XML 220 R211.htm IDEA: XBRL DOCUMENT v3.21.2
Fair Value Measurements - Derivative liability (Details) - Evolv Technologies Holdings Inc [Member] - Derivative Liability
$ in Thousands
3 Months Ended
Mar. 31, 2021
USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance at beginning $ 1,000
Initial fair value of the embedded derivative 7,006
Change in fair value 1,425
Balance at ending $ 9,431