Components of Accumulated Other Comprehensive Loss, Net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - Accumulated other comprehensive loss, net			$ (1,511)
Other comprehensive income (loss), unrecognized amounts on retirement benefits	$ (4)	$ 40	1	$ 62
Other comprehensive income (loss), foreign currency translation adjustment	221	(272)	308	(205)
Other comprehensive income (loss), unrealized gains on available-for-sale securities	81	38	119	71
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges	(2)	24	(6)	1
Other comprehensive income (loss)	296	(170)	422	(71)
Ending balance - Accumulated other comprehensive loss, net	(1,089)		(1,089)
Accumulated Other Comprehensive (Loss) Income, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance - unrecognized amounts on retirement benefits			(447)	(438)
Beginning balance - foreign currency translation adjustment			(1,675)	(1,092)
Beginning balance - unrealized gains (losses) on available-for-sale securities			585	615
Beginning balance - unrealized gains (losses) on cash flow hedges			26	7
Beginning balance - Accumulated other comprehensive loss, net			(1,511)	(908)
Other comprehensive income (loss), unrecognized amounts on retirement benefits			1	62
Other comprehensive income (loss), foreign currency translation adjustment			308	(205)
Other comprehensive income (loss), unrealized gains on available-for-sale securities			119	71
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges			(6)	1
Other comprehensive income (loss)			422	(71)
Ending balance - unrecognized amounts on retirement benefits	(446)	(376)	(446)	(376)
Ending balance - foreign currency translation adjustment	(1,367)	(1,297)	(1,367)	(1,297)
Ending balance - unrealized gains (losses) on available-for-sale securities	704	686	704	686
Ending balance - unrealized gains (losses) on cash flow hedges	20	8	20	8
Ending balance - Accumulated other comprehensive loss, net	$ (1,089)	$ (979)	$ (1,089)	$ (979)