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Retirement Plans (Tables) | 12 Months Ended
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Dec. 31, 2019
Defined Benefit Pension Plans |
Defined Benefit Pension and Postretirement Benefit Plan Assets and Obligations | The December 31 balances of these defined benefit pension plans assets and obligations are shown below:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
|  | (in thousands) |
Assets and Obligations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in benefit obligation: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Projected benefit obligation: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of year |  | $ | 178,237 |  |  | $ | 39,146 |  |  | $ | 363,026 |  |  | $ | 39,353 |
Service cost |  |  | 1,608 |  |  |  | 751 |  |  |  | 2,196 |  |  |  | 786 |
Interest cost |  |  | 7,189 |  |  |  | 691 |  |  |  | 8,940 |  |  |  | 687 |
Actuarial loss (gain) |  |  | 24,447 |  |  |  | 4,520 |  |  |  | (30,136 | ) |  |  | 773 |
Benefits paid |  |  | (7,690 | ) |  |  | (836 | ) |  |  | (14,793 | ) |  |  | (741 | )
Retiree annuity purchase |  |  | — |  |  |  | — |  |  |  | (151,341 | ) |  |  | — |
Liability loss due to settlement |  |  | — |  |  |  | — |  |  |  | 345 |  |  |  | — |
Non-U.S. currency movement |  |  | — |  |  |  | (320 | ) |  |  | — |  |  |  | (1,712 | )
End of year |  |  | 203,791 |  |  |  | 43,952 |  |  |  | 178,237 |  |  |  | 39,146 |
Change in plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of year |  |  | 144,301 |  |  |  | 1,400 |  |  |  | 324,506 |  |  |  | 1,307 |
Company contributions |  |  | 2,805 |  |  |  | 923 |  |  |  | 2,587 |  |  |  | 822 |
Actual return on plan assets |  |  | 27,516 |  |  |  | 64 |  |  |  | (16,658 | ) |  |  | 50 |
Benefits paid |  |  | (7,690 | ) |  |  | (836 | ) |  |  | (14,793 | ) |  |  | (741 | )
Retiree annuity purchase |  |  | — |  |  |  | — |  |  |  | (151,341 | ) |  |  | — |
Non-U.S. currency movement |  |  | — |  |  |  | 35 |  |  |  | — |  |  |  | (38 | )
End of year |  |  | 166,932 |  |  |  | 1,586 |  |  |  | 144,301 |  |  |  | 1,400 |
Funded status |  | $ | (36,859 | ) |  | $ | (42,366 | ) |  | $ | (33,936 | ) |  | $ | (37,746 | )
Amounts Recorded within Statement of Financial Position | The following table provides amounts recorded within the account line items of the statements of financial position as of December 31:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
|  | (in thousands) |
Retirement plans assets |  | $ | 18,457 |  |  | $ | — |  |  | $ | 16,883 |  |  | $ | — |
Accrued employees’ compensation and withholdings |  |  | (2,826 | ) |  |  | (922 | ) |  |  | (2,676 | ) |  |  | (852 | )
Retirement plans liabilities |  |  | (52,490 | ) |  |  | (41,444 | ) |  |  | (48,143 | ) |  |  | (36,894 | )
Funded status |  | $ | (36,859 | ) |  | $ | (42,366 | ) |  | $ | (33,936 | ) |  | $ | (37,746 | )
Amounts Recognized in Accumulated Other Comprehensive Income | The following table provides amounts recognized in accumulated other comprehensive income as of December 31:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
|  | (in thousands) |
Deferred taxes related to prior service cost recognized in other comprehensive income |  | $ | 560 |  |  | $ | — |  |  | $ | 560 |  |  | $ | — |
Pension Plans with Accumulated Benefit Obligation and Projected Benefit Obligation in Excess of Plan Assets | Information for pension plans with an accumulated benefit obligation in excess of plan assets as of December 31:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
|  | (in millions) |
Projected benefit obligation |  | $ | 55.3 |  |  | $ | 44.0 |  |  | $ | 50.8 |  |  | $ | 39.1 |
Accumulated benefit obligation |  |  | 53.2 |  |  |  | 39.9 |  |  |  | 48.6 |  |  |  | 35.6 |
Fair value of plan assets |  |  | — |  |  |  | 1.6 |  |  |  | — |  |  |  | 1.4 |
Net Periodic Pension and Postretirement Benefit Costs | For the years ended December 31, 2019, 2018, and 2017, Teradyne’s net periodic pension cost (income) was comprised of the following:
