Commitments and Contingencies (Details) (USD $)	12 Months Ended				1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended
	Dec. 31, 2011	Jan. 01, 2011	Jan. 02, 2010	Dec. 31, 2011 Headquarters leases quarter	Apr. 01, 2006 400 WCC Y	Dec. 31, 2011 400 WCC	Apr. 05, 2008 200 WCC Y	Dec. 31, 2011 200 WCC
Commitments and Contingencies
Rent expense under operating leases	$ 4,500,000	$ 5,000,000	$ 5,100,000
Minimum annual future rentals
2012	6,630,000
2013	3,347,000
2014	1,664,000
2015	1,515,000
2016	1,518,000
Thereafter	2,996,000
Total minimum lease payments	17,670,000
Minimum sublease rental income	(3,795,000)
Total net minimum lease payments	13,875,000
Operating Leases
Lease term (in years)					7		5
Purchase option price for buildings (in dollars)						44,300,000		50,100,000
Basis spread on variable rate to compute base rent for buildings (as a percent)						1.10%		1.55%
Description of variable rate basis to compute base rent for buildings	three-month LIBOR					three-month LIBOR		three-month LIBOR
Base rent at assumed average variable rate						900,000		1,300,000
Assumed average variable rate basis to compute base rent for the buildings (as a percent)						0.56%		0.56%
Minimum unencumbered cash and highly rated short-term investments to be maintained by the entity				75,000,000
Threshold unencumbered cash and highly-rated short-term investments to trigger restriction on funded debt to EBITDAR				150,000,000
Number of prior fiscal quarters to maintain maximum ratio of funded debt to EBITDAR				4
Numerator for maximum funded debt to EBITDAR ratio				2
Denominator for maximum funded debt to EBITDAR ratio				1
Contingent liability on sale of leased property to third party (in dollars)						35,300,000		40,000,000
Fair value of guaranteed residual value at inception of lease					$ 1,000,000		$ 1,200,000