Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income	$ 573,000	$ 465,000
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income - Percentage	(2.00%)	2.00%
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	$ (278,000)	$ (86,000)
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ (6,061,000)	$ 5,000,000
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Percent	5.00%	(1.80%)
effective income tax rate reconciliation, valuation allowance due to foreign losses	$ (136,000)	$ (253,000)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount	$ 1,130,000	$ 329,000
Effective Income Tax Rate Reconciliation Amount - FDII	0	(194,000)
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	$ (1,430,000)	$ 436,000
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	(3.90%)	1.40%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	$ (261,000)	$ 180,000
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	0.80%	0.80%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	$ 252,000	$ (133,000)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent	(0.90%)	(0.60%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount	$ 232,000	$ 73,000
Effective Income Tax Rate Reconciliation Percent - FDII	0.00%	(0.80%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent	(0.80%)	0.30%
Effective Income Tax Rate Reconciliation Operating Loss Carryforwards Valuation Allowance For Foreign Country	0.50%	(1.10%)
Effective Income Tax Rate Reconciliation Capital Loss Carryforwards Valuation Allowance, Amount	$ 40,000	$ 0
Effective Income Tax Rate Reconciliation Capital Loss Carryforwards Valuation Allowance	(0.10%)	0.00%
Effective Income Tax Rate Reconciliation, Deduction, Amount	$ (6,540,000)	$ 4,026,000
Income Tax Expense (Benefit)	(6,540,000)	4,026,000
Goodwill, Impairment Loss	$ 13,696,000	$ 0
Effective Income Tax Rate Reconciliation, Percent	22.70%	16.90%
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	$ (28,861,000)	$ 23,811,000
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	$ (601,000)	0
Brazilian [Member]
Income Taxes [Line Items]
Effective income tax rate reconciliation social contribution on income	9.00%
Effective Income Tax Rate Reconciliation Federal Statutory Tax Rate Excluding Social Contribution On Income	25.00%
Effective Income Tax Rate Reconciliation Federal Statutory Tax Rate Including Social Contribution On Income	34.00%
Flexible Packaging Films [Member]
Income Taxes [Line Items]
Foreign Tax Credit - Brazil	$ 1,400,000	$ 400,000
Terphane Ltda [Member]
Income Taxes [Line Items]
Current Effective Tax Rate Including Social Contribution On Income	15.25%
LengthBrazilianTaxIncentive	13 years