|  | 2019 |  |  | 2018 |  |  | 2017 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
|  | (in thousands) |
Components of Net Periodic Pension Cost (Income): |  |  |  |  |  |  |  |  |
Service cost |  | $ | 1,608 |  |  | $ | 751 |  |  | $ | 2,196 |  |  | $ | 786 |  |  | $ | 2,239 |  |  | $ | 818 |
Interest cost |  |  | 7,189 |  |  |  | 691 |  |  |  | 8,940 |  |  |  | 687 |  |  |  | 13,151 |  |  |  | 852 |
Expected return on plan assets |  |  | (6,042 | ) |  |  | (29 | ) |  |  | (9,049 | ) |  |  | (19 | ) |  |  | (12,008 | ) |  |  | (165 | )
Amortization of prior service cost |  |  | — |  |  |  | — |  |  |  | 58 |  |  |  | — |  |  |  | 70 |  |  |  | — |
Net actuarial loss (gain) |  |  | 2,973 |  |  |  | 4,485 |  |  |  | (4,429 | ) |  |  | 743 |  |  |  | (6,712 | ) |  |  | (310 | )
Settlement loss |  |  | — |  |  |  | — |  |  |  | 345 |  |  |  | — |  |  |  | — |  |  |  | — |
Total net periodic pension cost (income) |  | $ | 5,728 |  |  | $ | 5,898 |  |  | $ | (1,939 | ) |  | $ | 2,197 |  |  | $ | (3,260 | ) |  | $ | 1,195 |
Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reversal of amortization items: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Prior service cost |  |  | — |  |  |  | — |  |  |  | (58 | ) |  |  | — |  |  |  | (70 | ) |  |  | — |
Total recognized in other comprehensive income |  |  | — |  |  |  | — |  |  |  | (58 | ) |  |  | — |  |  |  | (70 | ) |  |  | — |
Total recognized in net periodic pension cost (income) and other comprehensive income |  | $ | 5,728 |  |  | $ | 5,898 |  |  | $ | (1,997 | ) |  | $ | 2,197 |  |  | $ | (3,330 | ) |  | $ | 1,195 |
Weighted Average Assumptions to Determine Net Periodic Cost and Benefit Obligation | Weighted Average Assumptions to Determine Net Periodic Pension Cost at January 1:
|  | 2019 |  |  | 2018 |  |  | 2017 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
Discount rate |  |  | 4.1 | % |  |  | 1.8 | % |  |  | 3.4 | % |  |  | 1.8 | % |  |  | 3.9 | % |  |  | 1.8 | %
Expected return on plan assets |  |  | 4.3 |  |  |  | 2.0 |  |  |  | 4.3 |  |  |  | 1.5 |  |  |  | 4.0 |  |  |  | 2.0 |
Salary progression rate |  |  | 2.5 |  |  |  | 2.5 |  |  |  | 2.3 |  |  |  | 2.7 |  |  |  | 2.6 |  |  |  | 2.7 |
Weighted Average Assumptions to Determine Pension Obligations at December 31:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
Discount rate |  |  | 3.0 | % |  |  | 1.1 | % |  |  | 4.1 | % |  |  | 1.8 | %
Salary progression rate |  |  | 2.6 |  |  |  | 2.5 |  |  |  | 2.5 |  |  |  | 2.6 |
Weighted Average Pension Asset Allocations by Category | The following table provides weighted average pension asset allocation by asset category at December 31, 2019 and 2018:
|  | 2019 |  |  | 2018 |
|  | United States |  |  | Foreign |  |  | United States |  |  | Foreign |
Fixed income securities |  |  | 94.0 | % |  |  | — | % |  |  | 94.0 | % |  |  | — | %
Equity securities |  |  | 5.0 |  |  |  | — |  |  |  | 5.0 |  |  |  | — |
Other |  |  | 1.0 |  |  |  | 100.0 |  |  |  | 1.0 |  |  |  | 100.0 |
|  |  | 100.0 | % |  |  | 100.0 | % |  |  | 100.0 | % |  |  | 100.0 | %
Target Asset Allocation and Index for Each Asset Category | The target asset allocation and the index for each asset category for the U.S. Plan, per the investment policy, are as follows:
Asset Category: |  | Policy Index: |  | Target Allocation |
U.S. corporate fixed income |  | Barclays U.S. Corporate A or Better Index |  |  | 75 | %
Global equity |  | MSCI World Minimum Volatility Index |  |  | 5 |
U.S. government fixed income |  | Barclays U.S. Long Government Bond Index |  |  | 14 |
High yield fixed income |  | Barclays U.S. High Yield Index |  |  | 5 |
Cash |  | Citigroup Three Month U.S. Treasury Bill Index |  |  | 1 |
Changes in Fair Value of Pension Assets | The fair value of pension plan assets by asset category and by level at December 31, 2019 and December 31, 2018 were as follows:
