Note 11 - Borrowings (Tables)
 12 Months Ended
Dec. 31, 2015
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments [Table Text Block]

Consolidated Leverage Ratio

  

Adjusted LIBOR Rate Loans and Letter of

Credit Fee

    

Base Rate

Loans

    

Commitment

Fee

  

 

   < 1.00:1.0     1.25 %     0.25 %     0.15 %

≥ 1.00:1.0

and

< 1.50:1.0

     1.50 %     0.50 %     0.20 %

≥ 1.50:1.0

and

< 2.00:1.0

     1.75 %     0.75 %     0.25 %

≥ 2.00:1.0

and

< 2.50:1.0

     2.00 %     1.00 %     0.30 %

 ≥ 2.50:1.0

         2.25 %     1.25 %     0.35 %