MBIA (MBI) 10-Q 9 May 24 2024 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2024	May 02, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000814585
Current Fiscal Year End Date	--12-31
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2024
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Trading Symbol	MBI
Entity Registrant Name	MBIA INC.
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		51,276,529
Title of 12(b) Security	Common Stock
Security Exchange Name	NYSE
Entity File Number	001-09583
Entity Tax Identification Number	06-1185706
Entity Address, Address Line One	1 Manhattanville Road, Suite 301
Entity Address, City or Town	Purchase
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10577
Entity Incorporation, State or Country Code	CT
City Area Code	914
Local Phone Number	273-4545

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments:
Assets held for sale	$ 74	$ 73
Total assets	2,488	2,606
Liabilities:
Liabilities held for sale	64	64
Total liabilities	4,211	4,253
Commitments and contingencies (Refer to Note 12: Commitments and Contingencies)
Equity:
Preferred stock, par value $1 per share; authorized shares—10,000,000; issued and outstanding—none	0	0
Common stock, par value $1 per share; authorized shares--400,000,000; issued shares--283,186,115 and 283,186,115	283	283
Additional paid-in capital	2,486	2,515
Retained earnings (deficit)	(1,230)	(1,144)
Accumulated other comprehensive income (loss), net of tax of $7 and $7	(131)	(139)
Treasury stock, at cost--231,910,363 and 232,323,184 shares	(3,141)	(3,172)
Total shareholders' equity of MBIA Inc.	(1,733)	(1,657)
Preferred stock of subsidiary and noncontrolling interest held for sale	10	10
Total equity	(1,723)	(1,647)
Total liabilities and equity	2,488	2,606
Non Variable Interest Entity [Member]
Investments:
Fixed-maturity securities held as available-for-sale, at fair value (amortized cost $1,186 and $1,175)	1,040	1,043
Investments carried at fair value	321	337
Short-term investments, at fair value (amortized cost $442 and $548)	442	548
Other investments at amortized cost	3	3
Total investments	1,806	1,931
Cash and cash equivalents	131	104
Premiums receivable (net of allowance for credit losses $- and $-)	145	146
Deferred acquisition costs	30	31
Insurance loss recoverable	179	183
Assets held for sale	74	73
Other assets	57	76
Liabilities:
Unearned premium revenue	224	232
Loss and loss adjustment expense reserves	470	473
Long-term debt	2,625	2,585
Medium-term notes (includes financial instruments carried at fair value of $36 and $40)	457	497
Investment agreements	220	221
Liabilities held for sale	64	64
Other liabilities	85	86
Variable Interest Entity, Primary Beneficiary [Member]
Investments:
Investments carried at fair value	22	22
Other assets	2	2
Cash	6	3
Loans receivable at fair value	36	35
Liabilities:
Variable interest entity debt (includes financial instruments carried at fair value of $46 and $78)	51	81
Derivative liabilities	$ 15	$ 14

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fixed-maturity securities held as available-for-sale, amortized cost	$ 1,544
Preferred stock, par value	$ 1	$ 1
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0
Common stock, par value	$ 1	$ 1
Common stock, authorized shares	400,000,000	400,000,000
Common stock, issued shares	283,186,115	283,186,115
Accumulated other comprehensive income (loss), taxes	$ 7	$ 7
Treasury stock, shares	231,910,363	232,323,184
Non Variable Interest Entity [Member]
Fixed-maturity securities held as available-for-sale, amortized cost	$ 1,186	$ 1,175
Short-term investments, amortized cost	442	548
Premiums receivable (net of allowance for credit losses)	0	0
Medium-term notes, financial instruments carried at fair value	36	40
Variable Interest Entity, Primary Beneficiary [Member]
Variable interest entity debt (includes financial instruments carried at fair value)	$ 46	$ 78

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Revenues:
Net realized investment gains (losses)		$ (1)	$ (3)
Net gains (losses) on financial instruments at fair value and foreign exchange		4	(13)
Net gains (losses) on extinguishment of debt		1	0
Total revenues		13	2
Expenses:
Losses and loss adjustment		18	6
Interest		52	51
Total expenses		100	85
Income (loss) from continuing operations before income taxes		(87)	(83)
Provision (benefit) for income taxes		0	0
Income (loss) from continuing operations		(87)	(83)
Income (loss) from discontinued operations, net of income taxes		1	(3)
Net income (loss)		(86)	(86)
Less: Net income from discontinued operations attributable to noncontrolling interest		0	7
Net income (loss) attributable to MBIA Inc.		$ (86)	$ (93)
Net income (loss) per common share attributable to MBIA Inc. - basic and diluted
Continuing operations - basic		$ (1.88)	$ (1.67)
Continuing operations - diluted		(1.88)	(1.67)
Discontinued operations - basic		0.04	(0.19)
Discontinued operations - diluted		0.04	(0.19)
Net income (loss) per common share attributable to MBIA Inc. - basic		(1.84)	(1.86)
Net income (loss) per common share attributable to MBIA Inc. - diluted		$ (1.84)	$ (1.86)
Weighted average number of common shares outstanding:
Basic	[1]	46,820,922	49,945,917
Diluted	[1]	46,820,922	49,945,917
Non Variable Interest Entity [Member]
Revenues:
Total premiums earned (net of ceded premiums of $- and $-)		$ 9	$ 10
Net investment income		23	26
Net realized investment gains (losses)		(1)	(3)
Net gains (losses) on financial instruments at fair value and foreign exchange		4	(13)
Other net realized gains (losses)		2	0
Expenses:
Losses and loss adjustment		18	6
Amortization of deferred acquisition costs		1	2
Operating		25	22
Interest		52	51
Variable Interest Entity, Primary Beneficiary [Member]
Revenues:
Net gains (losses) on financial instruments at fair value and foreign exchange		(25)	(3)
Other net realized gains (losses)		0	(15)
Expenses:
Operating		$ 4	$ 4
[1] Includes approximately 1 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended March 31, 2024 and 2023 .

