Investments - Schedule of Marketable Securities (Details) - USD ($) $ in Millions	Oct. 31, 2024	Jan. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 4,793	$ 5,782
Unrealized Gains	9	16
Unrealized Losses	(42)	(76)
Fair Value	4,760	5,722
Corporate notes and obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,511	3,014
Unrealized Gains	7	9
Unrealized Losses	(25)	(45)
Fair Value	2,493	2,978
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	410	583
Unrealized Gains	0	0
Unrealized Losses	(5)	(8)
Fair Value	405	575
Mortgage-backed obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	125	244
Unrealized Gains	0	1
Unrealized Losses	(6)	(9)
Fair Value	119	236
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,018	1,381
Unrealized Gains	2	5
Unrealized Losses	(4)	(7)
Fair Value	1,016	1,379
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96	139
Unrealized Gains	0	0
Unrealized Losses	(1)	(3)
Fair Value	95	136
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	527	213
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	527	213
Covered bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	27	81
Unrealized Gains	0	0
Unrealized Losses	(1)	(3)
Fair Value	26	78
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	79	127
Unrealized Gains	0	1
Unrealized Losses	0	(1)
Fair Value	$ 79	$ 127

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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