Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 179	$ 234	$ 399	$ 751
Unrealized (loss) gain on available-for-sale debt securities, net of deferred tax	(2)		7	6
Total consolidated comprehensive income	177	234	406	757
Add: Comprehensive loss attributable to noncontrolling interests	0		0	12
Comprehensive income attributable to Illumina stockholders	$ 177	$ 234	$ 406	$ 769