Consolidated Statements Of Op_2

Consolidated Statements Of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financial Guarantee Insurance Segment [Member]
Ceded premiums earned	$ 0	$ 0

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statements of Comprehensive Income (Loss)
Net income (loss) attributable to MBIA Inc.	$ (86)	$ (93)
Available-for-sale securities with no credit losses:
Unrealized gains (losses) arising during the period	(15)	43
Reclassification adjustments for (gains) losses included in net income (loss)	0	5
Foreign currency translation gains (losses)	0	(1)
Instrument-specific credit risk of liabilities measured at fair value:
Unrealized gains (losses) arising during the period	4	1
Reclassification adjustments for (gains) losses included in net income (loss)	19	14
Total other comprehensive income (loss)	8	62
Comprehensive income (loss) attributable to MBIA Inc.	$ (78)	$ (31)

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings (Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total Shareholders' Equity Of MBIA Inc. [Member]	Preferred Stock [Member]	Preferred Stock And Non Controlling Interest Held For Sale [Member]
Balance (in common stock shares)		283,186,115
Balance (in preferred stock shares)								1,315
Total equity balance at Dec. 31, 2022		$ 283	$ 2,925	$ (653)	$ (283)	$ (3,154)	$ (882)		$ 6
Balance (in treasury stock shares) at Dec. 31, 2022						(228,333,444)
Share-based compensation			(10)			$ 11
Net income (loss) attributable to MBIA Inc.	$ (93)			(93)
Other comprehensive income (loss)	62				62
Share-based compensation (in treasury stock shares)						111,803
Period change							(30)		7
Total equity balance at Mar. 31, 2023	$ (899)	$ 283	2,915	(746)	(221)	$ (3,143)	(912)		13
Balance (in treasury stock shares) at Mar. 31, 2023						(228,221,641)
Balance (in common stock shares)		283,186,115
Balance (in preferred stock shares)								1,315
Balance (in common stock shares)	283,186,115	283,186,115
Balance (in preferred stock shares)	0							1,315
Total equity balance at Dec. 31, 2023	$ (1,647)	$ 283	2,515	(1,144)	(139)	$ (3,172)	(1,657)		10
Balance (in treasury stock shares) at Dec. 31, 2023	(232,323,184)					(232,323,184)
Share-based compensation			(29)			$ 31
Net income (loss) attributable to MBIA Inc.	$ (86)			(86)
Other comprehensive income (loss)	8				8
Share-based compensation (in treasury stock shares)						412,821
Period change							(76)		0
Total equity balance at Mar. 31, 2024	$ (1,723)	$ 283	$ 2,486	$ (1,230)	$ (131)	$ (3,141)	$ (1,733)		$ 10
Balance (in treasury stock shares) at Mar. 31, 2024	(231,910,363)					(231,910,363)
Balance (in common stock shares)	283,186,115	283,186,115
Balance (in preferred stock shares)	0							1,315

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Premiums, fees and reimbursements received	$ 2	$ 2
Investment income received	16	26
Financial guarantee losses and loss adjustment expenses paid	(19)	(28)
Proceeds from recoveries and reinsurance, net of salvage paid to reinsurers	2	3
Operating expenses paid and other operating	(19)	(34)
Other proceeds from consolidated variable interest entities	0	15
Interest paid, net of interest converted to principal	(12)	(14)
Cash (used) provided by discontinued operations	0	(6)
Net cash provided (used) by operating activities	(30)	(36)
Cash flows from investing activities:
Purchases of available-for-sale investments	(53)	(247)
Sales of available-for-sale investments	28	98
Paydowns, maturities and other proceeds of available-for-sale investments	28	49
Purchases of investments at fair value	(46)	(24)
Sales, paydowns, maturities and other proceeds of investments at fair value	65	209
Sales, paydowns and maturities (purchases) of short-term investments, net	112	(13)
(Payments) proceeds for derivative settlements	(1)	(1)
Net cash provided (used) by investing activities	133	71
Cash flows from financing activities:
Proceeds from investment agreements	0	2
Principal paydowns of investment agreements	(1)	(1)
Principal paydowns of medium-term notes	(36)	0
Proceeds from variable interest entity debt	2	0
Principal paydowns/redemptions of variable interest entity debt	(36)	(21)
Purchases of treasury stock	(2)	(4)
Cash provided (used) by discontinued operations	0	4
Net cash provided (used) by financing activities	(73)	(20)
Net increase (decrease) in cash and cash equivalents	30	15
Cash and cash equivalents - beginning of year	108	78
Cash and cash equivalents - end of year	138	93
Reconciliation of net income (loss) to net cash provided (used) by operating activities:
Net income (loss)	(86)	(86)
Income (loss) from discontinued operations, net of income taxes	1	(3)
Income (loss) from continuing operations	(87)	(83)
Change in:
Unearned premium revenue	(8)	(9)
Loss and loss adjustment expense reserves	(3)	(66)
Insurance loss recoverable	4	42
Accrued interest payable	36	34
Other assets and liabilities	1	7
Net realized investment gains (losses)	1	3
Net (gains) losses on financial instruments at fair value and foreign exchange	21	16
Other net realized (gains) losses	(2)	15
Other operating	7	5
Total adjustments to income (loss) from continuing operations	57	47
Net cash provided (used) by operating activities	$ (30)	$ (36)

