Investments - Schedule of Marketable Securities (Details) - USD ($) $ in Millions	Apr. 30, 2024	Jan. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 7,802	$ 5,782
Unrealized Gains	4	16
Unrealized Losses	(94)	(76)
Fair Value	7,712	5,722
Corporate notes and obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,751	3,014
Unrealized Gains	2	9
Unrealized Losses	(54)	(45)
Fair Value	3,699	2,978
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	552	583
Unrealized Gains	0	0
Unrealized Losses	(11)	(8)
Fair Value	541	575
Mortgage-backed obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	272	244
Unrealized Gains	0	1
Unrealized Losses	(10)	(9)
Fair Value	262	236
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,655	1,381
Unrealized Gains	1	5
Unrealized Losses	(11)	(7)
Fair Value	1,645	1,379
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	137	139
Unrealized Gains	0	0
Unrealized Losses	(3)	(3)
Fair Value	134	136
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,223	213
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	1,223	213
Covered bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	72	81
Unrealized Gains	0	0
Unrealized Losses	(3)	(3)
Fair Value	69	78
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	140	127
Unrealized Gains	1	1
Unrealized Losses	(2)	(1)
Fair Value	$ 139	$ 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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