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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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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.

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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.

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