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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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