Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable, current	$ 9.9	$ 5.5
Convertible preferred stock - par value (in USD per share)	$ 0.00001	$ 0.00001
Convertible preferred stock - shares authorized (in shares)	10,000,000.0	10,000,000.0
Convertible preferred stock - issued (in shares)	0	0
Convertible preferred stock - outstanding (in shares)	0	0
Common stock - par value (in USD per share)	$ 0.00001	$ 0.00001
Common stock - shares authorized (in shares)	1,000,000,000.0	1,000,000,000.0
Common stock - shares issued (in shares)	327,700,000	335,900,000
Common stock - outstanding (in shares)	327,700,000	335,900,000

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

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