Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]
Common Stock, Shares, Beginning period at Dec. 31, 2014		1,499
Beginning Balance at Dec. 31, 2014	$ 15,819	$ 2	$ 2,391	$ 301	$ 12,732	$ 393
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in noncontrolling interest	188					188
Net income (loss)	18,106				18,108	(2)
Other comprehensive loss, net of tax	(213)			(213)
Issuances under employee stock purchase plan, Shares		1
Issuances under employee stock purchase plan, Value	86		86
Issuance under equity incentive plans, Shares		21
Issuance under equity incentive plans, Value	235		235
Tax benefits from employee stock plans	586		586
Stock-based compensation	384		384
Repurchases of common stock, shares		(99)
Repurchases of common stock, value	(10,338)	$ (1)	(222)		(10,115)
Warrants settlement	(3,865)		(3,031)		(834)
Convertible notes settlement	(782)		(782)
Convertible note hedges settlement	784		784
Dividends declared	(1,890)				(1,890)
Reclassification to equity component of currently redeemable convertible notes	13		13
Common Stock, Shares, Ending period at Dec. 31, 2015		1,422
Ending Balance at Dec. 31, 2015	19,113	$ 1	444	88	18,001	579
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in noncontrolling interest	(90)					(90)
Net income (loss)	13,488				13,501	(13)
Other comprehensive loss, net of tax	190			190
Issuances under employee stock purchase plan, Shares		1
Issuances under employee stock purchase plan, Value	84		84
Issuance under equity incentive plans, Shares		13
Issuance under equity incentive plans, Value	128		128
Tax benefits from employee stock plans	186		186
Stock-based compensation	381		381
Repurchases of common stock, shares		(126)
Repurchases of common stock, value	(11,185)	$ 0	(302)		(10,883)
Warrants settlement	(469)		(469)
Convertible notes settlement	(95)		(95)
Convertible note hedges settlement	95		95
Dividends declared	(2,465)				(2,465)
Reclassification of conversion spread of convertible notes	(733)		(733)
Reclassification of convertible note hedges	733		733
Reclassification to equity component of currently redeemable convertible notes	$ 2		2
Common Stock, Shares, Ending period at Dec. 31, 2016	1,310	1,310
Ending Balance at Dec. 31, 2016	$ 19,363	$ 1	454	278	18,154	476
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in noncontrolling interest	(436)		(3)			(433)
Net income (loss)	4,644				4,628	16
Other comprehensive loss, net of tax	(113)			(113)
Issuances under employee stock purchase plan, Shares		1
Issuances under employee stock purchase plan, Value	83		83
Issuance under equity incentive plans, Shares		11
Issuance under equity incentive plans, Value	146		146
Stock-based compensation	618		618
Repurchases of common stock, shares		(14)
Repurchases of common stock, value	(1,062)		(34)		(1,028)
Dividends declared	$ (2,742)				(2,742)
Common Stock, Shares, Ending period at Dec. 31, 2017	1,308	1,308
Ending Balance at Dec. 31, 2017	$ 20,501	$ 1	$ 1,264	$ 165	$ 19,012	$ 59