Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands, shares in Millions	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowances	$ 18,797	$ 20,477
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock issued (shares)	104.0	103.0
Common shares outstanding (shares)	68.2	73.3
Treasury stock (shares)	35.8	29.7

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

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Face amount or stated value per share of common stock.

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