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

Stock Based Compensation - Stock based compensation expenses by award type (Details)

v3.21.2
Stock Based Compensation - Stock based compensation expenses by award type (Details) - Evolv Technologies Holdings, Inc. - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]            
Share-based Payment Arrangement, Expense $ 535 $ 60 $ 1,617 $ 122 $ 662 $ 264
Options to purchase common stock            
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]            
Share-based Payment Arrangement, Expense 264 $ 60 467 $ 122 $ 100  
Warrants to purchase common stock            
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]            
Share-based Payment Arrangement, Expense 197   1,004      
Unvested restricted stock units            
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]            
Share-based Payment Arrangement, Expense $ 74   $ 146