Summary of Significant Accounting Policies (Cash, Cash Equivalents and Investments) (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Schedule of Investments [Line Items]
Cash and cash equivalents	$ 23,348	$ 36,312	$ 28,548	$ 34,144
Short-term investments	2,015	2,252
Long-term investments	10,479	10,033
Amortized cost basis of debt securities	12,660	12,445
Debt securities
Schedule of Investments [Line Items]
Cash and cash equivalents	0	0
Short-term investments	2,015	2,252
Long-term investments	10,479	10,033
Cash and money market accounts
Schedule of Investments [Line Items]
Cash and cash equivalents	23,348	36,312
Short-term investments	0	0
Long-term investments	$ 0	$ 0