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Pension and Severance Plans (Tables) | 12 Months Ended
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Dec. 31, 2024
Retirement Benefits [Abstract] |
Schedule of Accrued Severance Obligation | The changes to the balance of our accrued severance plan obligations are as follows:
| For the Year Ended December 31,
| 2024 |  | 2023 |  |
| (In thousands)
Balance at January 1 | $ | 47,906 |  |  | $ | 56,289 |  |  |
Provision of severance benefits | 3,142 |  |  | 1,653 |  |  |
Severance payments | (1,416) |  |  | (8,770) |  |  |
Foreign currency (gain) loss | (6,194) |  |  | (1,266) |  |  |
Balance at December 31 | 43,438 |  |  | 47,906 |  |  |
Payments remaining with the National Pension Fund | (101) |  |  | (119) |  |  |
Total accrued severance plan obligations at December 31 | 43,337 |  |  | 47,787 |  |  |
Less current portion of accrued severance plan obligations (Note 10) (1) | 12,231 |  |  | 7,906 |  |  |
Non-current portion of accrued severance plan obligations | $ | 31,106 |  |  | $ | 39,881 |  |  |
(1)In December 2024, some employees accepted our offer to convert their Korean severance and defined benefit pension plan participation to a defined contribution plan. This will result in the conversion of approximately $5 million of obligations from our Korean severance plan to a defined contribution plan, which is expected to be funded during the first quarter of 2025.
Schedule of Changes in Projected Benefit Obligations and Fair Value of Plan Assets | The following table summarizes the changes to the Plans’ benefit obligations, fair value of the Plans’ assets and the funded status of the Plans at December 31, 2024 and 2023:
| For the Year Ended December 31,
| 2024 |  | 2023
| (In thousands)
Change in projected benefit obligation: |  |  |
Projected benefit obligation at January 1 | $ | 164,281 |  |  | $ | 159,760 |
Service cost | 13,645 |  |  | 15,032 |
Interest cost | 5,718 |  |  | 6,202 |
Benefits paid | (11,320) |  |  | (14,056) |
Actuarial (gain) loss | 2,458 |  |  | 4,150 |
Effects of curtailment | (320) |  |  | (617) |
Settlement | (883) |  |  | (1,073) |
Foreign exchange (gain) loss | (14,423) |  |  | (5,117) |
Projected benefit obligation at December 31 | 159,156 |  |  | 164,281 |
Change in plan assets: |  |  |
Fair value of plan assets at January 1 | 129,196 |  |  | 127,338 |
Actual gain (loss) on plan assets | 8,918 |  |  | 12,325 |
Employer contributions | 12,165 |  |  | 7,368 |
Settlement | (883) |  |  | (1,073) |
Benefits paid | (11,320) |  |  | (14,056) |
Foreign exchange gain (loss) | (12,794) |  |  | (2,706) |
Fair value of plan assets at December 31 | 125,282 |  |  | 129,196 |
Funded status of the Plans at December 31 | $ | (33,874) |  |  | $ | (35,085) |
Schedule of Defined Benefit Plans - Balance Sheet |
| December 31,
| 2024 |  | 2023
| (In thousands)
Amounts recognized in the Consolidated Balance Sheets consist of: |  |  |
Prepaid benefit cost (included in non-current assets) | $ | 5,991 |  |  | $ | 12,039 |
Accrued benefit liability (included in pension and severance obligations) (1) | (39,865) |  |  | (47,124) |
Net amount recognized at year end | $ | (33,874) |  |  | $ | (35,085) |
(1)As of December 31, 2024, $0.9 million was recognized in accrued expenses.
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) | The following table summarizes, by component, the change in accumulated other comprehensive income (loss), net of tax related to our Plans:
| Prior Service Cost |  | Actuarial Net Gain (Loss) |  | Total
| (In thousands)
Balance at December 31, 2022 | $ | 602 |  |  | $ | 13,618 |  |  | $ | 14,220 |
Amortization and settlement gain included in net periodic pension cost | — |  |  | (46) |  |  | (46) |
Net gain (loss) arising during period | — |  |  | 1,731 |  |  | 1,731 |
Adjustments to unrealized components of defined benefit pension plan included in other comprehensive income (loss) | — |  |  | 1,685 |  |  | 1,685 |
Balance at December 31, 2023 | $ | 602 |  |  | $ | 15,303 |  |  | $ | 15,905 |
Amortization and settlement gain included in net periodic pension cost | — |  |  | (388) |  |  | (388) |
Net gain (loss) arising during period | — |  |  | 1,053 |  |  | 1,053 |
Adjustments to unrealized components of defined benefit pension plan included in other comprehensive income (loss) | — |  |  | 665 |  |  | 665 |
Balance at December 31, 2024 | $ | 602 |  |  | $ | 15,968 |  |  | $ | 16,570 |
Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets | Information for pension plans with benefit obligations in excess of plan assets is as follows:
| December 31,
| 2024 |  | 2023
