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v3.21.1

Related Party Transactions - Additional Information (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
May 02, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | $ 19,063,000 | $ 14,536,000
Investment income generated from mutual funds |  | $ 139,000 | $ 206,000
Minimum [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Percentage of stockholders controlling a related party |  | 10.00% | 10.00%
Maximum [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Fund management fee percent |  | 0.25% |
Aggregate loan amount to cover expense related to SPAC IPO pursuant to promissory note | $ 150,000 |  |
Other Income [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Investment income generated from mutual funds |  | $ 213,000 | $ 493,000
Cash and Cash Equivalents [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | 13,283,000 | 8,915,000
Marketable Securities [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | $ 5,780,000 | $ 5,621,000

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