Business Developments and Risks

Business Developments and Risks and Uncertainties	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Business Developments and Risks and Uncertainties	Note 1: Business De velopments and Risks and Uncertainties Summary MBIA Inc., together with its consolidated subsidiaries, (collectively, “MBIA” or the “Company”) operates within the financial guarantee insurance industry. MBIA manages three operating segments: 1) United States (“U.S.”) public finance insurance; 2) corporate; and 3) international and structured finance insurance. The Company’s U.S. public finance insurance business is managed through National Public Finance Guarantee Corporation (“National”), the corporate segment is operated through MBIA Inc. and several of its subsidiaries, including its service company, MBIA Services Corporation (“MBIA Services”) and its international and structured finance insurance business is primarily operated through MBIA Insurance Corporation and its subsidiaries (“MBIA Corp.”). Refer to “Note 9: Business Segments” for further information about the Company’s operating segments. Business Developments PREPA On January 1, 2024, the Puerto Rico Electric Power Authority (“PREPA”) defaulted on scheduled debt service for National insured bonds and National paid gross claims in the aggregate of $ 16 million. As of March 31, 2024, National had $ 792 million of insured debt service outstanding related to PREPA. On January 31, 2023, National entered into a restructuring support agreement (“PREPA RSA”) with the Financial Oversight and Management Board for Puerto Rico (the “Oversight Board”), on behalf of itself and as the sole Title III representative of PREPA. An amended plan of adjustment for PREPA and related disclosure statement was filed on February 9, 2023. On June 26, 2023, the Court entered an order reducing bondholder allowed net unsecured claims to $ 2.4 billion from approximately $ 7.6 billion. On August 25, 2023, National entered into the First Amendment to the PREPA Plan Support Agreement (the “Amended PSA”) with the Oversight Board, on behalf of itself and as the sole Title III representative of PREPA. By order dated November 17, 2023, the Court approved the Disclosure Statement for the Third Amended Plan incorporating, among other things, the terms of the Amended PSA. On December 29, 2023, the Oversight Board filed the Corrected Fourth Amended Title III Plan (the "Amended Plan"). The Amended PSA provides that, upon effective date of the Amended Plan, National shall receive cash, together with certain fees and expense reimbursement payments, in an amount based in part on the ultimate participation, if any, of certain currently non-accepting holders of uninsured PREPA bonds. The Amended PSA also provides National with additional consideration in the form of two types of contingent values instruments, whose value cannot be assured. The Amended PSA remains subject to a number of conditions, including (but not limited to) the Title III Court’s confirmation and effectiveness of the Amended Plan, as it may be further amended with the Court’s approval. The confirmation hearing commenced on March 4, 2024 and concluded on March 18, 2024. The Court has not ruled currently on confirmation of the Amended Plan. There is no assurance the Amended Plan will ultimately be confirmed and become effective. In the event of a substantially different confirmed plan of adjustment from the Amended PSA, National’s PREPA loss reserves and recoveries could be materially adversely affected. Refer to “Note 5: Loss and Loss Adjustment Expense Reserves” for additional information of the Company’s PREPA reserves and recoveries. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 1: Business Developments and Risks and Uncertainties (continued) Zohar CDOs Payment of claims on MBIA Corp.’s policies insuring the Class A-1 and A-2 notes issued by Zohar collateralized debt obligation (“CDO”) 2003-1, Limited (“Zohar I”) and Zohar II 2005-1, Limited (“Zohar II”) (collectively, the “Zohar CDOs”), entitled MBIA Corp. to reimbursement of such amounts plus interest and expenses and/or to exercise certain rights and remedies to seek recovery of such amounts. MBIA Corp. has anticipated that it would receive substantial recoveries on the loans made to, and equity interests in, portfolio companies that, until late March of 2020, were purportedly controlled and managed by the sponsor and former collateral manager of the Zohar CDOs (collectively, the “Zohar Collateral”). Since March of 2018, MBIA Corp. had been pursuing those recoveries in a Delaware bankruptcy proceeding filed by the Zohar CDOs (“Zohar Funds Bankruptcy Cases”). Pursuant to a plan of liquidation that became effective in August of 2022, all remaining Zohar Collateral was distributed to MBIA Corp. either directly or in the form of interests in certain asset recovery entities. There still remains significant uncertainty with respect to the realizable value of the remaining loans and equity interests that formerly constituted the Zohar Collateral. Further, as the monetization of these assets unfolds, and new information concerning the financial condition of the portfolio companies is disclosed, the Company will continue to revise its expectations for recoveries. The interests in the asset recovery entities include various loans to and equity interest in portfolio companies. For those portfolio companies in which the Company does not have a majority of the voting interest, the Company recorded these assets as investments. For those portfolio companies in which the Company owns a majority of the voting interest, the Company consolidated the assets, liabilities, and financial results of these companies. In accordance with Accounting Standards Codification (“ASC”) 360-10, Property, Plant, and Equipment and ASC 205-20, Presentation of Financial Statements-Discontinued Operations, certain of these portfolio companies met the criteria to be classified as held for sale and discontinued operations. Refer to the following “Discontinued Operations” section below for further information about the Company’s discontinued operations. In addition, certain of the Zohar debtors’ litigation claims were transferred into a litigation trust that the Company consolidated as a variable interest entity (“VIE”). Discontinued Operations For those Zohar-related portfolio companies in which the Company acquired an interest and which have met the criteria for held for sale classification in accordance with ASC 360, the Company classified these entities as held for disposition. Accordingly, the Company classified the assets and liabilities of consolidated portfolio companies and the interests in certain nonconsolidated portfolio companies as held for sale. Furthermore, as these entities met the one-year probable sale criteria on the acquisition date, and the remaining held for sale criteria within a short period following the acquisition date, these entities were classified as discontinued operations in accordance with ASC 205. As of March 31, 2024 and December 31, 2023, the assets and liabilities of these entities are presented within “Assets held for sale” and “Liabilities held for sale” on the Company’s consolidated balance sheets. Additionally, the results of operations for these entities are classified as “Income from discontinued operations, net of income taxes” on the Company’s consolidated statements of operations for the three months ended March 31, 2024 and 2023. For the net assets of the Company's Zohar-related portfolio companies that are classified as held for sale beyond one year, the Company continues to actively market its net assets held for sale and has identified interested parties, including having attained various stages of a sales or liquidation process. In addition, the Company has continued to (i) take necessary actions to respond to changes in circumstances, including recording a loss on disposal group; (ii) actively market the net assets at prices that are deemed reasonable; and (iii) meet the criteria for held for sale classification. