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Retirement Plans - Defined Benefit Plan, Fair Value of Plan Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
United States [Member] | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets, beginning balance	$ 171,373	$ 144,665
Actual return on defined benefit plan assets	2,555	27,729
Company contributions	6,625	6,162
Plan settlements	(177,137)	(2,125)
Benefits paid	(3,416)	(5,058)
Fair value of defined benefit plan assets, ending balance		171,373
United States [Member] | Retiree Healthcare Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets, beginning balance	11,125	9,142
Actual return on defined benefit plan assets	(584)	1,542
Company contributions	387	347
Employee contributions	1,159	1,041
Benefits paid	(1,007)	(947)
Fair value of defined benefit plan assets, ending balance	11,080	11,125
Non-U.S. Pension Plans [Member] | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit plan assets, beginning balance	74,990	65,548
Actual return on defined benefit plan assets	1,070	390
Company contributions	10,778	4,733
Employee contributions	622	605
Plan settlements		(915)
Benefits paid	(3,277)	(2,078)
Other plans		(213)
Currency impact	(2,596)	6,920
Fair value of defined benefit plan assets, ending balance	$ 81,587	$ 74,990

X

- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

+ References

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contributions received by defined benefit plan from participant which increase benefit obligation.

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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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Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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Changes in the fair value of defined benefit plan assets, not otherwise separately disclosed in the financial statements.

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