Change in Accounting for Retirement-Related Benefits (Tables)
 12 Months Ended
Jan. 30, 2016
Mark to Market (Tables) [Abstract]  
Schedule of Prior Period Adjustments Made to Consolidated Statements of Operations [Table Text Block]
Consolidated Statements of Operations
 
2014
 
2013
($ in millions, except per share data)
Previously Reported
 
As Adjusted
 
Effect of Change
 
Previously Reported
 
As Adjusted
 
Effect of Change
Pension
$
6

 
$
(48
)
 
$
(54
)
 
$
137

 
$
(41
)
 
$
(178
)
Income/(loss) before income taxes
(748
)
 
(694
)
 
54

 
(1,886
)
 
(1,708
)
 
178

Income tax expense/(benefit)
23

 
23

 
—

 
(498
)
 
(430
)
 
68

Net income/(loss)
$
(771
)
 
$
(717
)
 
54

 
$
(1,388
)
 
(1,278
)
 
$
110

Basic earnings/(loss) per common share
$
(2.53
)
 
$
(2.35
)
 
$
0.18

 
$
(5.57
)
 
$
(5.13
)
 
$
0.44

Diluted earnings/(loss) per common share
$
(2.53
)
 
$
(2.35
)
 
$
0.18

 
$
(5.57
)
 
$
(5.13
)
 
$
0.44
Schedule of Prior Period Adjustments Made to Consolidated Statements of Comprehensive Income/(Loss) [Table Text Block]
Consolidated Statements of Comprehensive Income/(Loss)
 
2014
 
2013
($ in millions)
Previously Reported
 
As Adjusted
 
Effect of Change
 
Previously Reported
 
As Adjusted
 
Effect of Change
Net income/(loss)
$
(771
)
 
$
(717
)
 
$
54

 
$
(1,388
)
 
$
(1,278
)
 
$
110

Reclassifications for amortization of net actuarial (gain)/loss
40

 
7

 
(33
)
 
108

 
(2
)
 
(110
)
Deferred tax valuation allowance
(169
)
 
(190
)
 
(21
)
 
—

 
—

 
—

Total other comprehensive income/(loss), net of tax
(437
)
 
(491
)
 
(54
)
 
490

 
380

 
(110
)
Total comprehensive income/(loss), net of tax
$
(1,208
)
 
$
(1,208
)
 
$
—

 
$
(898
)
 
$
(898
)
 
$
—
Schedule of Prior Period Adjustments Made to Consolidated Balance Sheet [Table Text Block]
Consolidated Balance Sheet
 
2014
($ in millions)
Previously Reported
 
As Adjusted
 
Effect of Change
Reinvested earnings/(accumulated deficit)
$
(1,779
)
 
$
(2,494
)
 
$
(715
)
Accumulated other comprehensive income/(loss)
(1,065
)
 
(350
)
 
715
Schedule of Prior Period Adjustments Made to Consolidated Statements Stockholders' Equity [Table Text Block]
Consolidated Statements of Stockholders' Equity
 
2014
 
2013
($ in millions)
Previously Reported
 
As Adjusted
 
Effect of Change
 
Previously Reported
 
As Adjusted
 
Effect of Change
Reinvested earnings/(loss)
 
 
 
 
 
 
 
 
 
 
 
   Beginning balance
$
(1,008
)
 
$
(1,777
)
 
$
(769
)
 
$
380

 
$
(499
)
 
$
(879
)
   Net income/(loss)
(771
)
 
(717
)
 
54

 
(1,388
)
 
(1,278
)
 
110

   Ending balance
$
(1,779
)
 
$
(2,494
)
 
$
(715
)
 
$
(1,008
)
 
$
(1,777
)
 
$
(769
)
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated other comprehensive income/(loss)
 
 
 
 
 
 
 
 
 
 
 
   Beginning balance
$
(628
)
 
$
141

 
$
769

 
$
(1,118
)
 
$
(239
)
 
$
879

   Other comprehensive income/(loss)
(437
)
 
(491
)
 
(54
)
 
490

 
380

 
(110
)
   Ending balance
$
(1,065
)
 
$
(350
)
 
$
715

 
$
(628
)
 
$
141

 
$
769
Schedule of Prior Period Adjustments Made to Consolidated Statements of Cash Flows [Table Text Block]
Consolidated Statements of Cash Flows
 
2014
 
2013
($ in millions)
Previously Reported
 
As Adjusted
 
Effect of Change
 
Previously Reported
 
As Adjusted
 
Effect of Change
Cash flows from operating activities:
 
 
 
 

 
 
 
 
 

Net income/(loss)
$
(771
)
 
$
(717
)
 
$
54

 
$
(1,388
)
 
$
(1,278
)
 
$
110

Benefit plans
(24
)
 
(78
)
 
(54
)
 
70

 
(108
)
 
(178
)
Other comprehensive income tax benefits
—

 
—

 
—

 
(303
)
 
(250
)
 
53

Deferred taxes
$
3

 
$
3

 
$
—

 
$
(164
)
 
$
(149
)
 
$
15