General form of registration statement for all companies including face-amount certificate companies

Summary of Significant Accounting Policies - Disaggregated revenue (Details)

v3.21.2
Summary of Significant Accounting Policies - Disaggregated revenue (Details) - Evolv Technologies Holdings Inc [Member] - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2019
Disaggregation of Revenue [Line Items]        
Total revenue $ 3,999 $ 640 $ 4,785 $ 5,846
Maintenance revenue included in subscription revenue 300 100 600 300
Product revenue        
Disaggregation of Revenue [Line Items]        
Total revenue 2,502 56 1,279 4,192
Subscription revenue        
Disaggregation of Revenue [Line Items]        
Total revenue 1,300 459 2,637 1,096
Service revenue        
Disaggregation of Revenue [Line Items]        
Total revenue 197 125 869 558
Service revenue        
Disaggregation of Revenue [Line Items]        
Total revenue 65 5    
Maintenance revenue        
Disaggregation of Revenue [Line Items]        
Total revenue $ 132 $ 120 $ 519 $ 422