Employee Benefits - Reconciliation of Level 3 Non-U.S. Plan Assets Held (Detail) - Pension Plan [Member] - Non-U.S. Plans [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 1,005,283	$ 896,782
Actual return on plan assets	83,625	100,163
Fair value of plan assets at end of year	1,144,962	1,005,283
Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,005,283
Fair value of plan assets at end of year	1,144,962	1,005,283
Level 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	114,195
Actual return on plan assets	10,335
Purchases, sales and settlements	(11,133)
Fair value of plan assets at end of year	113,397	114,195
Level 3 [Member] \| Real Estate [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	84,013
Actual return on plan assets	8,677
Purchases, sales and settlements	1,871
Fair value of plan assets at end of year	94,561	84,013
Level 3 [Member] \| Hedge Funds [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	30,182
Actual return on plan assets	1,658
Purchases, sales and settlements	(13,004)
Fair value of plan assets at end of year	$ 18,836	$ 30,182

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.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

+ References

+ Details

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