Consolidated Statement of Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Accumulated Deficit	AOCI Attributable to Parent [Member]	Common Stock Held in Treasury	Total Stockholder's Equity	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2018		1,579				130
Balance at Dec. 31, 2018	$ 17,892	$ 158	$ 26,013	$ (12,041)	$ (605)	$ (3,727)	$ 9,798	$ 8,094
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards (in shares)	3					1
Exercised and issued stock-based awards	$ 1		1				1
Stock-based compensation, including the tender of shares	35		42			$ (8)	34	1
Contributions from noncontrolling interest	133		65				65	68
Adjustments to Additional Paid in Capital, Other	(22)		(22)				(22)
Dividends	(288)		(218)				(218)	(70)
Noncontrolling Interest, Period Increase (Decrease)	(12)		(1)				(1)	(11)
Net loss attributable to common stockholders	(248)			(248)			(248)
Net income (loss) attributable to noncontrolling interests	16							16
Other comprehensive income	35				35		35	0
Balance (in shares) at Sep. 30, 2019		1,582				131
Balance at Sep. 30, 2019	17,542	$ 158	25,880	(12,289)	(570)	$ (3,735)	9,444	8,098
Balance (in shares) at Jun. 30, 2019		1,582				131
Balance at Jun. 30, 2019	17,817	$ 158	25,949	(12,082)	(582)	$ (3,734)	9,709	8,108
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards (in shares)						0
Stock-based compensation, including the tender of shares	9		9			$ (1)	8	1
Contributions from noncontrolling interest	33		16				16	17
Adjustments to Additional Paid in Capital, Other	(22)		(22)				(22)
Dividends	(72)		(72)				(72)	0
Net loss attributable to common stockholders	(207)			(207)			(207)
Net income (loss) attributable to noncontrolling interests	(27)							(27)
Other comprehensive income	11				12		12	(1)
Balance (in shares) at Sep. 30, 2019		1,582				131
Balance at Sep. 30, 2019	17,542	$ 158	25,880	(12,289)	(570)	$ (3,735)	9,444	8,098
Balance (in shares) at Dec. 31, 2019		1,582				131
Balance at Dec. 31, 2019	$ 17,448	$ 158	25,830	(12,280)	(676)	$ (3,734)	9,298	8,150
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards (in shares)	2
Exercised and issued stock-based awards	$ 2		2				2
Stock-based compensation, including the tender of shares	42		46			$ (5)	41	1
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	1							1
Contributions from noncontrolling interest	115		56				56	59
Net loss attributable to common stockholders	(109)			(109)			(109)
Net income (loss) attributable to noncontrolling interests	116							116
Other comprehensive income	(53)				(52)		(52)	(1)
Balance (in shares) at Sep. 30, 2020		1,584				131
Balance at Sep. 30, 2020	17,562	$ 158	25,934	(12,389)	(728)	$ (3,739)	9,236	8,326
Balance (in shares) at Jun. 30, 2020		1,583				131
Balance at Jun. 30, 2020	$ 17,155	$ 158	25,905	(12,718)	(652)	$ (3,739)	8,954	8,201
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards (in shares)	1
Exercised and issued stock-based awards	$ 1		1				1
Stock-based compensation, including the tender of shares	8		8			$ 0	8	0
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	1							1
Contributions from noncontrolling interest	41		20				20	21
Net loss attributable to common stockholders	329			329			329
Net income (loss) attributable to noncontrolling interests	103							103
Other comprehensive income	(76)				(76)		(76)	0
Balance (in shares) at Sep. 30, 2020		1,584				131
Balance at Sep. 30, 2020	$ 17,562	$ 158	$ 25,934	$ (12,389)	$ (728)	$ (3,739)	$ 9,236	$ 8,326