Benefit Plans (Amounts Recognized in the Consolidated Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Accrued benefit liability—noncurrent	$ (1,342)	$ (1,310)
U.S. Defined Benefit Plans
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Noncurrent assets	0	0
Accrued benefit liability—current	0	0
Accrued benefit liability—noncurrent	(174)	(118)
Net amount recognized at end of year	(174)	(118)
Foreign Defined Benefit Plans
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Noncurrent assets	51	23
Accrued benefit liability—current	(4)	(4)
Accrued benefit liability—noncurrent	(1,138)	(1,163)
Net amount recognized at end of year	$ (1,091)	$ (1,144)