v3.24.2.u1
Consolidated Balance Sheets - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2024
Jun. 30, 2024
Dec. 31, 2023
Dec. 31, 2022
Assets:        
Fixed maturity securities, at fair value $ 2,043,000 $ 2,043,000    
Total investments (net of allowance for credit losses of $3 and $3) 2,632,000 2,632,000 $ 2,664,000  
Restricted Cash 11,000 11,000 12,000  
Premiums Receivable, Net 317,000 317,000 290,000  
Premium Receivable, Allowance for Credit Loss 3,000 3,000 4,000  
Reinsurance Recoverables on Unpaid Losses, Allowance 0 0 0  
Reinsurance Recoverables, Including Reinsurance Premium Paid 277,000 277,000 195,000  
Deferred ceded premium 232,000 232,000 204,000  
Subrogation recoverable 128,000 128,000 137,000  
Derivative assets 18,000 18,000 26,000  
Intangible assets, less accumulated amortization 285,000 285,000 307,000  
Goodwill 70,000 70,000 70,000 $ 61,000
Other assets 163,000 163,000 129,000  
Total assets 8,184,000 8,184,000 8,428,000  
Liabilities:        
Unearned premiums 445,000 445,000 422,000  
Liability for Claims and Claims Adjustment Expense 890,000 890,000 893,000  
Ceded premiums payable 140,000 140,000 90,000  
Long-term debt 515,000 515,000 508,000  
Accrued interest payable 500,000 500,000 475,000  
Derivative Liability 26,000 26,000 35,000  
Other liabilities 203,000 203,000 199,000  
Total liabilities 6,748,000 6,748,000 6,997,000  
Redeemable Noncontrolling Interest, Equity, Redemption Value 17,000 17,000    
Redeemable Noncontrolling Interest, Equity, Carrying Amount 17,000 17,000 17,000 20,000
Liabilities 6,748,000 6,748,000 6,997,000  
Stockholders’ equity:        
Preferred stock, par value $0.01 per share; 20,000,000 shares authorized; issued and outstanding shares—none 0 0 0  
Common Stock, Value, Issued 0 0 0  
Additional paid-in capital 295,000 295,000 292,000  
Accumulated other comprehensive income (175,000) (175,000) (160,000) (253,000)
Retained earnings 1,265,000 1,265,000 1,246,000  
Treasury stock, shares at cost: 0 and 8,202 (17,000) (17,000) (17,000)  
Total Ambac Financial Group, Inc. stockholders’ equity 1,368,000 1,368,000 1,362,000  
Noncontrolling interest 51,000 51,000 53,000  
Total stockholders’ equity 1,419,000 1,419,000 1,415,000 1,305,000
Total liabilities and stockholders’ equity 8,184,000 8,184,000 8,428,000  
Debt Securities, Available-for-sale, Allowance for Credit Loss 3,000 3,000 3,000  
Debt Securities, Available-for-sale, Amortized Cost 2,078,000 2,078,000 2,197,000  
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents 97,000 97,000 274,000 $ 61,000
Deferred Policy Acquisition Cost 12,000 12,000 11,000  
Capitalized Contract Cost, Net $ 7,000 $ 7,000 $ 6,000  
Treasury Stock, Common, Shares 1,434,172 1,434,172 1,463,774  
Preferred Stock, Shares Issued 0 0 0  
Afg [Member]        
Stockholders’ equity:        
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents $ 35,000 $ 35,000 $ 28,000  
Short-term Investments [Member]        
Assets:        
Fixed maturity securities, at fair value 314,000 314,000 426,000  
Stockholders’ equity:        
Debt Securities, Available-for-sale, Allowance for Credit Loss 0 0 0  
Debt Securities, Available-for-sale, Amortized Cost 314,000 314,000 426,000  
Variable Interest Entity, Primary Beneficiary [Member]        
Assets:        
Fixed maturity securities, at fair value 2,101,000 2,101,000 2,167,000  
Restricted Cash 62,000 62,000 246,000  
Derivative assets 208,000 208,000 226,000  
Other assets 95,000 95,000 92,000  
Total assets 4,033,000 4,033,000 4,394,000  
Liabilities:        
Long-term debt 2,853,000 2,853,000 2,967,000  
Derivative Liability 1,136,000 1,136,000 1,197,000  
Other Sundry Liabilities, Current 59,000 59,000 240,000  
Other liabilities 7,000 7,000 5,000  
Total liabilities 4,048,000 4,048,000 4,404,000  
Liabilities 4,048,000 4,048,000 4,404,000  
Stockholders’ equity:        
Financing Receivable, after Allowance for Credit Loss 1,567,000 1,567,000 1,663,000  
Gross Investment Income, Operating 2,000      
Derivative and other assets 303,000 303,000 318,000  
Fixed Income Securities [Member]        
Assets:        
Fixed maturity securities, at fair value 1,703,000 1,703,000 1,710,000  
Stockholders’ equity:        
Debt Securities, Available-for-sale, Allowance for Credit Loss 3,000 3,000 3,000  
Debt Securities, Available-for-sale, Amortized Cost 1,737,000 1,737,000 1,744,000  
Debt Securities, Available-for-Sale, Excluding Accrued Interest 1,703,000 1,703,000 1,710,000  
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss 1,737,000 1,737,000 1,744,000  
Short-term Investments [Member]        
Assets:        
Fixed maturity securities, at fair value 314,000 314,000 426,000  
Stockholders’ equity:        
Gross Investment Income, Operating 5,000 10,000    
Other Investments [Member]        
Stockholders’ equity:        
Other Investment Not Readily Marketable, Fair Value 558,000 558,000 475,000  
Gross Investment Income, Operating 8,000 21,000    
Fixed Income Securities, Trading        
Stockholders’ equity:        
Gross Investment Income, Operating 2,000 4,000    
Debt Securities, Available-for-Sale, Excluding Accrued Interest 31,000 31,000 27,000  
Collateral Pledged [Member] | Fixed Income Securities [Member]        
Assets:        
Fixed maturity securities, at fair value 25,000 25,000 27,000  
Stockholders’ equity:        
Debt Securities, Available-for-sale, Amortized Cost 27,000 27,000 0  
Collateral Pledged [Member] | Fixed Income Securities [Member] | Short-term Investments [Member]        
Assets:        
Fixed maturity securities, at fair value 0 0 27,000  
Stockholders’ equity:        
Debt Securities, Available-for-sale, Allowance for Credit Loss 0 0 0  
Debt Securities, Available-for-sale, Amortized Cost 0 0 27,000  
Collateral Pledged [Member] | Short-term Investments        
Stockholders’ equity:        
Debt Securities, Available-for-sale, Amortized Cost 0 0 27,000  
Collateralized Securities | Fixed Income Securities [Member]        
Stockholders’ equity:        
Debt Securities, Available-for-Sale, Excluding Accrued Interest 25,000 25,000 0  
Collateralized Securities | Short-term Investments [Member]        
Assets:        
Fixed maturity securities, at fair value $ 0 $ 0 $ 27,000