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Retirement Plans - Defined Benefit Plan, Fair Value of Plan Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
United States [Member] | Pension Plans [Member]
Fair value of defined benefit plan assets, beginning balance		$ 171,373
Actual return on plan assets		2,555
Company contributions	$ 969	6,625
Plan settlements	(969)	(177,137)
Benefits paid	0	(3,416)
United States [Member] | Retiree Healthcare Plan [Member]
Fair value of defined benefit plan assets, beginning balance	11,080	11,125
Actual return on plan assets	2,140	(584)
Company contributions	448	387
Employee contributions	1,214	1,159
Benefits paid	(1,109)	(1,007)
Fair value of defined benefit plan assets, ending balance	13,773	11,080
Non-U.S. Pension Plans [Member] | Pension Plans [Member]
Fair value of defined benefit plan assets, beginning balance	81,587	74,990
Actual return on plan assets	6,237	1,070
Company contributions	6,103	10,778
Employee contributions	499	622
Plan settlements	(7,044)
Benefits paid	(3,281)	(3,277)
Other plans	82
Currency impact	(1,172)	(2,596)
Fair value of defined benefit plan assets, ending balance	$ 83,011	$ 81,587

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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