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

Long-term Debt - Silicon valley bank term loan (Details)

v3.21.2
Long-term Debt - Silicon valley bank term loan (Details) - Evolv Technologies Holdings Inc [Member]
3 Months Ended 12 Months Ended
Jul. 05, 2017
USD ($)
item
Mar. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
shares
Mar. 31, 2021
shares
Feb. 12, 2019
$ / shares
shares
May 08, 2018
USD ($)
Debt Instrument [Line Items]              
Number of monthly payments 36            
Warrants to purchase shares of common stock | shares   740,991 5,127,237 3,386,246 5,127,237    
Warrants exercise price | $ / shares   $ 0.15          
2017 SVB Term Loan              
Debt Instrument [Line Items]              
Face amount of debt $ 5,000,000 $ 3,100,000          
Number of monthly payments 36 36          
Interest rate       5.25%      
Warrants to purchase shares of common stock | shares           75,000  
Warrants exercise price | $ / shares           $ 0.09  
Accrued interest, current       $ 100,000      
Interest expense       $ 200,000      
Term Loan A Advance              
Debt Instrument [Line Items]              
Face amount of debt $ 4,000,000            
Term Loan B Advance              
Debt Instrument [Line Items]              
Face amount of debt 1,000,000           $ 1,000,000
Revolving line of credit outstanding              
Debt Instrument [Line Items]              
Face amount of debt 1,000,000 $ 7,000,000 $ 3,000,000        
Maximum borrowing capacity $ 1,000,000 $ 7,000,000 $ 10,000,000        
Wall Street Journal Prime Rate              
Debt Instrument [Line Items]              
Warrants to purchase shares of common stock | shares     1,000,000        
Warrants exercise price | $ / shares     $ 0.16        
Wall Street Journal Prime Rate | 2017 SVB Term Loan              
Debt Instrument [Line Items]              
Spread on variable rate 1.25%            
Interest rate 1.25%         5.25%  
Wall Street Journal Prime Rate | Revolving line of credit outstanding              
Debt Instrument [Line Items]              
Spread on variable rate     1.25%        
Interest rate     4.50%