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Common Shareholders’ Equity and Noncontrolling Interests - Noncontrolling Interests (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | $ 647.3 | $ 321.1
Ark |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 410.4 | 336.9
HG Global |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | (13.4) | 0.8
Kudu |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 127.6 | 113.8
Bamboo |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 113.6 | 0.0
Other |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 9.1 | 9.4
Total, excluding BAM |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 647.3 | 460.9
BAM |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 0.0 | (139.8)
Ark - Management Equity Incentive |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | 42.9 | 21.0
Kudu - Management Equity Incentive |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Equity | $ 47.9 | $ 38.7
Ark |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Percentage | 27.90% | 28.00%
HG Global |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Percentage | 3.10% | 3.10%
Kudu |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Percentage | 9.60% | 10.50%
Bamboo |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Percentage | 27.20% | 0.00%
BAM |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Percentage | 100.00% | 100.00%

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