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FINANCING - Equity Units (Details) - USD ($) shares in Millions, $ in Millions |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 01, 2022 | Aug. 31, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | May 31, 2022
Debt Instrument [Line Items] |  |  |  |  |  |
Proceeds from issuance of common stock |  |  | $ 36.0 | $ 1,808.0 | $ 73.0 |
Series 2019A Remarketable Junior Subordinated Notes | Junior subordinated notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Remarketed principal amount |  |  |  |  |  | $ 862.5
Quarterly interest rate |  |  |  |  |  | 4.475%
Series 2019B Remarketable Junior Subordinated Notes | Junior subordinated notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Remarketed principal amount |  |  |  |  |  | $ 862.5
Quarterly interest rate |  |  |  |  |  | 5.113%
2019 Series A Equity Units | Junior subordinated notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Common stock issued to settle purchase contracts (in shares) |  | 25.2 |  |  |  |
Proceeds from issuance of common stock | $ 1,725.0 |  |  |  |  |

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