Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance at Dec. 31, 2017		$ 0	$ 16	$ (1,717)	$ 17,161	$ (8,390)	$ (59)
Beginning Balance (Shares Issued) at Dec. 31, 2017		0	1,621,062,898
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 1,671					1,671
Cumulative Effect Of New Accounting Principles						(233)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment	(21)						(21)
Net change in derivative financial instruments	110						110
Defined benefit pensions and other items	2						2
Stock-based compensation					185
Stock-based compensation (Shares)			11,085,132
Ending Balance at Dec. 31, 2018		$ 0	$ 16	(1,717)	17,346	(6,953)	33
Ending Balance (Shares Issued) at Dec. 31, 2018		0	1,632,148,030
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	4,700					4,700
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment	195						195
Net change in derivative financial instruments	62						62
Defined benefit pensions and other items	(20)						(20)
Stock-based compensation					215
Stock-based compensation (Shares)			10,340,881
Ending Balance at Dec. 31, 2019	13,877	$ 0	$ 16	(1,717)	17,561	(2,253)	270
Ending Balance (Shares Issued) at Dec. 31, 2019		0	1,642,488,911
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(82)					(82)
Cumulative effect adjustment for adoption of ASC 2016-13	10					(10)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment	76						76
Net change in derivative financial instruments	(137)						(137)
Defined benefit pensions and other items	(1)						(1)
Stock Issuance (Par value)		$ 0	$ 0
Preferred stock issuance (Value in excess of par)					975
Common stock issuance (Value in excess of par)					975
Stock issuance (Shares)		10,062,500	29,382,500
Preferred stock dividends						(33)
Repurchase of common stock				(535)
Stock-based compensation					221
Stock-based compensation (Shares)			8,040,507
Ending Balance at Dec. 31, 2020	$ 15,326	$ 0	$ 17	$ (2,251)	$ 19,732	$ (2,378)	$ 207
Ending Balance (Shares Issued) at Dec. 31, 2020		10,062,500	1,679,911,918