Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended												3 Months Ended		12 Months Ended
	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Oct. 01, 2011	Jul. 02, 2011	Apr. 02, 2011	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011	Dec. 29, 2012 Severance and related	Dec. 31, 2011 Severance and related	Jan. 01, 2011 Severance and related	Dec. 29, 2012 Lease termination	Dec. 31, 2011 Lease termination	Jan. 01, 2011 Lease termination	Dec. 29, 2012 Other	Dec. 31, 2011 Other	Jan. 01, 2011 Other	Dec. 29, 2012 2012 Restructuring Plan	Oct. 12, 2012 2012 Restructuring Plan employee	Dec. 29, 2012 2011 Restructuring Plan	Dec. 31, 2011 2011 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Approximate reduction in headcount																						110
Restructuring charges	$ 5,375	$ 0	$ 87	$ 556	$ 1,097	$ 1,760	$ 1,387	$ 1,835	$ 6,018	$ 6,079	$ 11										$ 5,400		$ 700	$ 6,900
Benefit related to re-occupying leased space which had previously been restructured									(118)	(996)		(104)	(175)		(14)	(821)		0						800
Restructuring Reserve [Roll Forward]
Beginning Balance				1,582				1,202	1,582	1,202	2,236	1,556	175	715	26	1,014	1,508	0	13	13
Restructuring charges									6,136	7,344	249	4,277	6,503	198	1,083	11	51	776	830	0
Non-cash adjustments										(269)	(238)		(269)	(295)			57
Cash payments									(4,176)	(5,699)	(1,045)	(3,356)	(4,678)	(443)	(302)	(178)	(602)	(518)	(843)
Adjustments to prior restructuring costs									(118)	(996)		(104)	(175)		(14)	(821)		0						800
Ending Balance	$ 3,424				$ 1,582				$ 3,424	$ 1,582	$ 1,202	$ 2,373	$ 1,556	$ 175	$ 793	$ 26	$ 1,014	$ 258	$ 0	$ 13