Note 8 - Earnings Per Share - Schedule of Reconciliation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Net income	$ 1,673	$ 1,569	$ 3,314	$ 3,199
Weighted-average number of shares outstanding:
Basic (in shares)	609.4	608.7	609.3	609.6
Diluted (in shares)	610.3	609.5	610.3	610.5
Earnings per share - basic (in dollars per share)	$ 2.75	$ 2.58	$ 5.44	$ 5.25
Earnings per share - diluted (in dollars per share)	$ 2.74	$ 2.57	$ 5.43	$ 5.24
Stock options excluded as their inclusion would be anti-dilutive (in shares)	0.5	1.0	0.5	0.9
Share-Based Payment Arrangement, Option [Member]
Weighted-average number of shares outstanding:
Dilutive effect of share based payment awards (in shares)	0.4	0.3	0.5	0.4
Retention Awards [Member]
Weighted-average number of shares outstanding:
Dilutive effect of share based payment awards (in shares)	0.5	0.5	0.5	0.5

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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