Basis of Presentation and Summary of Significant Accounting Policies - Deferred Revenue (Typed Dimensions) (Details) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-08-01	6 Months Ended
	Jul. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percentage	52.00%
Remaining performance obligation, expected timing	1 year