Investments - Summary of Marketable Securities (Detail) - USD ($) $ in Millions	Jan. 31, 2026	Jan. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 4,304	$ 6,638
Gross Unrealized Gains	36	17
Gross Unrealized Losses	0	(4)
Aggregate Fair Value	4,340	6,651
Included in Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	398	177
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	398	177
Included in Marketable securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,906	6,461
Gross Unrealized Gains	36	17
Gross Unrealized Losses	0	(4)
Aggregate Fair Value	3,942	6,474
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,820	2,069
Gross Unrealized Gains	11	4
Gross Unrealized Losses	0	(1)
Aggregate Fair Value	1,831	2,072
U.S. agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	265	634
Gross Unrealized Gains	1	2
Gross Unrealized Losses	0	0
Aggregate Fair Value	266	636
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,874	3,532
Gross Unrealized Gains	22	11
Gross Unrealized Losses	0	(3)
Aggregate Fair Value	1,896	3,540
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	164	294
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	164	294
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	155	104
Gross Unrealized Gains	2	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	157	104
Supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	26	5
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Aggregate Fair Value	$ 26	$ 5

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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