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 1: Business Developments and Risks and Uncertainties (continued) The following table summarizes the components of assets and liabilities held for sale: As of In millions March 31, 2024 December 31, 2023 Assets held for sale Cash $ 1 $ 1 Accounts receivable 16 17 Goodwill 90 90 Other assets 9 9 Loss on disposal group ( 42 ) ( 44 ) Total assets held for sale $ 74 $ 73 Liabilities held for sale Accounts payable $ 6 $ 7 Debt 40 39 Accrued expenses and other 18 18 Total liabilities held for sale $ 64 $ 64 The results of operations from discontinued operations for the three months ended March 31, 2024 and 2023 consist of the following: Three Months Ended March 31, In millions 2024 2023 Revenues: Revenues $ 24 $ 32 Cost of sales 11 17 Total revenues from discontinued operations 13 15 Expenses: Operating 13 20 Interest 1 1 Increase (decrease) on loss on disposal group ( 2 ) ( 3 ) Total expenses from discontinued operations 12 18 Income (loss) before income taxes from discontinued operations 1 ( 3 ) Provision (benefit) for income taxes from discontinued operations - - Income (loss) from discontinued operations, net of income taxes $ 1 $ ( 3 ) Risks and Uncertainties The Company’s financial statements include estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses. The outcome of certain significant risks and uncertainties could cause the Company to revise its estimates and assumptions or could cause actual results to differ materially from the Company’s estimates. The discussion below highlights the significant risks and uncertainties that could have a material effect on the Company’s financial statements and business objectives in future periods. National’s Insured Portfolio National continues to monitor and remediate its existing insured portfolio. Certain state and local governments and territory obligors that National insures are under financial and budgetary stress. This could lead to an increase in defaults by such entities on the payment of their obligations and losses or impairments on a greater number of National’s insured transactions. In particular, PREPA is currently in bankruptcy-like proceedings in the United States District Court for the District of Puerto Rico. While National has entered into an agreement to support a plan to resolve the PREPA proceeding, PREPA may continue to fail to make payments when due, which could cause National to make additional claims payments which could be material. There is no assurance the PREPA amended plan of adjustment will ultimately be confirmed and go effective. National monitors and analyzes these situations and other stressed credits closely, and the overall extent and duration of this stress is uncertain. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 1: Business Developments and Risks and Uncertainties (continued) MBIA Corp.’s Insured Portfolio MBIA Corp.’s primary objectives are to satisfy all claims by its policyholders and to maximize future recoveries, if any, for its surplus note holders, and then its preferred stock holders. MBIA Corp. is executing this strategy by, among other things, taking steps to maximize the collection of recoveries and by reducing and mitigating potential losses on its insurance exposures. MBIA Corp.’s insured portfolio performance could deteriorate and result in additional significant loss reserves and claim payments. MBIA Corp.’s ability to meet its obligations is limited by available liquidity and its ability to secure additional liquidity through financing and other transactions. There can be no assurance that MBIA Corp. will be successful in generating sufficient resources to meet its obligations. Recoveries In addition to the recoveries on the Zohar Collateral, MBIA Corp. also projects to collect recoveries from prior claims associated with insured residential mortgage-backed securities (“RMBS”); however, the amount and timing of these collections are uncertain. Failure to collect its expected recoveries could impede MBIA Corp.’s ability to make payments when due on other policies. MBIA Corp. believes that if the New York State Department of Financial Services (“NYSDFS”) concludes at any time that MBIA Insurance Corporation will not be able to pay its policyholder claims, the NYSDFS would likely put MBIA Insurance Corporation into a rehabilitation or liquidation proceeding under Article 74 of the New York Insurance Law (“NYIL”) and/or take such other actions as the NYSDFS may deem necessary to protect the interests of MBIA Insurance Corporation’s policyholders. The determination to commence such a proceeding or take other such actions is within the exclusive control of the NYSDFS. Given the separation of MBIA Inc. and MBIA Corp. as distinct legal entities, the absence of any cross defaults between the entities and the lack of reliance by MBIA Inc. on MBIA Corp. for dividends, the Company does not believe that a rehabilitation or liquidation proceeding with respect to MBIA Insurance Corporation would have any significant liquidity impact on MBIA Inc. Such a proceeding could have material adverse consequences for MBIA Corp., including the termination of derivative contracts for which counterparties may assert market-based claims, the acceleration of debt obligations issued by affiliates and insured by MBIA Corp., the loss of control of MBIA Insurance Corporation to a rehabilitator or liquidator, and unplanned costs. Refer to “Note 5: Loss and Loss Adjustment Expense Reserves ” for additional information about MBIA Corp.’s recoveries.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Significant Accounting Policies	Note 2: Signif icant Accounting Policies The Company has disclosed its significant accounting policies in “Note 2: Significant Accounting Policies” in the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. The following significant accounting policies provide an update to those included in the Company’s Annual Report on Form 10-K. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 2: Significant Accounting Policies (continued) Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X and, accordingly, do not include all of the information and disclosures required by accounting principles generally accepted in the United States of America (“GAAP”) for annual periods. These statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Annual Report on Form 10-K for the year ended December 31, 2023. The accompanying consolidated financial statements have not been audited by an independent registered public accounting firm in accordance with the standards of the Public Company Accounting Oversight Board (U.S.), but in the opinion of management such financial statements include all adjustments, consisting only of normal recurring adjustments, necessary for the fair statement of the Company’s consolidated financial position and results of operations. All material intercompany balances and transactions have been eliminated. Certain amounts have been reclassified in prior years' financial statements to conform to the current presentation. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. As additional information becomes available or actual amounts become determinable, the recorded estimates are revised and reflected in operating results. The results of operations for the three months ended March 31, 2024 may not be indicative of the results that may be expected for the year ending December 31, 2024. The December 31, 2023 consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP for annual periods.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Recent Accounting Pronouncements	Note 3: Recen t Accounting Pronouncements Recently Adopted Accounting Standards The Company has not adopted any new accounting pronouncements that had a material impact on its consolidated financial statements. Recent Accounting Developments Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (ASU 2023-07) In November of 2023, the FASB issued ASU 2023-07, “Improvements to Reportable Segment Disclosures” which improves reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. In addition, the amendments enhance interim disclosure requirements, clarify circumstances in which an entity can disclose multiple segment measures of profit or loss, provide new segment disclosure requirements for entities with a single reportable segment, and contain other disclosure requirements. This ASU is effective for annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. Upon the effective date, the amendments should be applied retrospectively to all periods presented. The Company plans to adopt the amendments of ASU 2023-07 for fiscal year ending December 31, 2024 and is currently evaluating the potential impact of adopting ASU 2023-07. Income Taxes (Topic 740): Improvements to Income Tax Disclosure (ASU 2023-09) In December of 2023, the FASB issued ASU 2023-09, “Improvements to Income Tax Disclosures” which requires disaggregated information about a reporting entity’s effective tax rate reconciliation, information on income taxes paid, and contain other disclosure requirements. This ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted. Upon the effective date, the amendments should be applied prospectively with retrospective application permitted. The Company is currently evaluating the potential impact of adopting ASU 2023-09.

