Fair Value (Details) - USD ($) $ in Thousands	Jul. 02, 2016	Jan. 02, 2016
Short-term investments:
Available-for-sale securities	$ 34,745	$ 94,498
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	23,786	24,905
Total Assets	453,473	480,094
Liabilities
Foreign currency exchange contracts		362
Total Liabilities		362
Money market funds [Member]
Assets
Cash equivalents	387,641	360,691
Corporate debt securities [Member]
Short-term investments:
Available-for-sale securities	1,998	34,829
Bank certificates of deposit [Member]
Assets
Cash equivalents	5,302
Short-term investments:
Available-for-sale securities	6,753	15,046
United States Treasury securities [Member]
Short-term investments:
Available-for-sale securities	21,418	36,286
United States government agency securities [Member]
Short-term investments:
Available-for-sale securities		4,152
Commercial paper [Member]
Assets
Cash equivalents	1,999
Short-term investments:
Available-for-sale securities	1,498	1,993
Marketable equity securities [Member]
Short-term investments:
Available-for-sale securities	3,078	2,192
Fair Value Measurements, Level 1 [Member]
Short-term investments:
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	23,786	24,905
Total Assets	435,923	428,226
Liabilities
Foreign currency exchange contracts		0
Total Liabilities		0
Fair Value Measurements, Level 1 [Member] \| Money market funds [Member]
Assets
Cash equivalents	387,641	360,691
Fair Value Measurements, Level 1 [Member] \| Corporate debt securities [Member]
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 1 [Member] \| Bank certificates of deposit [Member]
Assets
Cash equivalents	0
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 1 [Member] \| United States Treasury securities [Member]
Short-term investments:
Available-for-sale securities	21,418	36,286
Fair Value Measurements, Level 1 [Member] \| United States government agency securities [Member]
Short-term investments:
Available-for-sale securities		4,152
Fair Value Measurements, Level 1 [Member] \| Commercial paper [Member]
Assets
Cash equivalents	0
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 1 [Member] \| Marketable equity securities [Member]
Short-term investments:
Available-for-sale securities	3,078	2,192
Fair Value Measurements, Level 2 [Member]
Short-term investments:
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	0	0
Total Assets	17,550	51,868
Liabilities
Foreign currency exchange contracts		362
Total Liabilities		362
Fair Value Measurements, Level 2 [Member] \| Money market funds [Member]
Assets
Cash equivalents	0	0
Fair Value Measurements, Level 2 [Member] \| Corporate debt securities [Member]
Short-term investments:
Available-for-sale securities	1,998	34,829
Fair Value Measurements, Level 2 [Member] \| Bank certificates of deposit [Member]
Assets
Cash equivalents	5,302
Short-term investments:
Available-for-sale securities	6,753	15,046
Fair Value Measurements, Level 2 [Member] \| United States Treasury securities [Member]
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 2 [Member] \| United States government agency securities [Member]
Short-term investments:
Available-for-sale securities		0
Fair Value Measurements, Level 2 [Member] \| Commercial paper [Member]
Assets
Cash equivalents	1,999
Short-term investments:
Available-for-sale securities	1,498	1,993
Fair Value Measurements, Level 2 [Member] \| Marketable equity securities [Member]
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 3 [Member]
Short-term investments:
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	0	0
Total Assets	0	0
Liabilities
Foreign currency exchange contracts		0
Total Liabilities		0
Fair Value Measurements, Level 3 [Member] \| Money market funds [Member]
Assets
Cash equivalents	0	0
Fair Value Measurements, Level 3 [Member] \| Corporate debt securities [Member]
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 3 [Member] \| Bank certificates of deposit [Member]
Assets
Cash equivalents	0
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 3 [Member] \| United States Treasury securities [Member]
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 3 [Member] \| United States government agency securities [Member]
Short-term investments:
Available-for-sale securities		0
Fair Value Measurements, Level 3 [Member] \| Commercial paper [Member]
Assets
Cash equivalents	0
Short-term investments:
Available-for-sale securities	0	0
Fair Value Measurements, Level 3 [Member] \| Marketable equity securities [Member]
Short-term investments:
Available-for-sale securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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Fair value of financial and nonfinancial obligations.

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