Receivables and Allowances for Doubtful Accounts (Details) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Current and long-term receivables balances
Accounts receivable	$ 76,057	$ 67,259
Unbilled accounts receivable	31,567	30,647
Long-term receivables	3,672	7,559
Total receivables	111,296	105,465
Less allowance for doubtful accounts	0	(85)	0	(7,604)
Total receivables, net	$ 111,296	$ 105,380