Note 17 - Shareholders' Equity - Changes in Capital Stock (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance (in shares)	1,700
Balance	$ 863
Treasury stock (in shares)	(961)
Balance	$ 19,928
Shares issued to benefit plans and for option exercises	277	$ 323	$ 113
Shares purchased for treasury	(274)	(105)	(925)
Other, net (1)	$ (66)	$ (45)	$ (172)	[1]
Common stock, shares issued (in shares)	1,800	1,700
Treasury stock (in shares)	(970)	(961)
Balance (in shares)	1,800	1,700
Balance	$ 907	$ 863
Treasury stock (in shares)	(970)	(961)
Balance	$ 20,263	$ 19,928
Common Stock [Member]
Balance (in shares)	1,726	1,718	1,713
Balance	$ 863	$ 859	$ 857
Shares issued to benefit plans and for option exercises (in shares)	9	8	5
Shares issued to benefit plans and for option exercises	$ 4	$ 4	$ 2
Common stock, shares issued (in shares)	1,815	1,726	1,718
Conversion of preferred stock to common stock (in shares)	115
Conversion of preferred stock to common stock	$ 58
Repurchase of converted common stock (in shares)	(35)
Repurchase of converted common stock	$ (18)
Balance (in shares)	1,815	1,726	1,718
Balance	$ 907	$ 863	$ 859
Treasury Stock [Member]
Treasury stock (in shares)	(961)	(956)	(925)
Balance	$ 19,928	$ 19,812	$ 18,870
Shares purchased for treasury (in shares)	(7)	(4)	(31)
Shares purchased for treasury	$ (274)	$ (105)	$ (925)
Other, net (1)	$ (61)	$ (11)	$ (17)	[1]
Other, net (1) (in shares)	(2)	(1)
Treasury stock (in shares)	(970)	(961)	(956)
Treasury stock (in shares)	(970)	(961)	(956)
Balance	$ 20,263	$ 19,928	$ 19,812

[1] Adjustments to retained earnings include the effect of the accounting changes recorded for the adoption of the new standard for reclassification of stranded tax effects in accumulated other comprehensive loss in the amount of $53 million and the impact of an equity affiliate's adoption of the new revenue standard in January 2019. A net reduction of $186 million net of tax was recorded to beginning retained earnings for performance obligations of which a significant amount settled by the end of 2019.