XML 35 R24.htm IDEA: XBRL DOCUMENT v3.21.1
Revenue Recognition (Narrative) (Details) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Revenue from Contract with Customer [Abstract]    
Primary term of contract 5 years  
Revenue recognized in contract liability $ 200,000 $ 200,000
Contract assets recognized $ 0