Schedule of Defined Benefit Plans Disclosures (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure
Transfer out of Level 3	$ 2,700
Ending Balance	145,700
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure
Settlements		$ (28,560)
Interest and market value adjustments	59	959
Benefits paid	(40)	(244)
Other	(15)	(61)
Significant Unobservable Inputs (Level 3) \| Group Annuity Insurance Contracts
Defined Benefit Plan Disclosure
Beginning Balance	3,166	29,456
Transfer out of Level 3	(2,658)
Purchases of retiree annuity insurance contracts	(512)
Non-U.S. currency movement		1,616
Ending Balance		$ 3,166

Defined benefit plan retiree annuity insurance contract purchase.

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- 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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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

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- Definition

Amount of increase (decrease) in benefit obligation of defined benefit plan from change, classified as other.

+ References

No definition available.

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. 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.

+ References

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- Definition

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

+ References

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan, for assets transferred into (out of) Level 3 of fair value hierarchy. Includes, but is not limited to, transfer due to change in observability of significant inputs.

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