CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	Common stock	Additional paid-in capital	Treasury stock at cost	Retained earnings	Accumulated other comprehensive income (loss)
Beginning balance at Dec. 31, 2017		$ 2	$ 15,293	$ (21,892)	$ 13,929	$ 717
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		0
Common stock repurchased/forfeited		0
Common stock and stock-based awards issued			67
Tax withholdings related to net share settlements of restricted stock units and awards			(153)
Stock-based compensation			271
Other			0
Common stock repurchased				(2,000)
Net income	$ 1,049				1,049
Dividends and dividend equivalents declared					0
Other					(1)
Foreign currency translation adjustment						(193)
Change in unrealized gains (losses) on investments	(38)					(38)
Change in unrealized gains (losses) on derivative instruments						108
Tax benefit (provision) on above items						(13)
Ending balance at Jun. 30, 2018	$ 7,146	2	15,478	(23,892)	14,977	581
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends and dividend equivalents declared per share or restricted stock unit (in usd per share)	$ 0
Beginning balance at Mar. 31, 2018		2	15,362	(22,903)	14,335	800
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		0
Common stock repurchased/forfeited		0
Common stock and stock-based awards issued			58
Tax withholdings related to net share settlements of restricted stock units and awards			(93)
Stock-based compensation			151
Other			0
Common stock repurchased				(989)
Net income	$ 642				642
Dividends and dividend equivalents declared					0
Other					0
Foreign currency translation adjustment						(325)
Change in unrealized gains (losses) on investments	(2)					(2)
Change in unrealized gains (losses) on derivative instruments						137
Tax benefit (provision) on above items						(29)
Ending balance at Jun. 30, 2018	$ 7,146	2	15,478	(23,892)	14,977	581
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends and dividend equivalents declared per share or restricted stock unit (in usd per share)	$ 0
Beginning balance at Dec. 31, 2018	$ 6,281	2	15,716	(26,394)	16,459	498
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		0
Common stock repurchased/forfeited		0
Common stock and stock-based awards issued			55
Tax withholdings related to net share settlements of restricted stock units and awards			(119)
Stock-based compensation			260
Other			(1)
Common stock repurchased	(3,000)			(3,002)
Net income	920				920
Dividends and dividend equivalents declared					(254)
Other					0
Foreign currency translation adjustment						(52)
Change in unrealized gains (losses) on investments	56					56
Change in unrealized gains (losses) on derivative instruments						(30)
Tax benefit (provision) on above items						(8)
Ending balance at Jun. 30, 2019	$ 4,106	2	15,911	(29,396)	17,125	464
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends and dividend equivalents declared per share or restricted stock unit (in usd per share)	$ 0.28
Beginning balance at Mar. 31, 2019		2	15,785	(27,895)	16,847	464
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		0
Common stock repurchased/forfeited		0
Common stock and stock-based awards issued			52
Tax withholdings related to net share settlements of restricted stock units and awards			(65)
Stock-based compensation			139
Other			0
Common stock repurchased				(1,501)
Net income	$ 402				402
Dividends and dividend equivalents declared					(124)
Other					0
Foreign currency translation adjustment						(20)
Change in unrealized gains (losses) on investments	16					16
Change in unrealized gains (losses) on derivative instruments						11
Tax benefit (provision) on above items						(7)
Ending balance at Jun. 30, 2019	$ 4,106	$ 2	$ 15,911	$ (29,396)	$ 17,125	$ 464
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends and dividend equivalents declared per share or restricted stock unit (in usd per share)	$ 0.14