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Pension Benefits - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2021 USD ($) | Dec. 31, 2021 TWD ($) | Dec. 31, 2021 HKD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Accumulated benefit obligation | $ 294,000 |  |  | $ 287,000 |
Prepaid pension | 83,000 |  |  | 67,000 |
Fair value of plan assets | 473,000 |  |  | 452,000 |
Accumulated other comprehensive loss | (80,000) |  |  | (94,000) |
Net periodic benefit cost | 3,000 |  |  | 1,000 | $ 2,000
Defined benefit plan, expected contribution in 2022 | 0 |  |  |  |
Expected future benefit payments from 2022 to 2026 | 1,000 |  |  |  |
Expected future benefit payments from 2027 to 2031 | $ 32,000 |  |  |  |
Hong Kong |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Percentage of salaries and wages contributed | 5.00% | 5.00% | 5.00% |  |
Pension Plan | Operating Expenses |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Total amount of defined contribution pension expenses | $ 193,000 |  |  | $ 187,000 | $ 187,000
Pension Plan | Taiwan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Percentage of salaries and wages contributed | 2.00% | 2.00% | 2.00% |  |
Maximum |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Lump sum retirement benefit, equivalent months of pensionable salary | 45 months | 45 months | 45 months |  |
Maximum | Taiwan | Monthly Payment |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Maximum monthly contribution for each employee | $ 325 | $ 9,000 |  |  |
Maximum | Hong Kong | Monthly Payment |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Maximum monthly contribution for each employee | $ 193 |  | $ 1,500 |  |
Minimum | Pension Plan | Taiwan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Percentage of salaries and wages contributed | 6.00% | 6.00% | 6.00% |  |
For each of first 15 years of service |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Lump sum retirement benefit, equivalent months of pensionable salary | 2 months | 2 months | 2 months |  |
For each year of service thereafter |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Lump sum retirement benefit, equivalent months of pensionable salary | 1 month | 1 month | 1 month |  |

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