Investments - Schedule of Marketable Securities (Details) - USD ($) $ in Millions	Jan. 31, 2025	Jan. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 5,215	$ 5,782
Unrealized Gains	9	16
Unrealized Losses	(40)	(76)
Fair Value	5,184	5,722
Corporate notes and obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,574	3,014
Unrealized Gains	6	9
Unrealized Losses	(23)	(45)
Fair Value	2,557	2,978
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	546	583
Unrealized Gains	0	0
Unrealized Losses	(4)	(8)
Fair Value	542	575
Mortgage-backed obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	128	244
Unrealized Gains	0	1
Unrealized Losses	(6)	(9)
Fair Value	122	236
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,218	1,381
Unrealized Gains	3	5
Unrealized Losses	(4)	(7)
Fair Value	1,217	1,379
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	108	139
Unrealized Gains	0	0
Unrealized Losses	(1)	(3)
Fair Value	107	136
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	506	213
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	506	213
Covered bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	29	81
Unrealized Gains	0	0
Unrealized Losses	(2)	(3)
Fair Value	27	78
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	106	127
Unrealized Gains	0	1
Unrealized Losses	0	(1)
Fair Value	$ 106	$ 127