XML 91 R58.htm IDEA: XBRL DOCUMENT v3.20.4
Defined Contribution Plan - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Retirement Benefits [Abstract]      
Contribution expenses $ 1.9 $ 1.6 $ 0.9