Stock-based compensation - Schedule of financial information related to stock-based compensation (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per share of stock awards granted (in dollars per share)	$ 106.04	$ 104.27	$ 75.79
Intrinsic value of stock awards exercised	$ 298	$ 354	$ 356
Fair value of stock awards vested	46	56	53
Cash received from stock awards exercised	$ 82	$ 113	$ 98
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per share of stock awards granted (in dollars per share)	$ 357.02	$ 338.65	$ 252.24
Fair value of stock awards vested	$ 136	$ 144	$ 126
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per share of stock awards granted (in dollars per share)	$ 345.60	$ 408.64	$ 251.97
Fair value of stock awards vested	$ 127	$ 94	$ 80

Amount of cash inflow from exercise of option under share-based payment arrangement.

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