Property and Equipment: (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 186,790	$ 182,950
Accumulated depreciation	(103,607)	(99,902)
Net property and equipment	83,183	83,048	[1]
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	74,846	73,390
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	60,747	60,334
Molds [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	25,120	24,133
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	17,799	17,518
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	2,390	2,298
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, cost	$ 5,888	$ 5,277

[1] December 31, 2011 balances were derived from audited consolidated financial statements.