Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Dec. 28, 2014		Dec. 29, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 29,425	[1]	$ 35,812	[1]
Total assets	29,425		35,812
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	874		35,812	[1]
Total assets	874		35,812
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	28,551		0	[1]
Total assets	28,551		0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0	[1]	0	[1]
Total assets	$ 0		$ 0

[1] Money market funds are presented as a part of cash and cash equivalents on the accompanying consolidated balance sheets as of December 28, 2014 and December 29, 2013.