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Shareholders' equity Share Repurchases (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 27, 2026	Mar. 31, 2026	Mar. 31, 2025	Jul. 01, 2025	Jul. 01, 2023
July 2023 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount					$ 5,000
Number of shares repurchased		3,517,810	1,345,782
Cost of shares repurchased			$ 385
Repurchase authorization remaining at end of period			$ 1,300
July 2025 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 5,000
Number of shares repurchased		3,517,810
Cost of shares repurchased		$ 1,143
Repurchase authorization remaining at end of period		$ 1,520
July 2025 Stock Repurchase Plan \| Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased	1,029,374
Cost of shares repurchased	$ 340
Repurchase authorization remaining at end of period	$ 1,182