Financial Instruments (Tables)
 9 Months Ended
Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]  
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]
The following table summarizes the fair value of derivative instruments as of September 30, 2017 and December 31, 2016, which consist solely of foreign exchange contracts:
 
Asset Derivatives
 
Liability Derivatives
(Dollars in millions)
September 30, 2017
 
December 31, 2016
 
September 30, 2017
 
December 31, 2016
Derivatives designated as hedging instruments
$
295

 
$
15

 
$
15

 
$
196

Derivatives not designated as hedging instruments
95

 
155

 
75

 
158
Reclassification out of Accumulated Other Comprehensive Income [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) [Table Text Block]
The amount of gains and losses related to the Company's derivative financial instruments was as follows:
 
Quarter Ended September 30,
 
Nine Months Ended September 30,
(Dollars in millions)
2017
 
2016
 
2017
 
2016
Gain (loss) recorded in Accumulated other comprehensive loss
$
310

 
$
(7
)
 
$
440

 
$
188

(Gain) loss reclassified from Accumulated other comprehensive loss into Product sales (effective portion)
(24
)
 
32

 
(14
)
 
139
Other Income [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) [Table Text Block]
The effect on the Condensed Consolidated Statement of Operations of foreign exchange contracts not designated as hedging instruments was as follows:
 
Quarter Ended September 30,
 
Nine Months Ended September 30,
(Dollars in millions)
2017
 
2016
 
2017
 
2016
Gain recognized in Other income, net
$
10

 
$
19

 
$
50

 
$
49