Note 4 - Stock Options and Other Stock Plans - Additional Information Regarding Stock Option Exercises (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Intrinsic value of stock options exercised | $ 23 | $ 53 | $ 84 |
| Cash received from option exercises | 27 | 27 | 58 |
| Treasury shares repurchased for employee payroll taxes | (5) | (8) | (15) |
| Income tax benefit realized from option exercises | 5 | 8 | 16 |
| Aggregate grant-date fair value of stock options vested | $ 14 | $ 13 | $ 14 |