Fair Value (Details) - USD ($) $ in Thousands	Oct. 01, 2016	Jan. 02, 2016
Short-term investments:
Available-for-sale securities	$ 8,503	$ 94,498
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	25,657	24,905
Foreign Currency Contract, Asset, Fair Value Disclosure	349
Total Assets	331,580	480,094
Liabilities
Foreign currency exchange contracts		362
Total Liabilities		362
Money market funds [Member]
Assets
Cash equivalents	297,071	360,691
Corporate debt securities [Member]
Short-term investments:
Available-for-sale securities	400	34,829
Bank certificates of deposit [Member]
Short-term investments:
Available-for-sale securities	2,000	15,046
United States Treasury securities [Member]
Short-term investments:
Available-for-sale securities	2,000	36,286
United States government agency securities [Member]
Short-term investments:
Available-for-sale securities		4,152
Commercial paper [Member]
Short-term investments:
Available-for-sale securities	1,000	1,993
Marketable equity securities [Member]
Short-term investments:
Available-for-sale securities	3,103	2,192
Fair Value Measurements, Level 1 [Member]
Short-term investments:
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	25,657	24,905
Foreign Currency Contract, Asset, Fair Value Disclosure	0
Total Assets	327,831	428,226
Liabilities
Foreign currency exchange contracts		0
Total Liabilities		0
Fair Value Measurements, Level 1 [Member] \| Money market funds [Member]
Assets
Cash equivalents	297,071	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]
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	2,000	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]
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	3,103	2,192
Fair Value Measurements, Level 2 [Member]
Short-term investments:
Trading securities held in Non-Qualified Deferred Compensation plan, or NQDC	0	0
Foreign Currency Contract, Asset, Fair Value Disclosure	349
Total Assets	3,749	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	400	34,829
Fair Value Measurements, Level 2 [Member] \| Bank certificates of deposit [Member]
Short-term investments:
Available-for-sale securities	2,000	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]
Short-term investments:
Available-for-sale securities	1,000	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
Foreign Currency Contract, Asset, Fair Value Disclosure	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]
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]
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)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: 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.

+ References

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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