Commitments (Details) (USD $)	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Aggregate net minimum lease commitments under non-cancelable operating leases
2013	$ 1,388,000
2014	1,078,000
2015	969,000
2016	831,000
Later	3,873,000
Less: sublease contracts	307,000
Total minimum obligation	7,832,000
Rent expense primarily for office facilities	$ 1,000,000	$ 1,200,000	$ 1,400,000