Property and Equipment: (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 224,118	$ 213,001
Accumulated depreciation	(135,586)	(125,140)
Net property and equipment	88,532	87,861	[1]
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	91,027	84,317
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	71,768	64,238
Molds [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	32,782	30,813
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	22,857	21,625
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	3,619	3,552
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 2,065	$ 8,456

[1] December 31, 2013 balances were derived from audited consolidated financial statements.