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Marketable Securities - Additional Information (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) | Sep. 14, 2021 shares
Marketable Securities [Line Items] |  |  |  |  |
Unrealized (loss) gain on marketable securities | $ | $ (18,867,000) | $ 122,000 | $ (18,665,000) | $ 15,000 |
IronNet [Member] | Private Warrants [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor | 2,065,000 |  | 2,065,000 |  |
Warrant exercisable to purchase common stock | 1 |  | 1 |  |
Warrant exercise/ strike price | $ / shares | $ 11.50 |  | $ 11.50 |  |
Warrant contractual term |  |  | 5 years |  |
Free-traded of common shares | 1,271,406 |  | 1,271,406 |  |
IronNet [Member] | Expected Dividend Rate [Member] | Private Warrants [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Measurement input, dividend rate on warrants | 0 |  | 0 |  |
IronNet [Member] | Private Warrants [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor | 2,065,000 |  | 2,065,000 |  |
IronNet [Member] | Private Warrants [Member] | LGL Systems Acquisition Holdings Company, LLC [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor |  |  |  |  | 2,065,000
IronNet [Member] | Common Stock [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor | 1,250,000 |  | 1,250,000 |  |
Distribution of shares by sponsor subject to certain founder share restrictions | 1,300,000 |  | 1,300,000 |  |
Distribution of shares by sponsor after charitable contribution | 50,000 |  | 50,000 |  |
IronNet [Member] | Common Stock [Member] | LGL Systems Acquisition Holdings Company, LLC [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor |  |  |  |  | 1,572,529
IronNet [Member] | PIPE Related Common Shares [Member] |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Distribution of shares by sponsor | 272,529 |  | 272,529 |  |

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