Receivables and Allowances for Doubtful Accounts (Details) (USD $) In Thousands, unless otherwise specified	Sep. 28, 2013	Dec. 29, 2012
Current and long-term receivables balances
Accounts receivable	$ 61,906	$ 67,259
Installment contract receivables, short-term	40,134	30,647
Long-term receivables	3,994	7,559
Total receivables	106,034	105,465
Less allowance for doubtful accounts	(144)	(85)
Total receivables, net	$ 105,890	$ 105,380