Portion of Deferred Compensation Plan to be paid out in shares.

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Defined contribution plan, matching participant contribution, percentage on compensation, range high

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Defined contribution plan, matching participant contribution, percentage on compensation, range low

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Defined contribution plan, percentage of matching contribution if compensation percentage below low range

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Defined contribution plan, percentage of matching contribution if compensation percentage between high range and low range

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Defined contribution plan, percentage of matching contribution if compensation percentage reaches average rate

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Number Of Retirement Plans Acquired

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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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Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

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Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

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Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

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Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

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Employee Benefits - Additional Information (Detail)	12 Months Ended
Employee Benefits - Additional Information (Detail)	Dec. 31, 2018 USD ($) retirement_plan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Percentage of matching contribution if compensation percentage below low range	100.00%
Matching participant's contribution, percentage on compensation	4.00%
Percentage of matching contribution if compensation percentage between high range and low range	75.00%
Matching participant's contribution, percentage on compensation, range low	4.00%
Matching participant's contribution, percentage on compensation, range high	8.00%
Percentage of employees eligible to accrue benefits under the defined plan	50.00%
Matching participant's contribution, average percentage on compensation	6.00%
Retirement liabilities	$ 227,172,000	$ 228,936,000
Capital in excess of par value related to Deferred Compensation Plan	22,200,000	22,500,000
Total cash surrender value of life insurance contracts	43,179,000	45,216,000
Pension cost (reversal of cost)	(8,000,000)
1% increase in accumulated postretirement benefit obligation	300,000
1% increase in postretirement expense	100,000
1% decrease in accumulated postretirement benefit obligation	300,000
1% decrease in postretirement expense	100,000
Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Retirement liabilities	43,600,000	43,000,000
U.K. Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension cost (reversal of cost)	2,800,000
Pension Plan [Member] \| U.S Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	562,043,000	602,783,000	$ 577,332,000
Retirement liabilities	46,519,000	49,981,000
Contribution to the plans	3,524,000	$ 5,123,000
Pension Plan [Member] \| U.S Plans [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities		20.00%
Pension Plan [Member] \| U.S Plans [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities		80.00%
Pension Plan [Member] \| U.S Plans [Member] \| Qualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	0
Pension Plan [Member] \| U.S Plans [Member] \| Nonqualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	3,500,000
Pension Plan [Member] \| Non-U.S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	957,935,000	$ 973,061,000	895,566,000
Retirement liabilities	114,705,000	80,694,000
Contribution to the plans	$ 18,238,000	36,645,000
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Alternative and other investments [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	5.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Alternative and other investments [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	10.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Real Estate [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	5.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Real Estate [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	20.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Equity Securities [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	15.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Equity Securities [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	40.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Fixed Income Securities [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	40.00%
Pension Plan [Member] \| Non-U.S. Plans [Member] \| Fixed Income Securities [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities	70.00%
Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 59,625,000	$ 82,714,000	$ 79,845,000
Contribution to the plans	$ 5,200,000
Frutarom Industries Ltd. [Member]
Defined Benefit Plan Disclosure [Line Items]
Number of retirement plans acquired \| retirement_plan	8
Frutarom Industries Ltd. [Member] \| Pension Plan [Member] \| U.S Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 2,100,000
Frutarom Industries Ltd. [Member] \| Pension Plan [Member] \| Non-U.S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 19,500,000