Defined benefit plan assets (liabilities), net.

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- Definition

Defined benefit plan expected future benefit payments year one through five.

+ References

No definition available.

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- Definition

Defined benefit plan, expected future benefit payments, year six through ten.

+ References

No definition available.

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- Definition

Employee salary benefits payments period.

+ References

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

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- Definition

Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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Pension Benefits - Additional Information (Detail)	12 Months Ended
Pension Benefits - Additional Information (Detail)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 TWD ($)	Dec. 31, 2020 HKD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 287,000			$ 238,000
Prepaid pension	67,000			85,000
Fair value of plan assets	452,000			411,000
Accumulated other comprehensive loss	(94,000)			(66,000)
Net periodic benefit cost	1,000			2,000	$ 1,000
Defined benefit plan, expected contribution in 2021	0
Expected future benefit payments from 2021 to 2025	1,000
Expected future benefit payments from 2026 to 2030	$ 23,000
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	$ 187,000			$ 187,000	$ 210,000
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	$ 316	$ 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