Note L - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Treasury Stock, Shares, Acquired			803,762
Treasury Stock Acquired, Average Cost Per Share			$ 12.23
Treasury Stock, Value, Acquired, Cost Method	$ 3,958	$ 1,563	$ 9,827	$ 4,365
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	651,627		651,627
Stock Issued During Period, Shares, Employee Stock Purchase Plans and Exercise of Share-based Awards			703,000