Revenue Recognition Revenue Recognition - Narrative (Details) $ in Millions	12 Months Ended
	Jan. 31, 2021 USD ($) category	Jan. 31, 2020 USD ($)
Revenue from Contract with Customer [Abstract]
Number of revenue categories	3
Revenue from External Customer [Line Items]
Number of revenue categories	3
Contract with customer, liability, revenue recognized | $	$ 2,240	$ 1,800
Revenue, Performance Obligation, Description of Timing	three years
Minimum
Revenue from External Customer [Line Items]
Subscription payment terms	30 days
EBA payment terms	30 days
Maximum
Revenue from External Customer [Line Items]
Subscription payment terms	45 days
EBA payment terms	60 days