Components of Accumulated Other Comprehensive Loss, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 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	5	$ 22
Other comprehensive income (loss), foreign currency translation adjustment	87	67
Other comprehensive income (loss), unrealized gains on available-for-sale securities	38	33
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges	(4)	(23)
Other comprehensive income (loss)	126	99
Ending balance - Accumulated other comprehensive loss, net	(1,385)
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	5	22
Other comprehensive income (loss), foreign currency translation adjustment	87	67
Other comprehensive income (loss), unrealized gains on available-for-sale securities	38	33
Other comprehensive income (loss), unrealized gains (losses) on cash flow hedges	(4)	(23)
Other comprehensive income (loss)	126	99
Ending balance - unrecognized amounts on retirement benefits	(442)	(416)
Ending balance - foreign currency translation adjustment	(1,588)	(1,025)
Ending balance - unrealized gains (losses) on available-for-sale securities	623	648
Ending balance - unrealized gains (losses) on cash flow hedges	22	(16)
Ending balance - Accumulated other comprehensive loss, net	$ (1,385)	$ (809)