|  | December 31, 2019 |
|  | United States |  |  | Foreign |
|  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
|  | (in thousands) |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt securities |  | $ | — |  |  | $ | 133,792 |  |  | $ | — |  |  | $ | 133,792 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
U.S. government securities |  |  | — |  |  |  | 23,186 |  |  |  | — |  |  |  | 23,186 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Global equity |  |  | — |  |  |  | 8,344 |  |  |  | — |  |  |  | 8,344 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Other |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 1,586 |  |  |  | — |  |  |  | 1,586 |
Cash and cash equivalents |  |  | 1,610 |  |  |  | — |  |  |  | — |  |  |  | 1,610 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total |  | $ | 1,610 |  |  | $ | 165,322 |  |  | $ | — |  |  | $ | 166,932 |  |  | $ | — |  |  | $ | 1,586 |  |  | $ | — |  |  | $ | 1,586 |
|  | December 31, 2018 |
|  | United States |  |  | Foreign |
|  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
|  | (in thousands) |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt securities |  | $ | — |  |  | $ | 115,424 |  |  | $ | — |  |  | $ | 115,424 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
U.S. government securities |  |  | — |  |  |  | 20,176 |  |  |  | — |  |  |  | 20,176 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Global equity |  |  | — |  |  |  | 7,252 |  |  |  | — |  |  |  | 7,252 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Other |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 1,400 |  |  |  | — |  |  |  | 1,400 |
Cash and cash equivalents |  |  | 1,449 |  |  |  | — |  |  |  | — |  |  |  | 1,449 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total |  | $ | 1,449 |  |  | $ | 142,852 |  |  | $ | — |  |  | $ | 144,301 |  |  | $ | — |  |  | $ | 1,400 |  |  | $ | — |  |  | $ | 1,400 |
Expected Future Benefit Payments | Future benefit payments are expected to be paid as follows:
|  | United States |  |  | Foreign |
|  | (in thousands) |
2020 |  | $ | 8,027 |  |  | $ | 1,237 |
2021 |  |  | 8,416 |  |  |  | 985 |
2022 |  |  | 9,163 |  |  |  | 982 |
2023 |  |  | 9,785 |  |  |  | 1,258 |
2024 |  |  | 10,558 |  |  |  | 1,098 |
2025-2029 |  |  | 59,665 |  |  |  | 6,129 |
Group Annuity Insurance Contracts |
Changes in Fair Value of Pension Assets | Changes in the fair value of Level 3 group annuity insurance contracts for the year ended December 31, 2018 were as follows:
|  | Group Annuity Insurance Contracts |
|  | (in thousands) |
Balance at December 31, 2017 |  | $ | 3,166 |
Transfer out of level 3 |  |  | (2,658 | )
Purchase s o f r etiree annuity insurance c ontracts |  |  | (512 | )
Interest and market value adjustments |  |  | 59 |
Benefits paid |  |  | (40 | )
Other |  |  | (15 | )
Balance at December 31, 2018 |  | $ | — |
Postretirement Benefit Plans |
Defined Benefit Pension and Postretirement Benefit Plan Assets and Obligations | The December 31 balances of the postretirement assets and obligations are shown below:
|  | 2019 |  |  | 2018 |
|  | (in thousands) |
Assets and Obligations |  |  |  |  |  |  |  |
Change in benefit obligation: |  |  |  |  |  |  |  |
Projected benefit obligation: |  |  |  |  |  |  |  |
Beginning of year |  | $ | 9,256 |  |  | $ | 6,177 |
Service cost |  |  | 41 |  |  |  | 39 |
Interest cost |  |  | 347 |  |  |  | 196 |
Actuarial loss |  |  | 717 |  |  |  | 25 |
Benefits paid |  |  | (1,358 | ) |  |  | (889 | )
Special termination benefits |  |  | — |  |  |  | 3,708 |
End of year |  |  | 9,003 |  |  |  | 9,256 |
Change in plan assets: |  |  |  |  |  |  |  |
Fair value of plan assets: |  |  |  |  |  |  |  |
Beginning of year |  |  | — |  |  |  | — |
Company contributions |  |  | 1,358 |  |  |  | 889 |
Benefits paid |  |  | (1,358 | ) |  |  | (889 | )
End of year |  |  | — |  |  |  | — |
Funded status |  | $ | (9,003 | ) |  | $ | (9,256 | )
