Accumulated Other Comprehensive Income (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	$ (1,947)	$ (2,146)
Other comprehensive income (loss) before reclassifications	(137)	1
Amounts reclassified from AOCI	(42)	0
Other comprehensive income (loss), tax, portion attributable to parent	(12)	7
Other Comprehensive Income (Loss), Net of Tax	(191)	8
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,138)	(2,138)
Foreign Currency Translation Adjustment [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(1,401)	(1,626)
Other comprehensive income (loss) before reclassifications	(145)	57
Amounts reclassified from AOCI	(73)	(73)
Other comprehensive income (loss), tax, portion attributable to parent	(10)	13
Other Comprehensive Income (Loss), Net of Tax	(228)	(3)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(1,629)	(1,629)
Deferred Gain (Loss) On Hedging Activities [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(7)	(15)
Other comprehensive income (loss) before reclassifications	(40)	(62)
Amounts reclassified from AOCI	19	51
Other comprehensive income (loss), tax, portion attributable to parent	2	0
Other Comprehensive Income (Loss), Net of Tax	(19)	(11)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(26)	(26)
Pension Liability Adjustment [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(522)	(523)
Other comprehensive income (loss) before reclassifications	3	(6)
Amounts reclassified from AOCI	12	22
Other comprehensive income (loss), tax, portion attributable to parent	(3)	(3)
Other Comprehensive Income (Loss), Net of Tax	12	13
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(510)	(510)
Unrealized Gain (Loss) On Investments [Member]
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(17)	18
Other comprehensive income (loss) before reclassifications	45	12
Amounts reclassified from AOCI	0	0
Other comprehensive income (loss), tax, portion attributable to parent	(1)	(3)
Other Comprehensive Income (Loss), Net of Tax	44	9
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	$ 27	$ 27