v3.8.0.1

Segment Information, Geographic Data, and Significant Customers - Summary of Operating Performance and Assets by Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	Jan. 01, 2017	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Segment Reporting Information [Line Items]
Segment revenues	$ 778	$ 714	$ 662	$ 598	$ 619	$ 607	$ 600	$ 572	$ 2,752	$ 2,398	$ 2,220
Segment depreciation and amortization									156	141	127
Segment operating income (loss)									606	587	613
Segment assets	5,257				4,281				5,257	4,281	3,688
Segment capital expenditures									310	260	143
Eliminations [Member]
Segment Reporting Information [Line Items]
Segment revenues									(8)	(30)
Segment depreciation and amortization									(3)	(1)
Segment operating income (loss)									2	(16)
Segment assets	(11)				(66)				(11)	(66)	(1)
Operating Segments [Member] | Core Illumina [Member]
Segment Reporting Information [Line Items]
Segment revenues									2,754	2,428	2,220
Segment depreciation and amortization									153	138	127
Segment operating income (loss)									696	684	621
Segment assets	5,223				4,167				5,223	4,167	3,658
Segment capital expenditures									306	238	142
Operating Segments [Member] | Consolidated VIEs [Member]
Segment Reporting Information [Line Items]
Segment revenues									6
Segment depreciation and amortization									6	4
Segment operating income (loss)									(92)	(81)	(8)
Segment assets	$ 45				$ 180				45	180	31
Segment capital expenditures									$ 4	$ 22	$ 1

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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