Amounts Recorded within Statement of Financial Position | The following table provides amounts recorded within the account line items of financial position as of December 31:
|  | 2019 |  |  | 2018 |
|  | (in thousands) |
Accrued employees’ compensation and withholdings |  | $ | (1,231 | ) |  | $ | (1,310 | )
Retirement plans liability |  |  | (7,772 | ) |  |  | (7,946 | )
Funded status |  | $ | (9,003 | ) |  | $ | (9,256 | )
Amounts Recognized in Accumulated Other Comprehensive Income | The following table provides amounts recognized in accumulated other comprehensive income as of December 31:
|  | 2019 |  |  | 2018 |
|  | (in thousands) |
Prior service credit, before tax |  | $ | (58 | ) |  | $ | (249 | )
Deferred taxes |  |  | (1,684 | ) |  |  | (1,641 | )
Total recognized in other comprehensive income, net of tax |  | $ | (1,742 | ) |  | $ | (1,890 | )
Net Periodic Pension and Postretirement Benefit Costs | For the years ended December 31, 2019, 2018, and 2017, Teradyne’s net periodic postretirement benefit cost (income) was comprised of the following:
|  | 2019 |  |  | 2018 |  |  | 2017 |
|  | (in thousands) |
Components of Net Periodic Postretirement Benefit Cost (income): |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 41 |  |  | $ | 39 |  |  | $ | 34 |
Interest cost |  |  | 347 |  |  |  | 196 |  |  |  | 201 |
Amortization of prior service credit |  |  | (191 | ) |  |  | (373 | ) |  |  | (496 | )
Net actuarial loss |  |  | 717 |  |  |  | 25 |  |  |  | 398 |
Special termination benefits |  |  | — |  |  |  | 3,708 |  |  |  | 591 |
Total net periodic postretirement benefit cost |  |  | 914 |  |  |  | 3,595 |  |  |  | 728 |
Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |
Prior service cost |  |  | — |  |  |  | — |  |  |  | — |
Reversal of amortization items: |  |  |  |  |  |  |  |  |  |  |  |
Prior service credit |  |  | 191 |  |  |  | 373 |  |  |  | 496 |
Total recognized in other comprehensive income |  |  | 191 |  |  |  | 373 |  |  |  | 496 |
Total recognized in net periodic postretirement cost and other comprehensive income |  | $ | 1,105 |  |  | $ | 3,968 |  |  | $ | 1,224 |
Weighted Average Assumptions to Determine Net Periodic Cost and Benefit Obligation | Weighted Average Assumptions to Determine Net Periodic Postretirement Benefit Income as of January 1:
|  | 2019 |  |  | 2018 |  |  | 2017 |
Discount rate |  |  | 4.0 | % |  |  | 3.4 | % |  |  | 3.9 | %
Initial health care cost trend rate |  |  | 7.5 |  |  |  | 7.9 |  |  |  | 7.3 |
Ultimate health care cost trend rate |  |  | 4.5 |  |  |  | 4.5 |  |  |  | 5.0 |
Year in which ultimate health care cost trend rate is reached |  |  | 2026 |  |  |  | 2026 |  |  |  | 2023 |
Weighted Average Assumptions to Determine Postretirement Benefit Obligation as of December 31:
|  | 2019 |  |  | 2018 |  |  | 2017 |
Discount rate |  |  | 3.0 | % |  |  | 4.0 | % |  |  | 3.4 | %
Initial medical trend |  |  | 7.1 |  |  |  | 7.5 |  |  |  | 7.9 |
Ultimate health care trend |  |  | 4.5 |  |  |  | 4.5 |  |  |  | 4.5 |
Medical cost trend rate decrease to ultimate rate in year |  |  | 2026 |  |  |  | 2026 |  |  |  | 2026 |
Expected Future Benefit Payments | Future benefit payments are expected to be paid as follows:
|  | Benefit Payments |
|  | (in thousands) |
2020 |  | $ | 1,231 |
2021 |  |  | 1,171 |
2022 |  |  | 958 |
2023 |  |  | 789 |
2024 |  |  | 662 |
2025-2029 |  |  | 1,965 |
One Percentage Point Change in Assumed Health Care Cost Trend Rates for Year | A one percentage point change in the assumed health care cost trend rates for the year ended December 31, 2019 would have the following effects:
|  | 1 Percentage Point Increase |  |  | 1 Percentage Point Decrease |
|  | (in thousands) |
Effect on total service and interest cost components |  | $ | 6 |  |  | $ | (6 | )
Effect on postretirement benefit obligations |  |  | 139 |  |  |  | (133 | )

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