Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 3,561	$ 1,629
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax of $21 and $(1)	(8)	59
Net change in unrealized gains (losses) on available-for-sale debt securities:
Unrealized gains (losses), net of tax of $9 and $0	32	(44)
Reclassification adjustment for losses (gains) included in “Other income (expense), net,” net of tax of $0 and $0	1	2
Net unrealized gains (losses) on available-for-sale debt securities	33	(42)
Total other comprehensive income (loss)	25	17
Comprehensive income	$ 3,586	$ 1,646