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Retirement Plans - Defined Benefit Plan, Fair Value Measurement of Plan Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Significant Unobservable Inputs (Level 3) [Member] | Bank And Insurance Investment Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | $ 56,718 | $ 51,963 | $ 45,093
United States [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 11,080 | 11,125 | 9,142
United States [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets |  | 171,373 | 144,665
Non-U.S. Pension Plans [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 81,587 | 74,990 | $ 65,548
Retirement Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments valued at NAV |  | 7,935 |
Fair value of defined benefit plan assets |  | 257,488 |
Retirement Plans [Member] | Portion at Fair Value Measurement [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 92,667 | 249,553 |
Retirement Plans [Member] | Fair Value, Inputs, Level 1 [Member] | Portion at Fair Value Measurement [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 35,949 | 197,590 |
Retirement Plans [Member] | Significant Unobservable Inputs (Level 3) [Member] | Portion at Fair Value Measurement [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 56,718 | 51,963 |
Retirement Plans [Member] | United States [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 11,080 | 11,125 |
Retirement Plans [Member] | United States [Member] | Retiree Healthcare Plan [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 11,080 | 11,125 |
Retirement Plans [Member] | United States [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets |  | 163,438 |
Retirement Plans [Member] | United States [Member] | Pension Plans [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets |  | 163,438 |
Retirement Plans [Member] | United States [Member] | Fair Value, Inputs, Level 1 [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 11,080 | 11,125 |
Retirement Plans [Member] | United States [Member] | Fair Value, Inputs, Level 1 [Member] | Retiree Healthcare Plan [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 11,080 | 11,125 |
Retirement Plans [Member] | United States [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets |  | 163,438 |
Retirement Plans [Member] | United States [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Plans [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets |  | 163,438 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 81,587 | 74,990 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 20,430 | 17,244 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 4,439 | 5,783 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] | Bank And Insurance Investment Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 56,718 | 51,963 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 24,869 | 23,027 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Plans [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 20,430 | 17,244 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Fair Value, Inputs, Level 1 [Member] | Pension Plans [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 4,439 | 5,783 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Significant Unobservable Inputs (Level 3) [Member] | Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | 56,718 | 51,963 |
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Significant Unobservable Inputs (Level 3) [Member] | Pension Plans [Member] | Bank And Insurance Investment Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of defined benefit plan assets | $ 56,718 | $ 51,963 |

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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + 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 (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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- Definition Fair value of investment in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. + References No definition available. + Details
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