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Shareholders' Equity - Shares Repurchased (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 3 Months Ended | 6 Months Ended | 7 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Aug. 06, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Aug. 06, 2024 | Dec. 31, 2023 | May 02, 2024
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repurchases of common stock |  |  |  |  |  |  |  | $ 281 | $ 26 |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repurchased additional authorized amount |  |  |  |  |  |  |  |  |  |  |  | $ 300
Shares repurchased (in shares) |  | 1,928,328 | 1,539,278 | 1,659,680 | 1,065,902 | 453,942 | 36,369 |  |  |  | 3,215,893 |
Repurchases of common stock |  | $ 152 | $ 129 | $ 109 | $ 64 | $ 24 | $ 2 |  |  |  | $ 199 |
Average price paid per share (in dollars per share) |  | $ 78.50 | $ 84.07 | $ 65.83 | $ 59.67 | $ 53.08 | $ 62.23 |  |  |  | $ 61.95 |
Common Shares | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Remaining capacity of shares repurchase program | $ 275 |  |  |  |  |  |  |  |  | $ 275 |  |
Shares repurchased (in shares) | 599,497 |  |  |  |  |  |  |  |  | 4,067,103 |  |
Repurchases of common stock | $ 48 |  |  |  |  |  |  |  |  | $ 329 |  |
Average price paid per share (in dollars per share) | $ 79.96 |  |  |  |  |  |  |  |  | $ 80.82 |  |

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