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Pension Plan (Tables)

12 Months Ended

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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Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate.

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Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.

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Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.

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