Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 17.9	$ 4.0
Common stock, authorized (in shares)	36,000	36,000
Common stock, outstanding (in shares)	26,883	21,958
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001

Amount of allowance for credit loss on accounts receivable.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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