Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Stock-based expenses	$ 578	$ 388	$ 1,082	$ 731
Tax benefit from intra-entity transfer of intangible property	2,000
Cost of revenues
Amortization of intangibles acquired through business combinations	166	62	325	123
Stock-based expenses	63	46	115	89
Research and development
Stock-based expenses	184	98	350	179
Marketing and sales
Amortization of intangibles acquired through business combinations	118	65	230	133
Stock-based expenses	253	199	476	376
General and administrative
Stock-based expenses	$ 78	$ 45	$ 141	$ 87