Cash, Cash Equivalents and Investments (Details 3) - USD ($) $ in Thousands	Jan. 02, 2016	Jan. 03, 2015
Short-term investments
Amortized Cost	$ 94,287	$ 90,404
Gross Unrealized Gains	380	91
Gross Unrealized Losses	(169)	(50)
Fair Value	94,498	90,445
Corporate debt securities [Member]
Short-term investments
Amortized Cost	34,905	34,919
Gross Unrealized Gains	1	6
Gross Unrealized Losses	(77)	(31)
Fair Value	34,829	34,894
Bank certificates of deposit [Member]
Short-term investments
Amortized Cost	15,049	21,900
Gross Unrealized Gains	1	10
Gross Unrealized Losses	(4)	0
Fair Value	15,046	21,910
United States Treasury securities [Member]
Short-term investments
Amortized Cost	36,372	19,375
Gross Unrealized Gains	2	12
Gross Unrealized Losses	(88)	(13)
Fair Value	36,286	19,374
United States government agency securities [Member]
Short-term investments
Amortized Cost	4,151	9,209
Gross Unrealized Gains	1	3
Gross Unrealized Losses	0	(4)
Fair Value	4,152	9,208
Commercial paper [Member]
Short-term investments
Amortized Cost	1,993	3,184
Gross Unrealized Gains	0	4
Gross Unrealized Losses	0	(2)
Fair Value	1,993	3,186
Marketable debt securities [Member]
Short-term investments
Amortized Cost	92,470	88,587
Gross Unrealized Gains	5	35
Gross Unrealized Losses	(169)	(50)
Fair Value	92,306	88,572
Marketable equity securities [Member]
Short-term investments
Amortized Cost	1,817	1,817
Gross Unrealized Gains	375	56
Gross Unrealized Losses	0	0
Fair Value	$ 2,192	$ 1,873

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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