Variable Interest Entities

Variable Interest Entities	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Variable Interest Entities	Note 4: Va riable Interest Entities Primarily through MBIA’s international and structured finance insurance segment, the Company provides credit protection to issuers of obligations that may involve issuer-sponsored special purpose entities (“SPEs”). An SPE may be considered a variable interest entity (“VIE”) to the extent the SPE’s total equity at risk is not sufficient to permit the SPE to finance its activities without additional subordinated financial support or its equity investors lack any one of the following characteristics: (i) the power to direct the activities of the SPE that most significantly impact the entity’s economic performance or (ii) the obligation to absorb the expected losses of the entity or the right to receive the expected residual returns of the entity. A holder of a variable interest or interests in a VIE is required to assess whether it has a controlling financial interest, and thus is required to consolidate the entity as primary beneficiary. An assessment of a controlling financial interest identifies the primary beneficiary as the variable interest holder that has both of the following characteristics: (i) the power to direct the activities of the VIE that most significantly impact the entity’s economic performance and (ii) the obligation to absorb losses of the entity or the right to receive benefits from the entity that could potentially be significant to the VIE. The primary beneficiary is required to consolidate the VIE. An ongoing reassessment of controlling financial interest is required to be performed based on any substantive changes in facts and circumstances involving the VIE and its variable interests. The Company evaluates issuer-sponsored SPEs initially to determine if an entity is a VIE, and is required to reconsider its initial determination if certain events occur. For all entities determined to be VIEs, MBIA performs an ongoing reassessment to determine whether its guarantee to provide credit protection on obligations issued by VIEs provides the Company with a controlling financial interest. Based on its ongoing reassessment of controlling financial interest, the Company determines whether a VIE is required to be consolidated or deconsolidated. The Company makes its determination for consolidation based on a qualitative assessment of the purpose and design of a VIE, the terms and characteristics of variable interests of an entity, and the risks a VIE is designed to create and pass through to holders of variable interests. The Company generally provides credit protection on obligations issued by VIEs, and holds certain contractual rights according to the purpose and design of a VIE. The Company may have the ability to direct certain activities of a VIE depending on facts and circumstances, including the occurrence of certain contingent events, and these activities may be considered the activities that most significantly impact the VIE’s economic performance. The Company generally considers its guarantee of principal and interest payments of insured obligations, given nonperformance by a VIE, to be an obligation to absorb losses of the entity that could potentially be significant to the VIE. At the time the Company determines it has the ability to direct the activities of a VIE that most significantly impact the economic performance of the entity based on facts and circumstances, MBIA is deemed to have a controlling financial interest in the VIE and is required to consolidate the entity as primary beneficiary. The Company performs an ongoing reassessment of controlling financial interest that may result in consolidation or deconsolidation of any VIE. Consolidated VIEs The carrying amounts of assets and liabilities are presented separately in “Assets of consolidated variable interest entities” and “Liabilities of consolidated variable interest entities” on the Company’s consolidated balance sheets. VIEs are consolidated or deconsolidated based on an ongoing reassessment of controlling financial interest, when events occur or circumstances arise, and whether the ability to exercise rights that constitute power to direct activities of any VIE are present according to the design and characteristics of these entities. During the first quarter of 2024, there were no consolidations or deconsolidations of VIEs by the Company. During the first quarter of 2023, the Company deconsolidated one structured finance VIE due to the prepayment of the outstanding notes of the VIE and recorded losses of $ 15 million primarily due to credit losses in accumulated other comprehensive income ("AOCI") that were released to earnings. For the three months ended March 31, 2023, no additional VIEs were consolidated. Consolidation and deconsolidation gains and losses, if any, are recorded within “Other net realized gains (losses)” under “Revenues of consolidated variable interest entities” on the Company’s consolidated statements of operations. Holders of insured obligations of issuer-sponsored VIEs do not have recourse to the general assets of the Company. In the event of nonpayment of an insured obligation issued by a consolidated VIE, the Company is obligated to pay principal and interest, when due, on the respective insured obligation only. The Company’s exposure to consolidated VIEs is limited to the credit protection provided on insured obligations and any additional variable interests held by the Company. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 4: Variable Interest Entities (continued) Nonconsolidated VIEs The following tables present the Company’s maximum exposure to loss for nonconsolidated VIEs and carrying values of the assets and liabilities for its interests in these VIEs in its insurance operations as of March 31, 2024 and December 31, 2023. The maximum exposure to loss as a result of MBIA’s variable interests in VIEs is represented by insurance in force. Insurance in force is the maximum future payments of principal and interest which may be required under commitments to make payments on insured obligations issued by nonconsolidated VIEs. The Company has aggregated nonconsolidated VIEs based on the underlying credit exposure of the insured obligation. The nature of the Company’s variable interests in nonconsolidated VIEs is related to financial guarantees and any investments in obligations issued by nonconsolidated VIEs. March 31, 2024 Carrying Value of Assets Carrying Value of Liabilities In millions Maximum Exposure to Loss Investments Premiums Receivable Insurance Loss Recoverable Unearned Premium Revenue Loss and Loss Adjustment Expense Reserves Insurance: Global structured finance: Mortgage-backed residential $ 838 $ 19 $ 5 $ 21 $ 3 $ 232 Consumer asset-backed 111 - - 1 - 3 Corporate asset-backed 391 - 2 7 3 - Total global structured finance 1,340 19 7 29 6 235 Global public finance 210 - 4 - 3 - Total insurance $ 1,550 $ 19 $ 11 $ 29 $ 9 $ 235 December 31, 2023 Carrying Value of Assets Carrying Value of Liabilities In millions Maximum Exposure to Loss Investments Premiums Receivable Insurance Loss Recoverable Unearned Premium Revenue Loss and Loss Adjustment Expense Reserves Insurance: Global structured finance: Mortgage-backed residential $ 853 $ 19 $ 5 $ 23 $ 3 $ 239 Consumer asset-backed 121 - - 1 - 3 Corporate asset-backed 402 - 2 7 3 - Total global structured finance 1,376 19 7 31 6 242 Global public finance 218 - 4 - 4 - Total insurance $ 1,594 $ 19 $ 11 $ 31 $ 10 $ 242

