XML 86 R74.htm IDEA: XBRL DOCUMENT v3.10.0.1
Unearned Revenue and Performance Obligations (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Oct. 31, 2018
Oct. 31, 2017
Oct. 31, 2018
Oct. 31, 2017
Revenue from Contract with Customer [Abstract]        
Subscription revenue recognized that was included in total unearned revenue balance at beginning of period $ 547 $ 421 $ 1,200 $ 904
Subscriptions | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-11-01        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue is expected to be recognized from remaining performance obligations for subscription contracts $ 4,020   $ 4,020  
Subscriptions | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-11-01        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Recognition period 24 months   24 months  
Subscriptions | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue is expected to be recognized from remaining performance obligations for subscription contracts $ 5,900   $ 5,900