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Share Transactions - Share repurchases (Details) - Authorized Share Repurchase Program - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Nov. 05, 2025	Sep. 30, 2025	Sep. 30, 2024
Common shares
Class of Stock [Line Items]
Cumulative number of shares acquired since inception of share repurchase program		446,100,000
Aggregate purchase price of shares acquired since inception of share repurchase program		$ 7,000
Treasury stock, shares acquired (shares)		12,300,000	0
Aggregate cost of shares repurchased		$ 1,100
Remaining authorized repurchase amount		$ 1,900
Subsequent Event
Class of Stock [Line Items]
Treasury stock, shares acquired (shares)	4,700,000
Aggregate cost of shares repurchased	$ 411
Remaining authorized repurchase amount	$ 1,500

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