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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. 07, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Nov. 07, 2023 | Dec. 31, 2022 | Nov. 01, 2023
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchases of common stock |  |  |  |  |  |  |  |  | $ 90.0 | $ 400.0 |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  | 1,065,902 | 453,942 | 36,369 | 1,713,416 | 1,790,395 | 2,605,947 | 2,738,223 |  |  |  | 8,847,981 |
Repurchases of common stock |  | $ 64.0 | $ 24.0 | $ 2.0 | $ 100.0 | $ 97.0 | $ 151.0 | $ 155.0 |  |  |  | $ 503.0 |
Average price paid per share (in dollars per share) |  | $ 59.67 | $ 53.08 | $ 62.23 | $ 58.34 | $ 53.77 | $ 58.03 | $ 56.62 |  |  |  | $ 56.79 |
Common Shares | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchased additional authorized amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 300.0
Remaining capacity of shares repurchase program | $ 372.0 |  |  |  |  |  |  |  |  |  | $ 372.0 |  |
Shares repurchased (in shares) | 682,676 |  |  |  |  |  |  |  |  |  | 2,238,889 |  |
Repurchases of common stock | $ 42.0 |  |  |  |  |  |  |  |  |  | $ 132.0 |  |
Average price paid per share (in dollars per share) | $ 61.17 |  |  |  |  |  |  |  |  |  | $ 58.83 |  |

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