Property and Equipment: (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 225,204	$ 213,001
Accumulated depreciation	(133,305)	(125,140)
Net property and equipment	91,899	87,861	[1]
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	91,947	84,317
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	64,316	64,238
Molds [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	32,737	30,813
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	22,403	21,625
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	3,655	3,552
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 10,146	$ 8,456

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