Debt - Schedule of Interest Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Debt Disclosure [Abstract]
Contractual interest expense	$ 69	$ 24	$ 128	$ 72
Amortization of debt discounts and debt issuance costs	3	1	17	3
Debt interest expense	$ 72	$ 25	$ 145	$ 75