Note 26 - Reserve Roll Forwards - Valuation and Qualifying Accounts (Details) - Summary of Valuation and Qualifying Accounts - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Reserve for:      
Balance at January 1 $ 9,924 $ 10,640 $ 13,421
Charged to Cost and Expense 75 229 148
Deductions 4,964 945 2,929
Balance at December 31 $ 5,035 $ 9,924 $ 10,640
Doubtful Accounts and Returns [Member]      
Reserve for:      
Balance at January 1
Charged to Cost and Expense $ 37 $ 46  
Deductions $ 37 $ 46  
Balance at December 31
LIFO Inventory [Member]      
Reserve for:      
Balance at January 1 $ 8,342 $ 9,287 $ 12,201
Deductions 4,840 945 2,914
Balance at December 31 3,502 8,342 9,287
Inventory Valuation Reserve [Member]      
Reserve for:      
Balance at January 1 633 408 260
Charged to Cost and Expense   225 148
Deductions 87    
Balance at December 31 $ 546 $ 633 $ 408
Valuation Allowance of Deferred Tax Assets [Member]      
Reserve for:      
Balance at January 1
Balance at December 31
Aged and Obsoliete Supplies and Parts [Member]      
Reserve for:      
Balance at January 1 $ 949 $ 945 $ 960
Charged to Cost and Expense 38 4  
Deductions     15
Balance at December 31 $ 987 $ 949 $ 945