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Schedule of Fair Value of Pensions Plan Assets by Asset Category (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Defined Benefit Plan Disclosure |  |  |
Total | $ 160,700 |  |
UNITED STATES |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 158,855 | $ 166,932 | $ 144,301
UNITED STATES | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,582 | 1,610 |
UNITED STATES | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 157,273 | 165,322 |
UNITED STATES | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Corporate Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 127,098 | 133,792 |
UNITED STATES | Corporate Debt Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Corporate Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 127,098 | 133,792 |
UNITED STATES | Corporate Debt Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | US Government Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 22,250 | 23,186 |
UNITED STATES | US Government Debt Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | US Government Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 22,250 | 23,186 |
UNITED STATES | US Government Debt Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Global equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 7,925 | 8,344 |
UNITED STATES | Global equity Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Global equity Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 7,925 | 8,344 |
UNITED STATES | Global equity Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Other |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Other | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Other | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Other | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,582 | 1,610 |
UNITED STATES | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,582 | 1,610 |
UNITED STATES | Cash and Cash Equivalents | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
UNITED STATES | Cash and Cash Equivalents | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,856 | 1,586 | $ 1,400
Foreign Pension Plans, Defined Benefit | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,856 | 1,586 |
Foreign Pension Plans, Defined Benefit | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Corporate Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Corporate Debt Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Corporate Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Corporate Debt Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | US Government Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | US Government Debt Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | US Government Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | US Government Debt Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Global equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Global equity Securities | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Global equity Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Global equity Securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Other |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,856 | 1,586 |
Foreign Pension Plans, Defined Benefit | Other | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Other | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,856 | $ 1,586 |
Foreign Pension Plans, Defined Benefit | Other | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 0 |  |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | $ 0 |  |

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