Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 2,534	$ 197	$ 4,163	$ 921
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax of $(2), $(1), $(15), and $17	(466)	194	(411)	381
Net change in unrealized gains (losses) on available-for-sale debt securities:
Unrealized gains (losses), net of tax of $3, $0, $2, and $9	1	(6)	(40)	(8)
Reclassification adjustment for losses (gains) included in “Other income (expense), net,” net of tax of $0, $0, $0, and $0	1	2	1	5
Net unrealized gains (losses) on available-for-sale debt securities	2	(4)	(39)	(3)
Total other comprehensive income (loss)	(464)	190	(450)	378
Comprehensive income	$ 2,070	$ 387	$ 3,713	$ 1,299