The number of positions eliminated during the period as a result of restructuring activities.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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No definition available.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Business Restructuring - Additional Information (Detail)	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($) Employees	Dec. 31, 2017 USD ($)	Jun. 30, 2020 USD ($) Employees	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Restructuring Cost And Reserve [Line Items]
Restructuring costs	$ 225,000	$ 450,000			$ 582,000	$ 1,183,000
Netherlands [Member]
Restructuring Cost And Reserve [Line Items]
Number positions eliminated \| Employees			5
Severance costs			$ 396,000
Germany [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs					$ 2,392,000
Germany [Member] \| Surfactants [Member] \| Asset and Spare Part [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs							$ 1,404,000
Fieldsboro, NJ [Member]
Restructuring Cost And Reserve [Line Items]
Business restructuring			251,000	$ 915,000
Longford Mills [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Number positions eliminated \| Employees					30
Business restructuring					$ 7,987,000
Early Termination of Lease Expenses [Member] \| Netherlands [Member]
Restructuring Cost And Reserve [Line Items]
Business restructuring			$ 79,000
Cumulative Decommissioning Costs [Member] \| Germany [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs					988,000
Decommissioning Costs [Member] \| Germany [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs	0	208,000			79,000	395,000
Decommissioning Costs [Member] \| Longford Mills [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Business restructuring	$ 225,000	$ 200,000			503,000	$ 521,000
Termination Benefits [Member] \| Longford Mills [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Business restructuring					1,644,000
Other Expense [Member] \| Longford Mills [Member] \| Surfactants [Member]
Restructuring Cost And Reserve [Line Items]
Business restructuring					$ 6,343,000