Document and Entity Information Document (USD $) Share data in Millions, unless otherwise specified	12 Months Ended
	Dec. 29, 2013	Jan. 31, 2014	Jun. 30, 2013
Document and Entity Information [Abstract]
Entity Registrant Name	Illumina Inc
Entity Central Index Key	0001110803
Current Fiscal Year End Date	--12-29
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 29, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		128.2
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 6,900,000,000