v3.26.1
Consolidated Balance Sheets - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Dec. 31, 2024
Assets:      
Debt Securities, Available-for-Sale $ 229,387 $ 268,737  
Total investments (net of allowance for credit losses of $0 and $0) 254,358 293,708  
Restricted Cash 46,634 40,754  
Premiums Receivable, Net 87,653 75,085  
Premium Receivable, Allowance for Credit Loss 500 500  
Reinsurance Recoverables, Including Reinsurance Premium Paid 469,859 436,092  
Deferred ceded premium 145,420 146,365  
Intangible assets, less accumulated amortization 458,380 474,998  
Goodwill 533,497 540,345 $ 418,234
Other Assets 101,673 92,003  
Total assets 2,267,026 2,223,317  
Liabilities:      
Unearned premiums 198,681 187,178  
Liability for Claims and Claims Adjustment Expense 487,261 459,990  
Ceded premiums payable 89,148 80,561  
Long-term debt 117,062 117,558  
Accrued interest payable 1,305 1,343  
Derivative Liability 426 8  
Other liabilities 158,458 102,771  
Total liabilities 1,237,483 1,137,151  
Redeemable Noncontrolling Interest, Equity, Carrying Amount 195,969 252,981 199,402
Liabilities 1,237,483 1,137,151  
Stockholders’ equity:      
Preferred stock, par value $0.01 per share; 20,000,000 shares authorized; issued and outstanding shares—none 0 0  
Common Stock, Value, Issued 489 489  
Additional paid-in capital 380,263 369,860  
Accumulated other comprehensive income 1,224 8,483 (188,436)
Retained earnings 363,751 370,431  
Treasury stock, shares at cost: 0 and 8,202 (33,109) (33,473)  
Total Ambac Financial Group, Inc. stockholders’ equity 712,618 715,790  
Noncontrolling interest 120,956 117,395  
Total stockholders’ equity 833,574 833,185 996,119
Total liabilities and stockholders’ equity 2,267,026 2,223,317  
Debt Securities, Available-for-sale, Allowance for Credit Loss 0 0  
Debt Securities, Available-for-sale, Amortized Cost 231,537 269,848  
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents 93,537 68,440 $ 47,275
Deferred Policy Acquisition Cost 16,451 9,732  
Capitalized Contract Cost, Net 6,929 6,978  
Deferred Income Tax Liabilities, Net $ 60,553 $ 65,217  
Treasury Stock, Common, Shares 3,863,290 3,871,598  
Preferred Stock, Shares Issued 0 0  
Short-Term Debt $ 0 $ 0  
Receivables, Net, Current 106,198 86,549  
Reinsurance Recoverable, Allowance for Credit Loss 100 100  
Accrued Liabilities for Commissions, Expense and Taxes 118,086 115,555  
Allowance for Credit Loss, Receivable, Other, Current 350 350  
Short-term Investments [Member]      
Assets:      
Debt Securities, Available-for-Sale 92,295 146,442  
Stockholders’ equity:      
Debt Securities, Available-for-sale, Allowance for Credit Loss 0 0  
Debt Securities, Available-for-sale, Amortized Cost 92,295 146,434  
Fixed Income Securities [Member]      
Assets:      
Debt Securities, Available-for-Sale 137,092 122,295  
Stockholders’ equity:      
Debt Securities, Available-for-sale, Allowance for Credit Loss 0 0  
Debt Securities, Available-for-sale, Amortized Cost 139,242 123,414  
Debt Securities, Available-for-Sale, Excluding Accrued Interest 137,092 122,295  
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss 139,242 123,414  
Short-term Investments [Member]      
Assets:      
Debt Securities, Available-for-Sale 92,295 146,442  
Stockholders’ equity:      
Gross Investment Income, Operating 1,244    
Other Investments [Member]      
Stockholders’ equity:      
Other Investment Not Readily Marketable, Fair Value 24,971 $ 24,971  
Gross Investment Income, Operating $ 0