Significant Accounting Policies (Property, Plant and Equipment) (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Cost of property repairs and maintenance	$ 16,900	$ 16,500	$ 14,800
Depreciation	15,800	15,000	14,300
Cost of goods sold, depreciation	15,400	14,600	14,100
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Interest costs capitalized	$ 0	$ 0	$ 263
Minimum [Member] | Land and Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Capitalized maintenance cost, amortization period	12 months
Maximum [Member] | Land and Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	39 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years