Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011
Sales return liability [Roll Forward]
Balance at beginning of year	$ 4,402	$ 2,944
Additions that reduce net sales	33,082	29,891
Deductions from reserves	(32,231)	(28,329)
Balance at end of period	5,253	4,506
Warranty on beds, description	20-year
Customer participation term	18 years
Accrued warranty liabilities [Roll Forward]
Balance at beginning of year	6,310	5,744
Additions charged to costs and expenses for current-year sales	3,023	3,902
Deductions from reserves	(3,785)	(3,573)
Changes in liability for pre-existing warranties during the current year, including expirations	484	(882)
Balance at end of period	$ 5,064	$ 6,955