Note 15 - Stock-based Compensation Plan (Details Textual) - USD ($)
 3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 29, 2016
Jun. 23, 2016
Feb. 25, 2016
Jan. 21, 2015
May 01, 2008
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
May 07, 2015
Allocated Share-based Compensation Expense                             $ 548,000 $ 413,000 $ 295,000  
Earnings Per Share, Basic             $ 0.16 $ 0.16 $ 0.19 $ 0.13 $ 0.18 $ 0.13 $ 0.10 $ 0.12 $ 0.64 $ 0.53 $ 0.33  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 60,200           60,200               60,200      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price $ 15.33           $ 15.33               $ 15.33      
Stock Appreciation Rights (SARs) [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted                             105,500 128,000 110,000  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period                             105,500      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period                             8,839      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period                             106,004      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value $ 2.93           $ 2.93       $ 2.76       $ 2.93 $ 2.76    
Restricted Stock [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period                             6,000 8,500 6,000  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period                             1,000  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period                             6,250 6,000 31,000  
Allocated Share-based Compensation Expense                             $ 50,000 $ 37,000 $ 37,000  
Restricted Stock Units (RSUs) [Member]                                    
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options $ 201,000           $ 201,000               $ 201,000      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       35,000                     30,000      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period                             5,000      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period                             35,000      
Allocated Share-based Compensation Expense                             $ 186,000 $ 116,000    
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period       2 years                            
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value $ 8.26           $ 8.26               $ 8.26      
Stock Granted, Value, Share-based Compensation, Net of Forfeitures                             $ 289,000      
Restricted Stock Units (RSUs) [Member] | Executive Officer [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period         25,000                   21,500      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period                             3,500      
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period         2 years                          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value $ 4.94           $ 4.94               $ 4.94      
Stock Granted, Value, Share-based Compensation, Net of Forfeitures                             $ 124,000      
Restricted Stock Units (RSUs) [Member] | Executive Officer [Member] | Contingent Vesting Achievement [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period         25,000                          
Earnings Per Share, Basic         $ 0.80                          
Stock Incentive Plan 2008 [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee           1,000,000                        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized                                   1,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized for Year Grants to Individuals                                   100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 424,659           424,659               424,659      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period                             334,878      
Stock Incentive Plan 2008 [Member] | Stock Appreciation Rights (SARs) [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term                             7 years 7 years 7 years  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate                             41.21% 56.42% 60.11%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate                             1.47% 1.79% 2.27%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate                             1.50% 1.30% 0.00%  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit                             $ 1.52      
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit                             $ 8.53      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options $ 319,000           $ 319,000               $ 319,000      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition                             1 year 229 days      
Stock Incentive Plan 2008 [Member] | Stock Appreciation Rights (SARs) [Member] | Certain Officers [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted       105,500                            
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period       10 years                            
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period       3 years                            
Stock Incentive Plan 2008 [Member] | Restricted Stock [Member]                                    
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options $ 4,000           $ 4,000       $ 13,000       $ 4,000 $ 13,000 $ 0  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       6,000                            
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period     1,000                              
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period 4,000 1,000