Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income	$ 465,000	$ 357,000
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income - Percentage	2.00%	1.50%
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	$ (86,000)	$ (100,000)
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 5,000,000	$ 4,925,000
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Percent	(1.80%)	(0.90%)
effective income tax rate reconciliation, valuation allowance due to foreign losses	$ (253,000)	$ (362,000)
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	$ 329,000	$ 221,000
Effective Income Tax Rate Reconciliation Amount - FDII	(194,000)	(153,000)
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	$ (436,000)	$ 211,000
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	1.40%	0.90%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	$ 180,000	$ 321,000
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	0.80%	1.40%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	$ (133,000)	$ 173,000
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent	(0.60%)	0.70%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount	$ 73,000.000	$ 84,000.000
Effective Income Tax Rate Reconciliation Percent - FDII	(0.80%)	(0.70%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent	0.30%	0.40%
Effective Income Tax Rate Reconciliation Amount - GILTI	$ 0.000	$ 32,000.000
Effective Income Tax Rate Reconciliation Percent - GILTI	0.00%	0.10%
Effective Income Tax Rate Reconciliation Operating Loss Carryforwards Valuation Allowance For Foreign Country	(1.10%)	(1.50%)
Effective Income Tax Rate Reconciliation, Deduction, Amount	$ (4,026,000.000)	$ (5,287,000.000)
Income Tax Expense (Benefit)	$ 4,026,000	$ 5,287,000
Effective Income Tax Rate Reconciliation, Percent	16.90%	22.50%
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	$ 23,811,000	$ 23,451,000
Income Tax Examination, Interest Accrued	$ 200,000
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	$ 400,000	$ 200,000
Terphane Ltda [Member]
Income Taxes [Line Items]
Current Effective Tax Rate Including Social Contribution On Income	15.25%
LengthBrazilianTaxIncentive	10 years