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Schedule of Fair Value of Pensions Plan Assets by Asset Category (Detail) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Defined Benefit Plan Disclosure |  |  |
Total | $ 334,900 |  |
Group Annuity Insurance Contracts | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 29,456 | $ 29,392 | $ 2,990
United States Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 307,304 | 298,404 | 316,072
United States Pension Plans, Defined Benefit | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,023 | 1,773 |
United States Pension Plans, Defined Benefit | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 301,210 | 293,649 |
United States Pension Plans, Defined Benefit | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,071 | 2,982 |
United States Pension Plans, Defined Benefit | Corporate Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 246,528 | 240,695 |
United States Pension Plans, Defined Benefit | Corporate Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 246,528 | 240,695 |
United States Pension Plans, Defined Benefit | US Government Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 24,322 | 23,761 |
United States Pension Plans, Defined Benefit | US Government Debt Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 24,322 | 23,761 |
United States Pension Plans, Defined Benefit | Global equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 30,360 | 29,193 |
United States Pension Plans, Defined Benefit | Global equity Securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 30,360 | 29,193 |
United States Pension Plans, Defined Benefit | Group Annuity Insurance Contracts |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,071 | 2,982 |
United States Pension Plans, Defined Benefit | Group Annuity Insurance Contracts | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,071 | 2,982 |
United States Pension Plans, Defined Benefit | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,023 | 1,773 |
United States Pension Plans, Defined Benefit | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 3,023 | 1,773 |
Foreign Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 27,571 | 28,141 | $ 29,511
Foreign Pension Plans, Defined Benefit | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 62 | 702 |
Foreign Pension Plans, Defined Benefit | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,124 | 1,029 |
Foreign Pension Plans, Defined Benefit | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 26,385 | 26,410 |
Foreign Pension Plans, Defined Benefit | Group Annuity Insurance Contracts |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 26,385 | 26,410 |
Foreign Pension Plans, Defined Benefit | Group Annuity Insurance Contracts | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 26,385 | 26,410 |
Foreign Pension Plans, Defined Benefit | Other |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,124 | 1,029 |
Foreign Pension Plans, Defined Benefit | Other | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 1,124 | 1,029 |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | 62 | 702 |
Foreign Pension Plans, Defined Benefit | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1) |  |  |
Defined Benefit Plan Disclosure |  |  |
Total | $ 62 | $ 702 |

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