XML 168 R55.htm IDEA: XBRL DOCUMENT v3.21.2
Stock-Based Compensation - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Share-based Payment Arrangement [Abstract]          
Stock-based compensation benefit $ 1.2        
Stock-based compensation expense (income)   $ 4.7 $ 1.4 $ (2.8)  
Stock-based compensation liability $ 14.0   $ 14.0   $ 14.4