Segment Information - Revenue and Long-lived Assets by Region (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jan. 27, 2019	Oct. 28, 2018	Jul. 29, 2018	Apr. 29, 2018	Jan. 28, 2018	Oct. 29, 2017	Jul. 30, 2017	Apr. 30, 2017	Jan. 27, 2019	Jan. 28, 2018	Jan. 29, 2017
Revenues and Long-Lived Assets
Revenue	$ 2,205	$ 3,181	$ 3,123	$ 3,207	$ 2,911	$ 2,636	$ 2,230	$ 1,937	$ 11,716	$ 9,714	$ 6,910
Long-Lived Assets	1,512				1,071				1,512	1,071
Taiwan
Revenues and Long-Lived Assets
Revenue									3,360	2,991	2,546
Long-Lived Assets	137				58				137	58
China (including Hong Kong)
Revenues and Long-Lived Assets
Revenue									2,801	1,896	1,305
Long-Lived Assets	38				33				38	33
Other Asia Pacific
Revenues and Long-Lived Assets
Revenue									2,368	2,066	1,010
Long-Lived Assets	1				1				1	1
India
Revenues and Long-Lived Assets
Long-Lived Assets	44				40				44	40
United States
Revenues and Long-Lived Assets
Revenue									1,506	1,274	904
Long-Lived Assets	1,266				928				1,266	928
Europe
Revenues and Long-Lived Assets
Revenue									914	768	659
Long-Lived Assets	$ 26				$ 11				26	11
Other countries
Revenues and Long-Lived Assets
Revenue									$ 767	$ 719	$ 486