Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Allowances for Accounts Receivable (in dollars)	$ 9,055	$ 11,066	$ 13,159
Preferred stock-issued	0	0	0
Common Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001	$ 0.0001
Common stock, shares authorized	245,000,000	245,000,000	135,000,000
Common stock, shares issued	133,159,000	132,754,000	132,530,000
Common stock, shares outstanding	83,046,000	83,520,000	85,729,000
Treasury stock-shares at cost	50,113,000	49,234,000	46,801,000
Preferred Class A [Member]
Preferred stock-par value	$ 0.0001	$ 0.0001	$ 0.0001
Preferred stock- shares authorized	5,000,000	5,000,000	5,000,000
Preferred Class B [Member]
Preferred stock-par value	$ 0.0001	$ 0.0001	$ 0.0001
Preferred stock- shares authorized	60,000	60,000	60,000

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

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