Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Allowance For Bad Debt	$ 18,625	$ 17,009
Preferred stock - par value per share	$ 0.01	$ 0.01
Preferred stock - authorized shares	10,000,000	10,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common stock - authorized shares	125,000,000	125,000,000
Common stock - issued shares	44,786,011	44,786,011
Common stock - outstanding shares	23,471,841	24,125,317
Treasury shares	21,314,170	20,660,694

Amount of allowance for credit loss on accounts receivable.

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