DISCONTINUED OPERATION - Assets and Liabilities Held-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
ASSETS:
Total assets held-for-sale	$ 0	$ 6,267,200	$ 7,516,456
LIABILITIES:
Total liabilities held-for-sale	0	$ 5,887,685
Ambac Assurance Corporation | Discontinued Operations, Held-for-Sale or Disposed of by Sale
ASSETS:
Total investments	2,226,505
Cash and equivalents	8,322
Premiums receivable	217,096
Reinsurance recoverable on paid and unpaid losses	25,274
Deferred ceded premiums	79,074
Subrogation recoverable	113,962
Intangible assets	213,457
Other assets, net	49,396
Restricted cash	57,754
VIE assets (including restricted cash of $57,754)	3,904,259
Valuation allowance on assets held-for-sale	(570,145)
Total assets held-for-sale	6,267,200
LIABILITIES:
Unearned premiums	228,177
Loss and loss adjustment reserves	577,167
Ceded premiums payable	56,404
Long-term debt and accrued interest	1,046,658
Other liabilities, net	105,772
VIE liabilities	3,873,507
Total liabilities held-for-sale	$ 5,887,685