Stockholders' Equity (Tables)
 12 Months Ended
Jan. 28, 2017
Stockholders' Equity Note [Abstract]  
Schedule of Accumulated Other Comprehensive Income/(Loss)
($ in millions)
 
Net Actuarial Gain/(Loss)
 
Prior Service Credit/(Cost)
 
Foreign Currency Translation
 
Gain/(Loss) on Cash Flow Hedges
 
Accumulated Other Comprehensive Income/(Loss)
January 31, 2015
 
$
(308
)
 
$
(40
)
 
$
(2
)
 
$
—

 
$
(350
)
Current period change
 
(115
)
 
2

 
—

 
(28
)
 
(141
)
January 30, 2016
 
$
(423
)
 
$
(38
)
 
$
(2
)
 
$
(28
)
 
$
(491
)
Current period change
 
2

 
5

 
—

 
11

 
18

January 28, 2017
 
$
(421
)
 
$
(33
)
 
$
(2
)
 
$
(17
)
 
$
(473
)