Acquisition of Evolution Robotics, Inc. Acquisition of Evolution Robotics, Inc. (Details) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012	Dec. 31, 2011	Dec. 29, 2012 Evolution Robotics, Inc. (ER) [Member]	Oct. 02, 2012 Evolution Robotics, Inc. (ER) [Member]
Business Acquisition [Line Items]
Cash and cash equivalents				$ 356
Accounts receivable				1,635
Inventory				5,069
Other current assets				770
Deferred tax asset				1,740
Fixed assets				384
Goodwill	48,951	7,910	41,000	41,041
Intangible assets				27,000
Total Assets				77,995
Accounts payable				(2,793)
Accrued expenses				(51)
Accrued compensation				(91)
Other liabilities				(174)
Total consideration transferred				$ 74,886