ 250,000 | $ 350,000 |
Restricted Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  |  |  |  | 3 years |  |  |
Restricted Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  |  |  |  | 5 years |  |  |
Restricted Stock [Member] | Key Employees [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 20,000 | 917,851 | 18,536 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  |  |  | $ 4.78 | $ 4.55 | $ 11.38 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized |  |  |  |  | $ 100,000 | $ 4,400,000 | $ 200,000 |
Performance Shares [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 64,159 | 10,000 | 7,500 |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures and Expirations |  |  |  |  | 1,875 | 13,750 |  |
Allocated Share-based Compensation Expense |  |  |  |  | $ 100,000 |  |  |
Plan 2001 [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  | 10 years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  | 1,900,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant |  |  |  |  | 555,785 |  |  |
Long-term Incentive Plan [Member] |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  | $ 1,200,000 |  |
Percentage of Incentive Plan Based on Service Completion |  | 50.00% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period |  | 3 years |  |  |  |  |  |
Percentage of Incentive Plan Based on Shareholder Return |  | 50.00% |  |  |  |  |  |
Incentive Plan, Term for ShareholderReturn |  | 3 years |  |  |  |  |  |
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures |  |  |  |  |  | 86,483 |  |
Stock Issued During Period, Shares, Restricted Stock Award, Forfeited |  |  |  |  | 0 | 54,519 |  |

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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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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