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Retirement Plans - Additional Information (Detail) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 USD ($) | Sep. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2020 USD ($) Participant | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Number of retiree participants | Participant |  |  |  |  | 115 |  |
Defined Benefit Plan, decrease in benefit obligation |  |  |  |  | $ 4,000 |  |
Defined Benefit Plan, decrease in plan assets |  |  |  |  | 24,400 |  |
Actrual loss on benefit obligations | $ (7,700) | $ (2,700) | $ (100) | $ (7,700) |  | $ 29,000 |
Gain (Loss) Due to Settlement |  |  |  |  | (500) |  |
Fair value of pension plans assets totaled | 160,700 |  |  |  | 160,700 |  |
UNITED STATES |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Actrual loss on benefit obligations |  |  |  |  | (24,671) | (24,447) |
Accumulated benefit obligation for defined benefit pension plans | $ 196,700 |  |  | $ 198,200 | $ 196,700 | $ 198,200 |
Percentage of expected return on plan assets assumption |  |  |  |  | 3.00% | 4.30% | 4.30%
Discount rate utilized to determine future pension obligations | 2.20% |  |  | 3.00% | 2.20% | 3.00% |
Fair value of pension plans assets totaled | $ 158,855 |  |  | $ 166,932 | $ 158,855 | $ 166,932 | $ 144,301
Contribution to defined benefit pension plans |  |  |  |  | 3,098 | 2,805 |
Foreign Pension Plans, Defined Benefit |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Actrual loss on benefit obligations |  |  |  |  | (2,951) | (4,520) |
Accumulated benefit obligation for defined benefit pension plans | $ 46,500 |  |  | $ 39,900 | $ 46,500 | $ 39,900 |
Percentage of expected return on plan assets assumption |  |  |  |  | 3.80% | 2.00% | 1.50%
Discount rate utilized to determine future pension obligations | 0.70% |  |  | 1.10% | 0.70% | 1.10% |
Fair value of pension plans assets totaled | $ 1,856 |  |  | $ 1,586 | $ 1,856 | $ 1,586 | $ 1,400
Contribution to defined benefit pension plans |  |  |  |  | 1,079 | 923 |
Postretirement Benefit Plans |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Defined Benefit Plan, decrease in benefit obligation |  |  |  |  | 27,600 |  |
Actrual loss on benefit obligations |  |  |  |  | $ (421) | $ (717) |
Discount rate utilized to determine future pension obligations | 2.20% |  |  | 3.00% | 2.20% | 3.00% | 4.00%
Fair value of pension plans assets totaled | $ 0 |  |  | $ 0 | $ 0 | $ 0 |
Contribution to defined benefit pension plans |  |  |  |  | $ 1,205 | $ 1,358 |
United States Plans |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Percentage of expected return on plan assets assumption |  |  |  |  | 3.00% |  |
Discount rate utilized to determine future pension obligations | 2.30% |  |  | 3.10% | 2.30% | 3.10% |
Fair value of pension plans assets totaled | $ 158,900 |  |  |  | $ 158,900 |  |
U.S. Supplemental Executive Defined Benefit Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Contribution to defined benefit pension plans |  |  |  |  | 3,100 | $ 2,800 |
Contribution to defined benefit pension plans in 2018 | 3,300 |  |  |  | 3,300 |  |
Non-United States Subsidiaries |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Contribution to defined benefit pension plans |  |  |  |  | 1,100 | $ 900 |
Contribution to defined benefit pension plans in 2018 | 1,100 |  |  |  | 1,100 |  |
Taiwan Defined Benefit Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Fair value of pension plans assets totaled | $ 1,900 |  |  |  | $ 1,900 |  |

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- Definition Defined Benefit Plan Number of Retiree Participants Who Had Deferred Vested Benefits Transferred to Insurance + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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