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Shareholders' Equity - Shares Repurchased (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended | 10 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Nov. 05, 2025 | Sep. 30, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Nov. 05, 2025 | Dec. 31, 2024 | Aug. 06, 2025
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchases of common stock |  |  |  |  |  |  |  |  | $ 369 | $ 412 |  |  |
Common Shares Outstanding |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchased additional authorized amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 300
Shares repurchased (in shares) |  | 1,423,121 | 1,537,505 | 1,335,228 | 1,054,727 | 1,658,441 | 1,928,328 | 1,539,278 |  |  |  | 6,180,774 |
Repurchases of common stock |  | $ 118 | $ 131 | $ 120 | $ 90 | $ 131 | $ 152 | $ 129 |  |  |  | $ 502 |
Average price paid per share (in dollars per share) |  | $ 83.06 | $ 85.03 | $ 89.72 | $ 86.11 | $ 78.87 | $ 78.50 | $ 84.07 |  |  |  | $ 81.28 |
Common Shares Outstanding | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchased additional authorized amount | $ 100 |  |  |  |  |  |  |  |  |  | $ 100 |  |
Remaining capacity of shares repurchase program | $ 332 |  |  |  |  |  |  |  |  |  | $ 332 |  |
Shares repurchased (in shares) | 621,471 |  |  |  |  |  |  |  |  |  | 4,917,325 |  |
Repurchases of common stock | $ 51 |  |  |  |  |  |  |  |  |  | $ 420 |  |
Average price paid per share (in dollars per share) | $ 82.14 |  |  |  |  |  |  |  |  |  | $ 85.37 |  |

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