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Collaboration Agreements (Royalty Revenues under the Collaboration Agreement with GSK) (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 03, 2020	Dec. 28, 2018	Dec. 29, 2017
Collaborative Arrangements with Glaxo Smith Kline
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty expense	$ 31.3	$ 24.0	$ 12.4
Collaborative Arrangement with GlaxoSmithKline
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration agreement percent of royalty on net sale	3.00%

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- Definition

Collaboration Agreement, Percent Of Royalty On Net Sale

+ References

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+ References

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- Definition

Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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