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Equity Investment in Unconsolidated Subsidiary - Additional Information (Details) - USD ($) |  |  | 12 Months Ended
--- | --- | --- | ---
Nov. 07, 2019 | Nov. 06, 2019 | Dec. 31, 2019
SPAC [Member] |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Amount raised through offering | $ 172,500,000 |  |
Shares sold in the offering | 17,250,000 |  |
LGL Systems Acquisition Holdings Company, LLC [Member] |  |  |
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% |
Percentage of sponsorship owned |  |  | 43.57%
Equity losses |  |  | $ 26,000
LGL Systems Acquisition Holdings Company, LLC [Member] | SPAC [Member] |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Warrant exercise/ strike price |  |  | $ 11.50
Percentage of sponsorship owned |  |  | 20.00%
Class of warrants held |  |  | 5,200,000
Number of restricted and non-tradeable shares held |  |  | 4,312,500
LGL Systems Acquisition Holdings Company, LLC [Member] | Private Placement [Member] |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Purchase of private warrants |  | $ 5,200,000 |
Warrant exercise/ strike price |  | $ 11.50 |
LGL Systems Acquisition Holdings Company, LLC [Member] | Common Stock [Member] | Private Placement [Member] |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Warrant exercisable to purchase common stock |  | 1 |

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