Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 4,613	$ 7,500
Common Stock, par value (in dollars per share)	$ 0.25	$ 0.25
Common Stock, shares authorized (in shares)	360,000,000	360,000,000
Common Stock, shares issued (in shares)	110,834,088	110,834,088
Treasury stock, shares (in shares)	11,547,475	11,903,252

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

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