Balance Sheet Parentheticals (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts Receivable, Allowance for Credit Loss, Current	$ 16,835	$ 15,469
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	125,000,000	125,000,000
Common Stock, Shares, Issued	44,786,011	44,786,011
Common Stock, Shares, Outstanding	24,609,232	24,921,963
Treasury Stock, Shares	20,176,779	19,864,048

Amount of allowance for credit loss on accounts receivable, classified as current.

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