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Equity Investment in Unconsolidated Subsidiary - Additional Information (Details) - LGL Systems Acquisition Holdings Company, LLC [Member] - USD ($) |  |  | 12 Months Ended
--- | --- | --- | ---
Nov. 12, 2019 | Nov. 06, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Contribution to fund purchase of private warrants |  | $ 3,350,000 |  |
Percentage of risk capital contributed to effect IPO |  | 62.20% |  |
Number of restricted and non-tradeable shares held |  | 5,200,000 |  |
Equity losses |  |  | $ 262,000 | $ 16,000
Cumulative loss on investments |  |  | $ 278,000 |
SPAC [Member] |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Percentage of sponsorship owned | 20.00% |  |  |
Class of warrants held | 5,200,000 |  |  |
SPAC [Member] | SPAC [Member] |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Amount raised through offering | $ 172,500,000 |  |  |
Private Placement [Member] |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Warrant exercise/ strike price |  | $ 11.50 |  |
Common Class B [Member] |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Percentage of sponsorship owned |  | 100.00% |  |
Common Stock [Member] | Private Placement [Member] |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Warrant exercisable to purchase common stock |  | 1 |  |

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