Loss and Loss Adjustment Expens

Loss and Loss Adjustment Expense Reserves	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Loss and Loss Adjustment Expense Reserves	Note 5: Loss an d Loss Adjustment Expense Reserves U.S. Public Finance Insurance U.S. public finance insured transactions consist of municipal bonds, including tax-exempt and taxable indebtedness of U.S. political subdivisions, as well as utilities, airports, health care institutions, higher educational facilities, housing authorities and other similar agencies and obligations issued by private entities that finance projects that serve a substantial public purpose. The Company estimates future losses by using probability-weighted cash flow scenarios that are customized to each insured transaction. Future loss estimates consider debt service due for each insured transaction, which includes par outstanding and interest due, as well as recoveries for such payments, if any. Gross par outstanding for capital appreciation bonds represents the par amount at the time of issuance of the insurance policy. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 5: Loss and Loss Adjustment Expense Reserves (continued) PREPA In formulating loss reserves and recoveries for PREPA, estimates in the Company’s probability-weighted scenarios include assumptions related to the nature, value, and timing of net cash flows considering the following: environmental, economic, and political developments on the island; litigation and ongoing discussions with creditors and obligors on the Title III proceedings; contractual debt service payments; any existing settlement agreements or proposals and deviations from these proposals; the remediation strategy for insured obligations that have defaulted or are expected to default; and values of other obligations of the issuer. Refer to “Note 1: Business Developments and Risks and Uncertainties” for further information on the Company’s PREPA exposure. International and Structured Finance Insurance The international and structured finance insurance segment’s case basis reserves and insurance loss recoveries recorded in accordance with GAAP do not include reserves and recoveries on consolidated VIEs, since they are eliminated in consolidation. RMBS Case Basis Reserves (Financial Guarantees) The Company’s RMBS case basis reserves primarily relate to RMBS backed by alternative A-paper and subprime mortgage loans. The Company calculated RMBS case basis reserves as of March 31, 2024 using a process called the Roll Rate Methodology (“Roll Rate Methodology”). The Roll Rate Methodology is a multi-step process using databases of loan level information, proprietary internal cash flow models, and commercially available models to estimate potential losses and recoveries on insured bonds. Roll Rate is defined as the probability that current loans become delinquent and subsequently default and loans in the delinquent pipeline are charged-off or liquidated. The loss reserve estimates are based on a probability-weighted average of potential scenarios of loan losses. Additional data used for both first and second-lien loans include historic averages of deal specific voluntary prepayment rates, forward projections of the secured overnight financing rate, and historic averages of deal-specific loss severities. Where applicable, the Company factors in termination scenarios when clean up calls are imminent. In calculating ultimate cumulative losses for RMBS, the Company estimates the amount of first-lien loans that are expected to be liquidated in the future through foreclosure or short sale, and estimates, the amount of second-lien loans that are expected to be charged-off (deemed uncollectible by servicers of the transactions). The time to liquidation for a defaulted loan is specific to the loan’s delinquency bucket. For all RMBS transactions, cash flow models consider allocations and other structural aspects and claims against MBIA Corp.’s insurance policy consistent with such policy’s terms and conditions. The estimated net claims from the procedure above are then discounted using a risk-free rate to a net present value reflecting MBIA’s general obligation to pay claims over time and not on an accelerated basis. The Company monitors RMBS portfolio performance on a monthly basis against projected performance, reviewing delinquencies, roll rates, and prepayment rates (including voluntary and involuntary). However, loan performance remains difficult to predict and losses may exceed expectations. In the event of a material deviation in actual performance from projected performance, the Company would increase or decrease the case basis reserves accordingly and re-evaluate its assumptions. RMBS Recoveries The Company’s RMBS recoveries relate to structural features within the trust structures that allow for the Company to be reimbursed for prior claims paid. These reimbursements for specific trusts include recoveries that are generated from the excess spread of the transactions. Excess spread within insured RMBS securitizations is the difference between interest inflows on mortgage loan collateral and interest outflows on the insured RMBS notes. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 5: Loss and Loss Adjustment Expense Reserves (continued) Summary of Loss and LAE Reserves and Recoveries The Company’s loss and LAE reserves and recoveries before consolidated VIE eliminations, along with amounts that were eliminated as a result of consolidating VIEs for the international and structured finance insurance segment, which are included in the Company’s consolidated balance sheets as of March 31, 2024 and December 31, 2023 are presented in the following table: As of March 31, 2024 As of December 31, 2023 In millions Balance Sheet Line Item Balance Sheet Line Item Insurance loss recoverable Loss and LAE reserves (1) Insurance loss recoverable Loss and LAE reserves (1) U.S. Public Finance Insurance $ 150 $ 234 $ 152 $ 230 International and Structured Finance Insurance: Before VIE eliminations 30 321 32 335 VIE eliminations ( 1 ) ( 85 ) ( 1 ) ( 92 ) Total international and structured finance insurance 29 236 31 243 Total $ 179 $ 470 $ 183 $ 473 (1) - Amounts are net of estimated recoveries of expected future claims. Changes in Loss and LAE Reserves Loss and LAE reserves represent the Company’s estimate of future claims and LAE payments, net of any future recoveries of such payments. The following table presents changes in the Company’s loss and LAE reserves for the three months ended March 31, 2024. Changes in loss and LAE reserves, with the exception of loss and LAE payments, are recorded in “Losses and loss adjustment” expenses in the Company’s consolidated statements of operations. As of March 31, 2024 and December 31, 2023, the weighted average risk-free rates used to discount the Company’s loss reserves (claim liability) were 4.33 % and 3.97 %, respectively. LAE reserves are generally expected to be settled within a one-year period and are not discounted. As of March 31, 2024 and December 31, 2023 , the Company’s gross loss and LAE reserves included $ 8 million related to LAE. In millions Changes in Loss and LAE Reserves for the Three Months Ended March 31, 2024 Gross Loss Gross Loss and LAE Accretion Changes in and LAE Reserves as of Loss of Claim Changes in Unearned Reserves as of December 31, and LAE Liability Discount Changes in Premium March 31, 2023 Payments Discount Rates Assumptions (1) Revenue 2024 $ 473 $ ( 19 ) $ 4 $ ( 11 ) $ 26 $ ( 3 ) $ 470 (1) - Includes changes in amount and timing of estimated payments and recoveries. