Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Stock-based expenses	$ 566	$ 543	$ 1,648	$ 1,274
Unrealized gain	1,000		1,600
Publicly traded securities
Unrealized gain	997	(84)	1,620	132
Cost of revenues
Amortization of intangibles acquired through business combinations	169	157	494	280
Stock-based expenses	65	54	180	143
Research and development
Stock-based expenses	181	169	531	348
Marketing and sales
Amortization of intangibles acquired through business combinations	114	109	344	242
Stock-based expenses	242	249	718	625
General and administrative
Stock-based expenses	$ 78	$ 71	$ 219	$ 158