XML 66 R49.htm IDEA: XBRL DOCUMENT v3.20.4
Equipment and Leasehold Improvements (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property, Plant and Equipment [Abstract]      
Depreciation and amortization expense $ 3.8 $ 3.7 $ 4.1