Warrants - fair value of warrants (Details) - USD ($) |
2 Months Ended | 3 Months Ended | 11 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|---|
Mar. 31, 2020 |
Mar. 31, 2021 |
Mar. 31, 2020 |
Dec. 31, 2020 |
Dec. 31, 2020 |
Dec. 31, 2019 |
|
| Class of Warrant or Right [Line Items] | ||||||
| Changes in the fair value of warrants | $ 0 | $ 2,646,000 | $ 10,571,000 | |||
| Evolv Technologies Holdings Inc [Member] | ||||||
| Class of Warrant or Right [Line Items] | ||||||
| Changes in the fair value of warrants | $ 736,000 | $ 0 | ||||
| Evolv Technologies Holdings Inc [Member] | Maximum | ||||||
| Class of Warrant or Right [Line Items] | ||||||
| Changes in the fair value of warrants | $ 100,000 | $ 100,000 | ||||
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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- Details
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