Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Allowance for doubtful accounts	$ 18.3	$ 21.3
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock authorized (in shares)	2,000,000,000	2,000,000,000
Common stock issued (in shares)	544,003,038	544,003,038
Common stock outstanding (in shares)	158,257,098	161,651,639
Treasury stock (in shares)	385,745,940	382,351,399

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

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