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Major Customers (Details) - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net sales | Phillip Morris, British American, and Japan Tobacco
Concentration Risk [Line Items]
Concentration risk, percentage		10.00%	11.00%
Engineered Papers | Accounts receivable
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%

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