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Pension and Severance Plans (Defined Benefit Plans - Allocation of plan assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 129,196	$ 127,338	$ 157,012
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	84,219	77,583
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	44,977	49,755
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	217	1,117
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	217	1,117
Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,680	13,339
Equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,680	13,339
Equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Government bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,674	2,982
Government bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,674	2,982
Government bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,130	540
Corporate bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,130	540
Corporate bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Treasury notes
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11,993	11,561
Treasury notes | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11,993	11,561
Treasury notes | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36,823	31,088
Equity funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	29,016	23,931
Equity funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,807	7,157
Debt funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25,194	25,060
Debt funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,031	11,651
Debt funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,163	13,409
Guaranteed investment contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23,189	28,340
Guaranteed investment contracts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Guaranteed investment contracts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23,189	28,340
Taiwan retirement fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,478	12,845
Taiwan retirement fund | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,478	12,845
Taiwan retirement fund | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	818	466
Other, net | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	(383)
Other, net | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 818	$ 849
Japan | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	64.00%
Japan | Other, net
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	2.00%
Japan | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	34.00%
Korea | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	30.00%
Korea | Other, net
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	50.00%
Korea | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	20.00%
Philippines | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	56.00%
Philippines | Other, net
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	2.00%
Philippines | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation (as a percent)	42.00%

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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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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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