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Related Party Transactions - Additional Information (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
May 02, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | $ 14,613,000 | $ 16,270,000
Investment income generated from mutual funds |  | $ 206,000 | $ (28,000)
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 |  | 0.35% |
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 |  | $ 493,000 | $ 203,000
Cash and Cash Equivalents [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | 8,992,000 | 12,506,000
Marketable Securities [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Balance with Fund Manager |  | $ 5,621,000 | $ 3,764,000

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- Definition Amount of transactions with related party during the financial reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864 + Details
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