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DISCONTINUED OPERATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 04, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2024 | Apr. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Common stock, par value (in dollars per share) |  |  |  |  |  | $ 0.01
Preferred stock, shares outstanding (in shares) |  | 0 | 0 |  |  |
Nonredeemable noncontrolling interest |  | $ 197,755 | $ 52,958 |  |  |
NOL allocated amount |  | $ 1,663,087 |  |  |  |
Dividend Rate on Auction Rate Preferred Shares |  | 11.448% |  |  |  |
Auction Market Preferred Shares | American Acorn Corporation |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Preferred stock, dividend rate, basis spread on reference rate |  |  |  | 200.00% |  |
Ambac Assurance Corporation | Discontinued Operations, Held-for-Sale or Disposed of by Sale |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Aggregate consideration | $ 420,000 |  |  |  |  |
Sale consummation extension period | 90 days |  |  |  |  |
Curable period for breach | 60 days |  |  |  |  |
Contingent termination fee payable | $ 22,000 |  |  |  |  |
Period from termination for alternative acquisition | 12 months |  |  |  |  |
Contingent reimbursement payable | $ 6,000 |  |  |  |  |
Number of securities called by warrants as percentage of fully diluted shares of common stock |  |  |  |  | 9.90% |
Warrants exercise price (in dollars per share) | $ 18.50 |  |  |  |  |
Warrants term | 6 years 6 months |  |  |  |  |
Purchase of co-investment, amount | $ 62,000 |  |  |  |  |
Purchase of co-investment, percent per annum | 7.50% |  |  |  |  |
Carrying amount of net assets held-for-sale |  | $ 962,637 |  |  |  |
Gain on purchase of AMPS |  | 0 | 0 | $ 1,131 |  |
Period for preferred stock auction occurrence | 28 days |  |  |  |  |
Loss on disposal |  | (570,145) | $ 0 | $ 0 |  |
Reclassification from AOCI at closing |  | (175,278) |  |  |  |
U. S. Federal Net Operating Tax | Interest Expense |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
NOL allocated amount |  | $ 110,494 |  |  |  |
Ambac Assurance Corporation |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Preferred stock, shares outstanding (in shares) |  | 4,596 | 4,596 |  |  |
Preferred stock, liquidation preference, value |  | $ 114,900 | $ 114,900 |  |  |
Nonredeemable noncontrolling interest |  | $ 50,918 |  |  |  |
5.1% Surplus Notes, General Account, Due 2020 | Ambac Assurance Corporation |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Debt instrument, interest rate |  | 5.10% |  |  |  |
Long-term debt, gross |  | $ 519,235 |  |  |  |
Long-term debt |  | $ 503,139 |  |  |  |
Secured Debt | Ambac UK |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Debt instrument, interest rate |  | 0.00% |  |  |  |
Long-term debt, gross |  | $ 40,600 |  |  |  |
Long-term debt |  | $ 18,079 |  |  |  |
Debt discount amortization rate |  | 7.40% |  |  |  |

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