Shareholders' Equity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	$ (1,241)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,146)	$ (1,241)
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(984)	(953)
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	(654)	269
Net realized gains (losses)	23	0
Other Comprehensive Income (Loss), Tax	(11)	30
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(972)	(923)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(1,626)	(654)
Deferred Gain (Loss) On Hedging Activities [Member]
Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(53)	(119)
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	47	5
Net realized gains (losses)	(46)	187
Other Comprehensive Income (Loss), Tax	37	(26)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(62)	42
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(15)	47
Pension Liability Adjustment [Member]
Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax	87	(485)
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	(630)	(330)
Net realized gains (losses)	67	21
Other Comprehensive Income (Loss), Tax	(47)	164
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	107	(300)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(523)	(630)
Unrealized Gain (Loss) On Investments [Member]
Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax	20	(11)
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	(4)	(1)
Net realized gains (losses)	0	6
Other Comprehensive Income (Loss), Tax	2	2
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	22	(3)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	18	(4)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(930)	(1,568)
Accumulated other comprehensive income (loss)
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	(1,241)	(57)
Net realized gains (losses)	44	214
Other Comprehensive Income (Loss), Tax	(19)	170
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(905)	(1,184)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	$ (2,146)	$ (1,241)