Related-Party Transactions (Details) - Affiliated Entity $ in Millions	12 Months Ended
	Jan. 31, 2020 USD ($) employee board_seat	Jan. 31, 2019 USD ($)	Jan. 31, 2018 USD ($)
Related Party Transaction [Line Items]
Number of Company's board members that hold board seats in Foundation	1
Number of board seats in Foundation	3
Number of Company's employees that hold board seats in non-profit | employee	1
Number of Company's board members that hold board seats in non-profit | employee	1
Number of board seats in non-profit held by Company's employees and board members	3
Number of board seats in non-profit	8
Value of resources donated to related parties | $	$ 6	$ 15	$ 11
Value of donated subscriptions to related parties | $	$ 110	$ 253	$ 183