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 5: Loss and Loss Adjustment Expense Reserves (continued) The decrease in the Company’s loss and LAE reserves was primarily due to payments as well as an increase in risk-free rates during 2024, which caused future liabilities, net of recoveries to decline primarily on our RMBS insured transactions, partially offset by an increase in reserves for PREPA due to extending the timing of the effective date of a settlement, establishing reserves on a U.S. Public Finance lease-backed transaction, an increase in the secured overnight financing rate ("SOFR"), which increased estimated interest expense on floating rate liabilities and accretion. Changes in Insurance Loss Recoverable Insurance loss recoverable represents the Company’s estimate of expected recoveries on paid claims and LAE. The Company recognizes potential recoveries on paid claims based on the probability-weighted net cash inflows present valued at applicable risk-free rates as of the measurement date. The following table presents changes in the Company’s insurance loss recoverable for the three months ended March 31, 2024. Changes in insurance loss recoverable with the exception of collections, are recorded in “Losses and loss adjustment” expenses in the Company’s consolidated statements of operations. Changes in Insurance Loss Recoverable for the Three Months Ended March 31, 2024 Gross Gross Recoverable Recoverable as of Accretion Changes in as of December 31, Collections of Discount Changes in March 31, In millions 2023 for Cases Recoveries Rates Assumptions 2024 Insurance loss recoverable $ 183 $ ( 2 ) $ 2 $ ( 1 ) $ ( 3 ) $ 179 The decrease in the Company’s insurance loss recoverable reflected in the preceding table was primarily due extending the timing of a PREPA settlement, which reduced expected recoveries due to discounting over a longer time frame. Loss and LAE Activity For the three months ended March 31, 2024, the incurred loss primarily relates to extending the timing of the effective date of a PREPA settlement, establishing reserves on a U.S. public finance lease-backed transaction, an increase in SOFR, which increased interest expense on floating rate liabilities on the Company's RMBS portfolio, and accretion. This incurred loss was partially offset by an increase in risk-free rates, which caused future reserves, net of recoveries, to decline, primarily on the Company’s insured RMBS portfolio. For the three months ended March 31, 2023, the loss and LAE incurred primarily related to a decrease in risk-free rates during 2023, which caused liabilities to increase on our first-lien RMBS portfolio. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 5: Loss and Loss Adjustment Expense Reserves (continued) Costs associated with remediating insured obligations assigned to the Company’s surveillance categories are recorded as LAE and are included in “Losses and loss adjustment” expenses on the Company’s consolidated statements of operations. For the three months ended March 31, 2024 and 2023 , gross LAE related to remediating insured obligations was $ 2 million. Surveillance Categories The following table provides information about the financial guarantees and related claim liability included in each of MBIA’s surveillance categories as of March 31, 2024: Surveillance Categories Caution Caution Caution List List List Classified $ in millions Low Medium High List Total Number of policies 30 - - 96 126 Number of issues (1) 11 - - 78 89 Remaining weighted average contract period (in years) 5.9 - - 6.4 6.2 Gross insured contractual payments outstanding: (2) Principal $ 795 $ - $ - $ 1,686 $ 2,481 Interest 1,396 - - 629 2,025 Total $ 2,191 $ - $ - $ 2,315 $ 4,506 Gross Claim Liability (3) $ - $ - $ - $ 852 $ 852 Less: Gross Potential Recoveries (4) - - - 467 467 Discount, net (5) - - - 91 91 Net claim liability (recoverable) $ - $ - $ - $ 294 $ 294 Unearned premium revenue $ 5 $ - $ - $ 10 $ 15 Reinsurance recoverable on paid and unpaid losses (6) $ 13 (1) - An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt. (2) - Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA. (3) - The gross claim liability with respect to Puerto Rico exposures are net of expected recoveries for policies in a net payable position. (4) - Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position. (5) - Represents discount related to Gross Claim Liability and Gross Potential Recoveries. (6) - Included in "Other assets" on the Company's consolidated balance sheets. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 5: Loss and Loss Adjustment Expense Reserves (continued) The following table provides information about the financial guarantees and related claim liability included in each of MBIA’s surveillance categories as of December 31, 2023: Surveillance Categories Caution Caution Caution List List List Classified $ in millions Low Medium High List Total Number of policies 35 - - 94 129 Number of issues (1) 13 - - 77 90 Remaining weighted average contract period (in years) 5.6 - - 7.1 6.3 Gross insured contractual payments outstanding: (2) Principal $ 1,336 $ - $ - $ 1,244 $ 2,580 Interest 1,614 - - 504 2,118 Total $ 2,950 $ - $ - $ 1,748 $ 4,698 Gross Claim Liability (3) $ - $ - $ - $ 651 $ 651 Less: Gross Potential Recoveries (4) - - - 235 235 Discount, net (5) - - - 125 125 Net claim liability (recoverable) $ - $ - $ - $ 291 $ 291 Unearned premium revenue $ 9 $ - $ - $ 7 $ 16 Reinsurance recoverable on paid and unpaid losses (6) $ 13 (1) - An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt. (2) - Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA. (3) - The gross claim liability with respect to Puerto Rico exposures are net of expected recoveries for policies in a net payable position. (4) - Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position. (5) - Represents discount related to Gross Claim Liability and Gross Potential Recoveries. (6) - Included in "Other assets" on the Company's consolidated balance sheets.

