Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$ 0.9	$ 0.5
Common stock, par value	$ 0.00000625	$ 0.00000625
Common stock, shares authorized	2,020,500,000	2,020,500,000
Common stock, shares outstanding	1,100,200,000	1,081,600,000