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Earnings Per Share - Schedule of Basic and Diluted Earnings (Loss) Per Share (Details) - USD ($) shares in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Numerator |  |  |
Net income (controlling interest) | $ 511.6 | $ 672.9 | $ 1,145.9
Income from hypothetical settlement of Redeemable non-controlling interests, net of tax | 20.5 | 49.0 | 82.9
Interest expense on junior convertible securities, net of taxes | 13.4 | 13.4 | 14.0
Net income (controlling interest), as adjusted | $ 545.5 | $ 735.3 | $ 1,242.8
Denominator |  |  |
Average shares outstanding (basic) (in shares) | 31.1 | 35.1 | 38.5
Effect of dilutive instruments: |  |  |
Stock options and restricted stock units (in shares) | 1.7 | 1.7 | 1.3
Hypothetical issuance of shares to settle Redeemable non-controlling interests (in shares) | 1.6 | 3.7 | 7.4
Junior convertible securities (in shares) | 1.7 | 1.7 | 1.8
Average shares outstanding (diluted) (in shares) | 36.1 | 42.2 | 49.0

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