Accumulated Other Comprehensive Income (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	$ (1,879)		$ (1,241)
Other comprehensive income (loss) before reclassifications	172		(461)
Amounts reclassified from AOCI	19		(20)
Other comprehensive income (loss), tax, portion attributable to parent	(17)		17
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(1,705)		(1,705)
Other Comprehensive Income (Loss), Net of Tax	174		(464)
Foreign Currency Translation Adjustment [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(1,323)		(654)
Other comprehensive income (loss) before reclassifications	177		(524)
Amounts reclassified from AOCI	0		0
Other comprehensive income (loss), tax, portion attributable to parent	(6)		26
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(1,152)		(1,152)
Other Comprehensive Income (Loss), Net of Tax	171		(498)
Deferred Gain (Loss) On Hedging Activities [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	12	$ (59)	47	$ 5
Other comprehensive income (loss) before reclassifications	23	23	31	(105)
Amounts reclassified from AOCI	15	47	(49)	78
Other comprehensive income (loss), tax, portion attributable to parent	(9)	(23)	12	10
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	41	$ (12)	41	$ (12)
Other Comprehensive Income (Loss), Net of Tax	29		(6)
Pension Liability Adjustment [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(607)		(630)
Other comprehensive income (loss) before reclassifications	(8)		9
Amounts reclassified from AOCI	4		29
Other comprehensive income (loss), tax, portion attributable to parent	0		(19)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(611)		(611)
Other Comprehensive Income (Loss), Net of Tax	(4)		19
Unrealized Gain (Loss) On Investments [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	39		(4)
Other comprehensive income (loss) before reclassifications	(20)		23
Amounts reclassified from AOCI	0		0
Other comprehensive income (loss), tax, portion attributable to parent	(2)		(2)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	17		17
Other Comprehensive Income (Loss), Net of Tax	$ (22)		$ 21