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Commitments and Contingencies (Details) $ in Thousands			12 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Jan. 28, 2014 patent	Jan. 16, 2014 patent	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jan. 02, 2016 USD ($) patent	Jan. 03, 2015 patent
Operating Leases
Rent expense under operating leases			$ 5,500	$ 4,700	$ 4,600
Minimum annual future rentals
2018			5,807
2019			4,278
2020			3,539
2021			3,016
2022			2,804
Thereafter			5,416
Total minimum lease payments			24,860
Investment Commitment
Unfunded investment commitment			3,800	$ 2,800
High end of range \| Other assets
Investment Commitment
Unfunded investment commitment			$ 10,000
Cresta Technology
Patent Litigation
Number of patents allegedly infringed \| patent	3	6
Number of creditors assuming ownership of Cresta Patents \| patent	1
Number of patents with validity challenged \| patent					2	2