| (In thousands)
Plans with underfunded or non-funded projected benefit obligation: |  |  |
Aggregate projected benefit obligation | $ | 92,191 |  |  | $ | 100,662 |
Aggregate fair value of plan assets | 52,326 |  |  | 53,539 |
Plans with underfunded or non-funded accumulated benefit obligation: |  |  |
Aggregate accumulated benefit obligation | 55,646 |  |  | 60,638 |
Aggregate fair value of plan assets | 20,122 |  |  | 21,304 |
Schedule of Components of Net Periodic Pension Cost | The following table summarizes total pension expense:
| For the Year Ended December 31,
| 2024 |  | 2023 |  | 2022
| (In thousands)
Components of net periodic pension cost and total pension expense: |  |  |  |  |
Service cost | $ | 13,645 |  |  | $ | 15,032 |  |  | $ | 20,072 |
Interest cost | 5,718 |  |  | 6,202 |  |  | 4,731 |
Expected return on plan assets | (5,554) |  |  | (5,144) |  |  | (5,605) |
Recognized actuarial (gain) loss | (462) |  |  | (156) |  |  | 53 |
Net periodic pension cost | 13,347 |  |  | 15,934 |  |  | 19,251 |
Curtailment (gain) loss | (320) |  |  | (617) |  |  | — |
Settlement (gain) loss | 33 |  |  | 132 |  |  | (1,374) |
Total pension expense | $ | 13,060 |  |  | $ | 15,449 |  |  | $ | 17,877 |
Schedule of Weighted-average Assumptions Used in Computing the Net Periodic Pension Cost and Projected Benefit Obligations | The following table summarizes the weighted-average assumptions used in computing the net periodic pension cost and projected benefit obligations:
| For the Year Ended December 31,
| 2024 |  | 2023 |  | 2022
Discount rate for determining net periodic pension cost | 3.8 | % |  | 4.2 | % |  | 2.6 | %
Discount rate for determining benefit obligations at December 31 | 3.8 | % |  | 3.8 | % |  | 4.2 | %
Rate of compensation increase for determining net periodic pension cost | 3.7 | % |  | 3.6 | % |  | 3.7 | %
Rate of compensation increase for determining benefit obligations at December 31 | 3.8 | % |  | 3.7 | % |  | 3.6 | %
Expected rate of return on plan assets for determining net periodic pension cost | 4.5 | % |  | 4.1 | % |  | 3.8 | %
Schedule of Allocation of Plan Assets | The current rate of return assumption targets are based on asset allocation strategies as follows:
| Allocation
| Debt |  | Equity |  | Other
Japan defined benefit plan | 64 | % |  | 34 | % |  | 2 | %
Korea defined benefit plan | 30 | % |  | 20 | % |  | 50 | %
Philippine defined benefit plan | 50 | % |  | 45 | % |  | 5 | %
The fair value of our pension plan assets, by asset category utilizing the fair value hierarchy as discussed in Note 16, is as follows:
| December 31, 2024 |  | December 31, 2023 |  |  |  |  |
| Level 1 |  | Level 2 |  |  |  | Total |  | Level 1 |  | Level 2 |  |  | Total |  |  |  |  |
| (In thousands) |  | (In thousands) |  |  |  |  |
Cash and cash equivalents | $ | 749 |  |  | $ | — |  |  |  |  | $ | 749 |  |  | $ | 217 |  |  | $ | — |  |  |  | $ | 217 |  |  |  |  |  |
Equity securities | 14,276 |  |  | — |  |  |  |  | 14,276 |  |  | 13,680 |  |  | — |  |  |  | 13,680 |  |  |  |  |  |
Debt securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Government bonds | 3,712 |  |  | — |  |  |  |  | 3,712 |  |  | 3,674 |  |  | — |  |  |  | 3,674 |  |  |  |  |  |
Corporate bonds | 1,259 |  |  | — |  |  |  |  | 1,259 |  |  | 1,130 |  |  | — |  |  |  | 1,130 |  |  |  |  |  |
Treasury notes | 11,881 |  |  | — |  |  |  |  | 11,881 |  |  | 11,993 |  |  | — |  |  |  | 11,993 |  |  |  |  |  |
Mutual and commingled funds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity funds | 11,950 |  |  | 7,270 |  |  |  |  | 19,220 |  |  | 29,016 |  |  | 7,807 |  |  |  | 36,823 |  |  |  |  |  |
Debt funds | 18,210 |  |  | 12,516 |  |  |  |  | 30,726 |  |  | 12,031 |  |  | 13,163 |  |  |  | 25,194 |  |  |  |  |  |
Guaranteed investment contracts | — |  |  | 30,365 |  |  |  |  | 30,365 |  |  | — |  |  | 23,189 |  |  |  | 23,189 |  |  |  |  |  |
Taiwan retirement fund | 12,428 |  |  | — |  |  |  |  | 12,428 |  |  | 12,478 |  |  | — |  |  |  | 12,478 |  |  |  |  |  |
Other, net | — |  |  | 666 |  |  |  |  | 666 |  |  | — |  |  | 818 |  |  |  | 818 |  |  |  |  |  |
Total fair value of pension plan assets | $ | 74,465 |  |  | $ | 50,817 |  |  |  |  | $ | 125,282 |  |  | $ | 84,219 |  |  | $ | 44,977 |  |  |  | $ | 129,196 |  |  |  |  |  |
Schedule of Expected Benefit Payments | The estimated future benefit payments related to our foreign defined benefit plans are as follows:
| Payments
| (In thousands)
2025 | $ | 9,307 |
2026 | 11,145 |
2027 | 13,419 |
2028 | 14,037 |
2029 | 13,922 |
2030 to 2034 | 97,256 |

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