Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Assets:
Available-for-sale Securities	$ 1,966
Debt Securities, Trading and Available-for-Sale	59
Short-term Investments	507	$ 414
Other Investments	568	690
Investments, Total	2,593	2,955
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	61	23
Restricted Cash	14	5
Premiums Receivable, Net	269	323
Reinsurance Recoverables, Including Reinsurance Premium Paid	115	55
Deferred ceded premium	124	90
Subrogation recoverable	271	2,092
Derivative assets	27	76
Intangible assets	326	362
Goodwill	61	46
Other assets	84	68
Total assets	7,973	12,303
Liabilities:
Unearned premiums	372	395
Liability for Claims and Claims Adjustment Expense	805	1,570
Ceded premiums payable	39	33
Capitalized Contract Cost, Net	5	0
Long-term debt	639	2,230
Accrued interest payable	427	576
Derivative liabilities	38	95
Other liabilities	163	133
Total liabilities	$ 6,647	$ 11,187
Preferred Stock, Shares Outstanding	0	0
Preferred stock, shares authorized	20,000,000	20,000,000
Stockholders’ equity:
Preferred Stock, Value, Issued	$ 0	$ 0
Common Stock, Value, Issued	0	0
Additional paid-in capital	274	257
Accumulated other comprehensive income (loss)	(253)	58
Retained earnings	1,245	726
Treasury Stock, Value	(15)	(3)
Total Ambac Financial Group, Inc. stockholders’ equity	1,252	1,038
Nonredeemable noncontrolling interest	53	60
Total stockholders’ equity	$ 1,305	$ 1,098
Preferred stock, par value	$ 0.01
Common stock, shares issued	46,658,990	46,477,068
Common stock, shares authorized	130,000,000	130,000,000
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$ 20	$ 18
Total liabilities, redeemable noncontrolling interest and stockholders’ equity	7,973	12,303
AFG [Member]
Assets:
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	44	21
Xchange
Stockholders’ equity:
Redeemable Noncontrolling Interest, Equity, Carrying Amount		7
Variable Interest Entity [Member]
Assets:
Available-for-sale Securities	1,967	3,455
Restricted Cash	17	2
Loans, at fair value	1,829	2,718
Derivative and other assets	241	40
Derivative assets	239	38
Other assets	2	2
Total assets	4,054	6,216
Variable interest entity assets:
Loans, at fair value	1,829	2,718
Liabilities:
Long-term debt	3,107	4,216
Derivative liabilities	1,048	1,940
Other liabilities	5	0
Total liabilities	4,160	6,156
Stockholders’ equity:
Long-term Debt	2,788	4,056
Fixed Income Securities [Member]
Assets:
Available-for-sale Securities	1,395	1,730
Collateral Pledged [Member]
Assets:
Available-for-sale Securities	64	120
Short-term Investments	64	105
Collateral Pledged [Member] | Fixed Income Securities [Member]
Assets:
Available-for-sale Securities	$ 0	$ 15