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Investments - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Schedule of Investments [Line Items] |  |  |
Purchase an available-for-sale debt with credit deterioration | $ 0 | $ 0 | $ 0
Asset impairments | 0 | 65,000 | 3,872,000
Unsecured loan converted to equity investment | 500,000 |  |
Carrying value of equity investment | 1,000,000.0 | 800,000 |
Unsecured loan |  | 500,000 |
Secured note receivable, noncurrent | 400,000 | 900,000 |
Secured Loans Receivable [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Asset impairments | 500,000 | 0 | 0
Net Investment Gain (Loss) [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Asset impairments | 400,000 | 2,600,000 | $ 0
Long-term Investments [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Secured note receivable, noncurrent | $ 400,000 | $ 900,000 |
Investment [Member] | Issuer Concentration [Member] | Market Value of Total Investment Portfolio [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Concentration risk, percentage | 5.00% |  |

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