CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Allowance for doubtful accounts	$ 5,310	$ 1,200
Preferred Stock, Shares Authorized	5,000,000
Preferred Stock, Shares Outstanding	135,000
Common stock, par value	$ 1.50	$ 1.50
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	24,934,981	24,934,981
Common stock, shares outstanding	24,934,981	24,934,981
Treasury stock, shares	4,475,489	4,588,084
Convertible Series A Preferred Stock
Preferred Stock, Par value	$ 0.01
Preferred Stock, Shares Authorized	180,000
Preferred Stock, Shares Issued	135,000
Preferred Stock, Shares Outstanding	135,000