Unaudited Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Statement of Cash Flows [Abstract]
Restricted cash	$ 0.2	$ 0.2	$ 0.2	$ 0.2