Earnings/(Loss) per Share (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
3 Months Ended
Apr. 30, 2016
May. 02, 2015
Earnings Per Share [Abstract]    
Net income/(loss) $ (68) $ (150)
Weighted average common shares outstanding (basic shares) 307.2 305.5
Weighted average shares assuming dilution (diluted shares) 307.2 305.5
Basic (in dollars per share) $ (0.22) $ (0.49)
Diluted (in dollars per share) $ (0.22) $ (0.49)
Stock options, restricted stock awards and warrant 35.2 31.6