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Schedule of Fair Value of Pensions Plan Assets by Asset Category (Detail) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Defined Benefit Plan Disclosure |  |  |
Total | $ 145,700 |  |
Group Annuity Insurance Contracts | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total |  | $ 3,166 | $ 29,456
UNITED STATES |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 144,301 | 324,506 | 307,304
UNITED STATES | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,449 | 3,217 |
UNITED STATES | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 142,852 | 318,123 |
UNITED STATES | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total |  | 3,166 |
UNITED STATES | Corporate Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 115,424 | 260,294 |
UNITED STATES | Corporate Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 115,424 | 260,294 |
UNITED STATES | US Government Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 20,176 | 25,709 |
UNITED STATES | US Government Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 20,176 | 25,709 |
UNITED STATES | Global equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 7,252 | 32,120 |
UNITED STATES | Global equity Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 7,252 | 32,120 |
UNITED STATES | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,449 | 3,217 |
UNITED STATES | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,449 | 3,217 |
UNITED STATES | Group Annuity Insurance Contracts |  |  |
Defined Benefit Plan Disclosure |  |  |
Total |  | 3,166 |
UNITED STATES | Group Annuity Insurance Contracts | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total |  | 3,166 |
Foreign Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,400 | 1,307 | $ 27,571
Foreign Pension Plans, Defined Benefit | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,400 | 1,307 |
Foreign Pension Plans, Defined Benefit | Other |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,400 | 1,307 |
Foreign Pension Plans, Defined Benefit | Other | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | $ 1,400 | $ 1,307 |

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