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Expected Capital Expenditures for Environmental Matters Due In One Year

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The number of assessments from the tax authorities of the State of Rio de Janeiro for unpaid Imposto sobre circulacao de Mercadorias e Servicos (or ICMS) taxes, a form of value-added tax in Brazil.

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Number of assessments from the tax authorities regarding ICMS taxes granted injunctions from enforcement

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Estimated annual cost to purchase electricity under a long-term contract from a production plant constructed and financed by a public utility district, cooperative, or other organization.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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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 loss contingency liability.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Number of pending claims pertaining to a loss contingency.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

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Commitments and Contingencies (Details) € in Millions	12 Months Ended
Commitments and Contingencies (Details) € in Millions	Dec. 31, 2018 USD ($) employee claim	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 EUR (€) employee claim	Dec. 31, 2000 assessment
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	$ 5,800,000
2020	5,000,000
2021	4,400,000
2022	3,600,000
2023	3,000,000
Thereafter	8,100,000
Total	29,900,000
Rent expense	6,700,000	$ 6,400,000	$ 6,900,000
Loss Contingencies [Line Items]
Capital expenditures for environmental matters	1,000,000
Capital expenditures for environmental matters, due in two years (less than)	1,000,000
Unfavorable Regulatory Action \| Raw Materials Assessment
Loss Contingencies [Line Items]
Number of assessments from the tax authorities regarding ICMS taxes \| assessment					2
Unfavorable Regulatory Action \| Electricity Assessment
Loss Contingencies [Line Items]
Number of assessments from the tax authorities regarding ICMS taxes \| assessment					4
Number of assessments from the tax authorities regarding ICMS taxes granted injunctions from enforcement \| assessment					2
Unfavorable Regulatory Action \| Electricity Assessment Four
Loss Contingencies [Line Items]
Liability recorded in the consolidated financial statements	0
Unfavorable Regulatory Action \| Malaucene Co-Employment
Loss Contingencies [Line Items]
Liability recorded in the consolidated financial statements	$ 0
Indemnification Agreement
Loss Contingencies [Line Items]
Number of pending claims \| claim	0			0
LTRI and PdM Subsidiaries \| Energy Cogeneration Steam Supply Agreement
Loss Contingencies [Line Items]
Minimum annual commitments	$ 7,500,000
SWM-B Brazilian Mill \| Transmission and Distribution of Energy Agreement
Loss Contingencies [Line Items]
Purchase of electrical energy, estimated annual cost	3,100,000
French Mills \| Electricity
Loss Contingencies [Line Items]
Purchase commitment, remaining amount committed	6,400,000
Calcium Carbonate \| PdM Subsidiary
Loss Contingencies [Line Items]
Purchase commitment, remaining amount committed	1,500,000
Calcium Carbonate, Through 2024 \| PdM Subsidiary
Loss Contingencies [Line Items]
Purchase commitment, remaining amount committed	9,100,000
Natural Gas \| SWM-B Brazilian Mill
Loss Contingencies [Line Items]
Purchase commitment, remaining amount committed	7,000,000
Maximum \| Unfavorable Regulatory Action \| Raw Materials Assessment 2
Loss Contingencies [Line Items]
Estimate of possible loss	11,200,000
Maximum \| Unfavorable Regulatory Action \| Electricity Assessment One
Loss Contingencies [Line Items]
Estimate of possible loss	4,600,000
Maximum \| Unfavorable Regulatory Action \| Electricity Assessment Two
Loss Contingencies [Line Items]
Estimate of possible loss	8,400,000
Maximum \| Unfavorable Regulatory Action \| Electricity Assessment Three
Loss Contingencies [Line Items]
Estimate of possible loss	700,000
Maximum \| Unfavorable Regulatory Action \| Electricity Assessment Four
Loss Contingencies [Line Items]
Estimate of possible loss	$ 9,200,000
Maximum \| Unfavorable Regulatory Action \| Malaucene Co-Employment
Loss Contingencies [Line Items]
Estimate of possible loss \| €				€ 1.3
Number of pending claims \| employee	18			18
Natural Gas \| French Mills
Loss Contingencies [Line Items]
Purchase commitment, remaining amount committed	$ 3,100,000
Biomass Consumption \| French Mills
Loss Contingencies [Line Items]
Minimum annual commitments	$ 1,700,000