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Shareholders' Equity - Share repurchase program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	2 Months Ended	12 Months Ended
	Feb. 24, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Common shares held in treasury (shares)		240.8	219.2	218.5
Common shares held in treasury, at cost		$ 6,410.0	$ 4,487.0
Authorized Share Repurchase Program
Class of Stock [Line Items]
Aggregate cost of shares repurchased		$ 1,889.8	$ 23.5	$ 0.0
Number of shares repurchased (shares)		21.2	0.3	0.0
Average price per share repurchased		$ 89.26	$ 89.63	$ 0
Common shares | Authorized Share Repurchase Program
Class of Stock [Line Items]
Remaining share repurchase authorization		$ 1,100.0
Cumulative number of shares acquired since inception of share repurchase program		455.0
Aggregate purchase price of shares acquired since inception of share repurchase program		$ 7,800.0
Common shares | Authorized Share Repurchase Program | Subsequent Event
Class of Stock [Line Items]
Remaining share repurchase authorization	$ 702.0
Aggregate cost of shares repurchased	$ 405.0
Number of shares repurchased (shares)	4.3

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