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INVESTMENTS IN UNCONSOLIDATED AFFILIATES - Narrative (Details) $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Feb. 12, 2024 USD ($) | Sep. 07, 2023 USD ($) a mile | Sep. 30, 2023 USD ($) turbine | Dec. 31, 2023 USD ($) project | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) project company | Dec. 31, 2022 USD ($) company | Dec. 31, 2021 USD ($) | Jan. 24, 2024
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Equity in (Losses)/Earnings of Subsidiaries |  |  |  |  |  | $ 15,500 | $ 22,900 | $ 14,200 |
Dividends received from equity method investees |  |  |  |  |  | $ 20,100 | 26,200 | 21,600 |
Number of offshore wind projects | project |  |  |  | 3 |  | 3 |  |  |
Payments to acquire investments |  |  |  |  |  | $ 1,680,473 | 742,496 | 327,385 |
Reduction of federal tax liability or generate tax refunds, period (in years) |  |  | 24 months |  |  |  |  |  |
Number of turbines | turbine |  |  | 12 |  |  |  |  |  |
Investment tax credit, percent realized |  |  |  |  | 0.10 |  |  |  |
Impairments of Offshore Wind Investments |  |  |  | $ 1,766,000 | $ 401,000 | 2,167,000 | $ 0 | $ 0 |
Equity method investment, other than temporary impairment, after tax |  |  |  | $ 1,622,000 | $ 331,000 | 1,953,000 |  |  |
Proceeds from sale, land, held-for-investment |  |  |  |  |  | $ 318,000 |  |  |
Number of companies that transmit hydro electricity imported from The Hydro-Quebec System in Canada | company |  |  |  |  |  | 2 | 2 |  |
Subsequent Event |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Investment tax credit, percent realized | 0.10 |  |  |  |  |  |  |  |
Expected investment tax credit | $ 170,000 |  |  |  |  |  |  |  |
Sunrise Wind LLC | Subsequent Event |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Negotiation period (in days) |  |  |  |  |  |  |  |  | 90 days
Offshore Wind Business - North East Offshore And Bay State Wind |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Carrying amount of equity method investments in excess of the underlying equity in net assets |  |  |  |  |  |  | $ 343,100 |  |
Basis difference |  |  |  |  |  |  | $ 168,900 |  |
Hydro-Quebec System |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  | 14.50% |  | 14.50% | 14.50% |  |
Payments to acquire investments |  |  |  |  |  | $ 9,600 | $ 9,300 |  |
South Fork Wind Holdings, LLC Class A |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  | 100.00% |  |  |  |  |  |
Impairments of Offshore Wind Investments |  |  |  | $ 4,000 |  |  |  |  |
Offshore Wind Business |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  | 50.00% |  | 50.00% |  |  |
Number of offshore wind projects | project |  |  |  | 2 |  | 2 |  |  |
Impairments of Offshore Wind Investments |  |  |  | $ 1,766,000 |  |  |  |  |
Uncommitted Lease Area |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  | 50.00% |  |  |  |  |  |  |
Land subject to ground leases | a |  | 175,000 |  |  |  |  |  |  |
Number of miles off south coast of Massachusetts | mile |  | 25 |  |  |  |  |  |  |
Payments to acquire investments |  | $ 625,000 |  |  |  |  |  |  |
Tax Equity Capital Contribution Agreement |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Payments to acquire investments |  |  | $ 528,000 |  |  |  |  |  |
Sunrise Wind LLC |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Impairments of Offshore Wind Investments |  |  |  | $ 1,218,000 |  |  |  |  |
Sunrise Wind LLC | Subsequent Event |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  |  |  |  |  |  | 50.00%
Sunrise Wind LLC | Orsted | Subsequent Event |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Equity method investment, percent of purchase price paid at closing (in percent) |  |  |  |  |  |  |  |  | 0.50
Equity method investment, percent of remaining purchase price paid (in percent) |  |  |  |  |  |  |  |  | 0.50
Renewable Energy Investment Fund |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  | 90.00% |  | 90.00% |  |  |
Proceeds from sale of equity method investments |  |  |  |  |  | $ 147,600 |  |  |
Renewable Energy Investment Fund | Equity Method Investee |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Payments for charitable contributions |  |  |  |  |  | $ 20,000 |  |  |
South Fork Wind, LLC |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  | 50.00% |  | 50.00% |  |  |
Northeast Offshore LLC and South Fork Class B Member, LLC |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) |  |  |  | 50.00% |  | 50.00% |  |  |
Number of offshore wind projects | project |  |  |  | 3 |  | 3 |  |  |
South Fork Wind And Revolution Wind | Subsequent Event |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Ownership interest (in percent) | 50.00% |  |  |  |  |  |  |  |
Proceeds from sale of equity method investments | $ 1,100,000 |  |  |  |  |  |  |  |
Cost sharing agreement, threshold amount | $ 240,000 |  |  |  |  |  |  |  |

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