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Retirement Plans - Defined Benefit Plan, Fair Value Measurement of Plan Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Significant Unobservable Inputs (Level 3) | Bank and Insurance Investment Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	$ 60,119	$ 56,718	$ 51,963
UNITED STATES | Retiree Healthcare Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	13,773	11,080	11,125
UNITED STATES | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets			171,373
Non-U.S. Pension Plans [Member] | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	83,011	81,587	$ 74,990
Retirement Plans [Member] | Portion at Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	96,784	92,667
Retirement Plans [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Portion at Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	36,665	35,949
Retirement Plans [Member] | Significant Unobservable Inputs (Level 3) | Portion at Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	60,119	56,718
Retirement Plans [Member] | UNITED STATES | Retiree Healthcare Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	13,773	11,080
Retirement Plans [Member] | UNITED STATES | Retiree Healthcare Plan [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	13,773	11,080
Retirement Plans [Member] | UNITED STATES | Quoted Prices in Active Market for Identical Assets (Level 1) | Retiree Healthcare Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	13,773	11,080
Retirement Plans [Member] | UNITED STATES | Quoted Prices in Active Market for Identical Assets (Level 1) | Retiree Healthcare Plan [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	13,773	11,080
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	83,011	81,587
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	22,202	20,430
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Pension Plans [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	690	4,439
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	60,119	56,718
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	22,892	24,869
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Pension Plans [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	22,202	20,430
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Pension Plans [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	690	4,439
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Significant Unobservable Inputs (Level 3) | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	60,119	56,718
Retirement Plans [Member] | Non-U.S. Pension Plans [Member] | Significant Unobservable Inputs (Level 3) | Pension Plans [Member] | Bank and Insurance Investment Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets	$ 60,119	$ 56,718

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+ References

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