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Shareholders' equity Repurchase of Common Shares (Details) - USD ($) $ in Millions	2 Months Ended	12 Months Ended
	Feb. 26, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jul. 01, 2025	Jul. 01, 2023	May 19, 2022
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased		11,986,574	7,518,565	11,825,600
2022 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased				11,825,600
Common Shares repurchased				$ 2,478
Stock repurchase program authorized amount							$ 2,500
July 2023 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased			7,518,565
Common Shares repurchased			$ 2,024
Stock repurchase program authorized amount						$ 5,000
July 2025 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased		11,986,574
Common Shares repurchased		$ 3,387
Stock repurchase program authorized amount					$ 5,000
Subsequent Event [Member] \| July 2025 Stock Repurchase Plan
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased	1,716,988
Common Shares repurchased	$ 551