Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Allowance For Bad Debt	$ 15,469	$ 15,549
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	24,921,963	25,541,393
Treasury shares	19,864,048	19,244,618

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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