Segment Information 1 (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 9 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Segment information        
Revenue $ 1,091 $ 1,128 $ 3,239 $ 3,328
Income from continuing operations before interest and income taxes 318 321 951 885
Reconciliation of segment profit to income from continuing operations before income taxes        
Segment profit 318 321 951 885
Software development costs capitalized 0 (1) 0 (32)
Share-based compensation expense 23 23 65 63
Other expenses, net (6) [1] 9 [1] 2 [1] 131 [2]
Interest expense, net 12 15 38 39
Income from continuing operations before income taxes 306 306 913 846
Purchased Software Products [Member]        
Reconciliation of segment profit to income from continuing operations before income taxes        
Amortization of intangible assets 28 28 87 87
Other Intangible Assets [Member]        
Reconciliation of segment profit to income from continuing operations before income taxes        
Amortization of intangible assets 14 19 45 48
Internally Developed Software Products [Member]        
Reconciliation of segment profit to income from continuing operations before income taxes        
Amortization of intangible assets 34 41 117 117
Mainframe Solutions [Member]        
Segment information        
Revenue 596 622 1,820 1,865
Expenses 248 241 717 716
Income from continuing operations before interest and income taxes 348 381 1,103 1,149
Segment operating margin 58.00% 61.00% 61.00% 62.00%
Depreciation 10 13 33 40
Reconciliation of segment profit to income from continuing operations before income taxes        
Segment profit 348 381 1,103 1,149
Enterprise Solutions [Member]        
Segment information        
Revenue 405 412 1,151 1,174
Expenses 347 357 999 1,045
Income from continuing operations before interest and income taxes 58 55 152 129
Segment operating margin 14.00% 13.00% 13.00% 11.00%
Depreciation 7 8 21 25
Reconciliation of segment profit to income from continuing operations before income taxes        
Segment profit 58 55 152 129
Services [Member]        
Segment information        
Revenue 90 94 268 289
Expenses 85 90 256 268
Income from continuing operations before interest and income taxes 5 4 12 21
Segment operating margin 6.00% 4.00% 4.00% 7.00%
Depreciation 0 0 0 0
Reconciliation of segment profit to income from continuing operations before income taxes        
Segment profit 5 4 12 21
Total Reportable Segments [Member]        
Segment information        
Revenue 1,091 1,128 3,239 3,328
Expenses 680 688 1,972 2,029
Income from continuing operations before interest and income taxes 411 440 1,267 1,299
Segment operating margin 38.00% 39.00% 39.00% 39.00%
Depreciation 17 21 54 65
Reconciliation of segment profit to income from continuing operations before income taxes        
Segment profit $ 411 $ 440 $ 1,267 $ 1,299
[1] Other expenses, net consists of costs associated with the Fiscal 2014 Plan, certain foreign exchange derivative hedging gains and losses, and other miscellaneous costs.
[2] Other expenses, net consists of approximately $131 million of costs associated with the Fiscal 2014 Plan, certain foreign exchange derivative hedging gains and losses, and other miscellaneous costs.