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Stock Benefit Plans (Narrative) (Details) $ / shares in Units, $ in Millions |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
May 21, 2020 shares | May 01, 1999 purchase | May 31, 2018 shares | Mar. 31, 2018 shares | May 31, 2007 shares | Mar. 31, 2007 shares | Jul. 31, 2002 shares | Dec. 31, 2023 USD ($) $ / shares shares | Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Options, weighted-average grant-date fair value (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 41.92 | $ 31.38 | $ 22.25
Total intrinsic value of options exercised | $ |  |  |  |  |  |  |  | $ 164 | $ 56 | $ 138
Cash received from the exercise of stock options | $ |  |  |  |  |  |  |  | $ 116 | 50 | 103
Restricted Stock Units and Performance Stock Units |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Weighted-average period over which that cost is expected to be recognized, years |  |  |  |  |  |  |  | 1 year |  |
Vesting period, years | 3 years |  |  |  |  |  |  |  |  |
Total fair value of shares distributed in connection with non-option equity awards | $ |  |  |  |  |  |  |  | $ 398 | $ 560 | $ 278
Unrecognized compensation cost | $ |  |  |  |  |  |  |  | 368 |  |
Stock Options |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unrecognized compensation cost related to option awards | $ |  |  |  |  |  |  |  | $ 30 |  |
Weighted-average period over which that cost is expected to be recognized, years |  |  |  |  |  |  |  | 1 year 4 months 17 days |  |
Restricted Stock Units |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Weighted-average grant-date fair value (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 165.05 | $ 152.34 | $ 120.19
Performance Stock Units |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period, years | 3 years |  |  |  |  |  |  |  |  |
Performance-based restricted stock unit payable range minimum |  |  |  |  |  |  |  | 0.00% |  |
Performance-based restricted stock unit payable range maximum |  |  |  |  |  |  |  | 200.00% |  |
Performance period | 3 years |  |  |  |  |  |  |  |  |
Weighted-average grant-date fair value (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 170.80 | $ 151.00 | $ 122.77
Number of shares which became distributable during the period |  |  |  |  |  |  |  | 413,160 |  |
Performance Stock Units | PSUs Awarded in 2018 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period, years |  |  |  |  |  |  |  | 3 years |  |
Target payout percentage |  |  |  |  |  |  |  | 200.00% |  |
2020 Incentive and Stock Award Plan |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Awards authorized (in shares) | 20,000,000 |  |  |  |  |  |  |  |  |
2020 Incentive and Stock Award Plan | Restricted Stock Units and Performance Stock Units |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Awards authorized (in shares) | 12,500,000 |  |  |  |  |  |  |  |  |
2020 Incentive and Stock Award Plan | Stock Options |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Stock options vesting percentage | 25.00% |  |  |  |  |  |  |  |  |
Contractual term of stock option awards | 10 years |  |  |  |  |  |  |  |  |
1999 Plan | Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Awards authorized (in shares) |  |  |  |  |  |  |  | 40,350,000 |  |
Number of share purchase times per plan year | purchase |  | 4 |  |  |  |  |  |  |  |
Stock option price (as a percent) |  | 95.00% |  |  |  |  |  |  |  |
Reduction in the shares available (in shares) |  |  |  |  |  | 10,000,000 |  |  |  |
Shares due to shareholder action (in shares) |  |  | 4,750,000 |  |  |  |  |  |  |
Shares purchased by employees (in shares) |  |  |  |  |  |  |  | 331,017 |  |
Shares available for issuance under the plan (in shares) |  |  |  |  |  |  |  | 3,862,742 |  |
International Plan | Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Awards authorized (in shares) |  |  |  |  |  |  |  | 11,000,000 |  |
Reduction in the shares available (in shares) |  |  |  | 1,000,000 |  |  |  |  |  |
Shares due to shareholder action (in shares) |  |  |  |  | 4,000,000 |  | 5,000,000 |  |  |
Shares purchased by employees (in shares) |  |  |  |  |  |  |  | 116,578 |  |
Shares available for issuance under the plan (in shares) |  |  |  |  |  |  |  | 804,211 |  |

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