XML 146 R58.htm IDEA: XBRL DOCUMENT v3.21.2
Segment Reporting - Additional Information (Details)
$ in Millions
3 Months Ended 6 Months Ended 9 Months Ended
Sep. 30, 2021
USD ($)
Sep. 30, 2020
USD ($)
Apr. 14, 2020
Site
Sep. 30, 2021
USD ($)
Site
Segment
Sep. 30, 2020
USD ($)
Dec. 31, 2020
USD ($)
Segment Reporting [Abstract]            
Number of reportable segments | Segment       2    
Number of converted operated sites to dealer operated sites | Site     46 0    
Contract costs, unamortized balance $ 9.9     $ 9.9   $ 8.3
Contract costs, amortization against operating revenues $ 0.4 $ 0.3   $ 1.1 $ 0.9