Investments - Schedule of Marketable Securities (Details) - USD ($) $ in Millions	Apr. 30, 2026	Jan. 31, 2026
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 3,782	$ 4,304
Gross Unrealized Gains	15	36
Gross Unrealized Losses	(3)	0
Aggregate Fair Value	3,794	4,340
Included in Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	398
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	0	398
Included in Marketable securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,782	3,906
Gross Unrealized Gains	15	36
Gross Unrealized Losses	(3)	0
Aggregate Fair Value	3,794	3,942
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,491	1,820
Gross Unrealized Gains	5	11
Gross Unrealized Losses	0	0
Aggregate Fair Value	1,496	1,831
U.S. agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	215	265
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Aggregate Fair Value	215	266
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,890	1,874
Gross Unrealized Gains	10	22
Gross Unrealized Losses	(3)	0
Aggregate Fair Value	1,897	1,896
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		164
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Aggregate Fair Value		164
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	158	155
Gross Unrealized Gains	0	2
Gross Unrealized Losses	0	0
Aggregate Fair Value	158	157
Supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	28	26
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	$ 28	$ 26

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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