Note O - Severance Expense (Details Textual)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2016
USD ($)
Sep. 30, 2016
USD ($)
Jun. 30, 2016
USD ($)
Mar. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Sep. 30, 2015
USD ($)
Jun. 30, 2015
USD ($)
Mar. 31, 2015
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Restructuring and Related Cost, Number of Positions Eliminated                 3    
Restructuring Charges $ 3,010      
Allocated Share-based Compensation Expense                 $ 6,600 $ 2,369 $ 214
Severance Expense [Member]                      
Allocated Share-based Compensation Expense                 1,910
Employee Severance [Member] | Accounts Payable and Accrued Liabilities [Member]                      
Restructuring Reserve $ 600               600    
Employee Severance [Member] | Severance Expense [Member]                      
Restructuring Charges                 1,100    
Allocated Share-based Compensation Expense                 $ 1,900