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Pension Plan (Tables) | 12 Months Ended
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Dec. 31, 2020
Retirement Benefits [Abstract] |
Changes in Benefits Obligation and Plan Assets and Reconciliation of Funded Status | The changes in benefits obligation and plan assets and the reconciliation of funded status are as follows:
|  | December 31 |
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | US$ |  |  | US$ |  |  | US$ |
Change in benefit obligation |  |  |  |  |  |  |  |  |  |  |  |
Projected benefit obligation at beginning of year |  |  | 5,131 |  |  |  | 5,838 |  |  |  | 1,754 |
Service cost |  |  | 568 |  |  |  | 275 |  |  |  | 5 |
Interest cost |  |  | 126 |  |  |  | 91 |  |  |  | 5 |
Actuarial loss (gain) |  |  | 146 |  |  |  | 72 |  |  |  | (8 | )
Benefits paid |  |  | (133 | ) |  |  | (450 | ) |  |  | (40 | )
Disposal of subsidiary |  |  | — |  |  |  | (4,072 | ) |  |  | — |
Projected benefit obligation at end of year |  |  | 5,838 |  |  |  | 1,754 |  |  |  | 1,716 |
Change in plan assets |  |  |  |  |  |  |  |  |  |  |  |
Fair value of plan assets at beginning of year |  |  | 5,114 |  |  |  | 5,410 |  |  |  | 1,487 |
Actual return on plan assets |  |  | 63 |  |  |  | 98 |  |  |  | 49 |
Employer contributions |  |  | 331 |  |  |  | 85 |  |  |  | 49 |
Benefits paid |  |  | (98 | ) |  |  | (448 | ) |  |  | (34 | )
Disposal of subsidiary |  |  | — |  |  |  | (3,658 | ) |  |  | — |
Fair value of plan assets at end of year |  |  | 5,410 |  |  |  | 1,487 |  |  |  | 1,551 |
Funded status recognized as an other liabilities |  |  | (428 | ) |  |  | (267 | ) |  |  | (165 | )
Amounts Recognized in Accumulated Other Comprehensive Income | Amounts recognized in accumulated other comprehensive income consist of the following:
|  | Year Ended December 31 |
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | US$ |  |  | US$ |  |  | US$ |
Net loss |  |  | 678 |  |  |  | 693 |  |  |  | 754 |
Total recognized in accumulated other comprehensive income |  |  | 678 |  |  |  | 693 |  |  |  | 754 |
Components of Net Periodic Benefit Cost | The components of net periodic benefit cost are as follows:
|  | Year Ended December 31 |
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | US$ |  |  | US$ |  |  | US$ |
Service cost |  |  | 568 |  |  |  | 275 |  |  |  | 5 |
Interest cost |  |  | 126 |  |  |  | 91 |  |  |  | 5 |
Projected return on plan assets |  |  | (78 | ) |  |  | (77 | ) |  |  | (29 | )
Amortization of unrecognized net transition obligation and unrecognized net actuarial gain |  |  | 41 |  |  |  | 48 |  |  |  | 37 |
Net periodic benefit cost |  |  | 657 |  |  |  | 337 |  |  |  | 18 |
Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Loss | Other changes in plan assets and benefit obligation recognized in other comprehensive loss:
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | US$ |  |  | US$ |  |  | US$ |
Recognize the decrease in net gain (loss) |  |  | — |  |  |  | 15 |  |  |  | 61 |
Total recognized in other comprehensive loss (income) |  |  | — |  |  |  | 15 |  |  |  | 61 |
Expected Benefit Payments | Expected benefit payments:
|  | US$ |
2021 |  |  | 7 |
2022 |  |  | 21 |
2023 |  |  | 16 |
2024 |  |  | 82 |
2025 |  |  | 50 |
2026 and thereafter |  |  | 308 |
Actuarial Assumptions to Determine Benefit Obligations | The actuarial assumptions to determine the benefit obligations were as follows:
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | Taiwan |  |  | Korea |  |  | Taiwan |  |  | Taiwan |
Weighted-average assumptions used to determine benefit obligations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 1.38 | % |  |  | 3.60 | % |  |  | 1.00 | % |  |  | 0.50 | %
Rate of compensation increase |  |  | 4.25 | % |  |  | 3.00 | % |  |  | 4.00 | % |  |  | 4.00 | %
Weighted-average assumptions used to determine net projected benefit cost: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 1.38 | % |  |  | 3.60 | % |  |  | 1.00 | % |  |  | 0.50 | %
Expected long-term return on plan assets |  |  | 1.75 | % |  |  | 1.40 | % |  |  | 2.00 | % |  |  | 2.00 | %
Rate of compensation increase |  |  | 4.25 | % |  |  | 3.00 | % |  |  | 4.00 | % |  |  | 4.00 | %

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