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Employee Benefits - Sensitivity of Disclosures to Changes in Selected Assumptions (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
25 BP Decrease in Discount Rate, Change in ABO	$ 2,180
25 BP Decrease in Discount Rate, Change in pension expense	265
U.S Plans [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
25 BP Decrease in Discount Rate, Change in PBO	18,716
25 BP Decrease in Discount Rate, Change in ABO	18,657
25 BP Decrease in Discount Rate, Change in pension expense	(219)
25 BP Decrease in Long-Term Rate of Return, Change in pension expense	1,266
Non-U.S. Plans [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
25 BP Decrease in Discount Rate, Change in PBO	69,107
25 BP Decrease in Discount Rate, Change in ABO	66,092
25 BP Decrease in Discount Rate, Change in pension expense	3,705
25 BP Decrease in Long-Term Rate of Return, Change in pension expense	$ 2,663

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- Definition

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+ References

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- Definition

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- Definition

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- Definition

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- Definition

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