Condensed Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Common Stock in Treasury	Additional Contributed Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Cumulative Effect, Period of Adoption, Adjustment	Parent	Parent Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling Interest
Adoption of new accounting standard	$ 7,866	$ 0	$ 683	$ (9,989)	$ 5,898	$ 15,075	$ 161	$ (3,823)	$ (161)	$ 7,844		$ 22
Beginning of period (in shares) at Dec. 31, 2018			683,000,000
Beginning of period at Dec. 31, 2018	7,866	0	$ 683	$ (9,989)	5,898	15,075	161	(3,823)	(161)	7,844		22
Beginning of period, treasury shares (in shares) at Dec. 31, 2018				170,000,000
Adoption of new accounting standard	7,866	0	$ 683	$ (9,989)	5,926	15,849	161	(4,288)	(161)	7,844		29
Net income	1,030					1,024				1,024		6
Other comprehensive income (loss)	$ (304)							(304)		(304)
Purchases of treasury stock (in shares)	(13,500,000)			14,000,000
Purchases of treasury stock	$ (1,043)			$ (1,089)	46					(1,043)
Stock issued under employee benefit plans and other (in shares)				(9,000,000)
Stock issued under employee benefit plans and other	394			$ 496	(18)	(84)				394
Dividends declared on common stock	(327)					(327)				(327)
Change in noncontrolling interests	1											1
End of period (in shares) at Sep. 30, 2019			683,000,000
End of period at Sep. 30, 2019	7,617		$ 683	$ (10,582)	5,926	15,849		(4,288)		7,588		29
End of period, treasury shares (in shares) at Sep. 30, 2019				175,000,000
Adoption of new accounting standard	7,803		$ 683	$ (10,322)	5,906	15,598		(4,086)		7,779		24
Beginning of period (in shares) at Jun. 30, 2019			683,000,000
Beginning of period at Jun. 30, 2019	7,803		$ 683	$ (10,322)	5,906	15,598		(4,086)		7,779		24
Beginning of period, treasury shares (in shares) at Jun. 30, 2019				173,000,000
Adoption of new accounting standard	7,617		$ 683	$ (10,582)	5,926	15,849		(4,288)		7,588		29
Net income	375					369				369		6
Other comprehensive income (loss)	(202)							(202)		(202)
Purchases of treasury stock (in shares)				4,000,000
Purchases of treasury stock	(346)			$ (346)	0					(346)
Stock issued under employee benefit plans and other (in shares)				(2,000,000)
Stock issued under employee benefit plans and other	105			$ 86	20	(1)				105
Dividends declared on common stock	(117)					(117)				(117)
Change in noncontrolling interests	(1)											(1)
End of period (in shares) at Sep. 30, 2019			683,000,000
End of period at Sep. 30, 2019	7,617		$ 683	$ (10,582)	5,926	15,849		(4,288)		7,588		29
End of period, treasury shares (in shares) at Sep. 30, 2019				175,000,000
Adoption of new accounting standard	7,617		683	$ (10,582)	5,926	15,849		(4,288)		7,588		29
Adoption of new accounting standard	$ 7,912	(4)	$ 683	(10,764)	5,955	15,718	(4)	(3,710)	0	7,882	$ (4)	30
Beginning of period (in shares) at Dec. 31, 2019	683,494,944		683,000,000
Beginning of period at Dec. 31, 2019	$ 7,912	(4)	$ 683	$ (10,764)	5,955	15,718	(4)	(3,710)	0	7,882	(4)	30
Beginning of period, treasury shares (in shares) at Dec. 31, 2019	177,340,358			177,000,000
Adoption of new accounting standard	$ 8,602	$ (4)	$ 683	$ (10,571)	5,955	15,718	$ (4)	(3,839)	$ 0	8,567	$ (4)	35
Net income	939					934				934		5
Other comprehensive income (loss)	(129)							(129)		(129)
Stock issued under employee benefit plans and other (in shares)				(4,000,000)
Stock issued under employee benefit plans and other	247			$ 193	54	0				247
Dividends declared on common stock	$ (363)					(363)				(363)
End of period (in shares) at Sep. 30, 2020	683,494,944		683,000,000
End of period at Sep. 30, 2020	$ 8,602		$ 683	$ (10,571)	6,009	16,285		(3,839)		8,567		35
End of period, treasury shares (in shares) at Sep. 30, 2020	172,705,772			173,000,000
Adoption of new accounting standard	$ 8,160		$ 683	$ (10,597)	5,975	16,055		(3,988)		8,128		32
Beginning of period (in shares) at Jun. 30, 2020			683,000,000
Beginning of period at Jun. 30, 2020	8,160		$ 683	$ (10,597)	5,975	16,055		(3,988)		8,128		32
Beginning of period, treasury shares (in shares) at Jun. 30, 2020				173,000,000
Adoption of new accounting standard	8,602		$ 683	$ (10,571)	6,009	16,285		(3,839)		8,567		35
Net income	359					356				356		3
Other comprehensive income (loss)	149							149		149
Stock issued under employee benefit plans and other (in shares)				0
Stock issued under employee benefit plans and other	60			$ 26	34					60
Dividends declared on common stock	$ (126)					(126)				(126)
End of period (in shares) at Sep. 30, 2020	683,494,944		683,000,000
End of period at Sep. 30, 2020	$ 8,602		$ 683	$ (10,571)	6,009	16,285		(3,839)		8,567		35
End of period, treasury shares (in shares) at Sep. 30, 2020	172,705,772			173,000,000
Adoption of new accounting standard	$ 8,602		$ 683	$ (10,571)	$ 6,009	$ 16,285		$ (3,839)		$ 8,567		$ 35