Fair Value Of Financial Instrum

Fair Value Of Financial Instruments	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Fair Value Of Financial Instruments	Note 6: Fair Value of Financial Instruments Fair Value Measurement Financial Assets and Liabilities Financial assets held by the Company primarily consist of investments in debt and equity securities and loans receivables at fair value. Financial liabilities issued by the Company primarily consist of debt issued for general corporate purposes within its corporate segment, medium-term notes ("MTNs"), investment agreements, and debt issued by consolidated VIEs. Valuation Techniques Valuation techniques for financial instruments measured at fair value are described below. Fixed-Maturity Securities Held as Available-For-Sale, Investments Carried at Fair Value and Short-term Investments These investments include available-for-sale ("AFS") investments in U.S. Treasury and government agencies, state and municipal bonds, foreign governments, corporate obligations, MBS, ABS, money market securities, equity investments and loans carried at fair value. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Substantially all of these investments are valued based on recently executed transaction prices or quoted market prices by independent third parties, including pricing services and brokers. When quoted market prices are not available, fair value is generally determined using quoted prices of similar investments or a valuation model based on observable and unobservable inputs. Inputs vary depending on the type of investment. Observable inputs include contractual cash flows, interest rate yield curves, credit default swap (“CDS”) spreads, prepayment and volatility scores, diversity scores, cross-currency basis index spreads, and credit spreads for structures similar to the financial instrument in terms of issuer, maturity and seniority. Unobservable inputs include cash flow projections, the value of any credit enhancement and for certain equity investments, EBITDA multiples, discount rates, weightings, hard asset values and type certificate values. Investments based on quoted market prices of identical investments in active markets are classified as Level 1 of the fair value hierarchy. Level 1 investments generally consist of U.S. Treasury and government agency, money market securities and equity investments. Quoted market prices of investments in less active markets, as well as investments which are valued based on other than quoted prices for which the inputs are observable, such as interest rate yield curves, are categorized in Level 2 of the fair value hierarchy. Investments that contain significant inputs that are not observable are categorized as Level 3. Cash and Cash Equivalents The carrying amounts of cash and cash equivalents approximate fair value due to the short-term nature and credit worthiness of these instruments and are categorized in Level 1 of the fair value hierarchy. Variable Interest Entity Loans Receivable at Fair Value Loans receivable at fair value are assets held by a consolidated VIE consisting of residential mortgage loans and are categorized in Level 3 of the fair value hierarchy. Fair values of residential mortgage loans are determined using quoted prices for similar securities, adjusted for the fair values of the financial guarantees provided by MBIA Corp. on the related MBS. The fair values of the financial guarantees consider expected claim payments, net of recoveries, under MBIA Corp.’s policies. Other Assets Other assets include receivables representing the right to receive reimbursement payments on claim payments expected to be made on certain insured VIE liabilities due to risk mitigating transactions with third parties executed to effectively defease, or, in-substance commute the Company’s exposure on its financial guarantee policies. The right to receive reimbursement payments is based on the value of the Company’s financial guarantee determined using a cash flow model. The fair value of the financial guarantee primarily contains unobservable inputs and is categorized in Level 3 of the fair value hierarchy. Medium-term Notes at Fair Value The Company has elected to measure certain MTNs at fair value on a recurring basis. The fair values of certain MTNs are based on quoted market prices provided by third-party sources, where available. When quoted market prices are not available, the Company applies a matrix pricing grid to determine fair value based on the quoted market prices received for similar instruments and considering the MTNs’ stated maturity and interest rate. Nonperformance risk is included in the quoted market prices and the matrix pricing grid. MTNs are categorized in Level 3 of the fair value hierarchy and do not include accrued interest. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Variable Interest Entity Debt The fair values of VIE debt are determined based on recently executed transaction prices or quoted prices where observable. When position-specific quoted prices are not observable, fair values are based on quoted prices of similar securities. Fair values based on quoted prices of similar securities may be adjusted for factors unique to the securities, including any credit enhancement. Observable inputs include interest rate yield curves, bond spreads of similar securities and MBIA Corp.’s CDS spreads. Unobservable inputs include the value of any credit enhancement. VIE debt are categorized in Level 3 of the fair value hierarchy based on the lowest level input that is significant to the fair value measurement in its entirety. Derivatives A VIE consolidated by the Company entered into a derivative instrument consisting of a cross currency swap that as of March 31, 2024 and December 31, 2023 had outstanding notional amounts of $ 39 million. The cross currency swap was entered into to manage the variability in cash flows resulting from fluctuations in foreign currency rates. The fair value of the VIE derivative was determined based on the valuation provided by an independent third party, which is included in “Liabilities of consolidated variable interest entities – Derivative liabilities” on the Company’s consolidated balance sheets. As the significant inputs are unobservable, the derivative contract is categorized in Level 3 of the fair value hierarchy. Significant Unobservable Inputs The following tables provide quantitative information regarding the significant unobservable inputs used by the Company for assets and liabilities measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023: Fair Value as of Range March 31, (Weighted In millions 2024 Valuation Techniques Unobservable Input Average) Assets: Equity Investments $ 102 Discounted cash flow EBITDA multiples (1) Discount rate (1) Weightings (1) Sum of the parts Hard asset values (1) Type certificate values (1) Weightings (1) Loans carried at fair value 6 Discounted cash flow Discount rate (1) Assets of consolidated VIEs: Loans receivable at fair value 36 Market prices of similar liabilities adjusted for financial guarantees provided to VIE obligations Impact of financial guarantee 25 % - 25 % ( 25 %) (2) Liabilities of consolidated VIEs: Variable interest entity notes 46 Market prices of VIE assets adjusted for financial guarantees provided or market prices of similar liabilities Impact of financial guarantee 69 % - 69 % ( 69 %) (2) (1) - Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. (2) - Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Fair Value as of Range December 31, (Weighted In millions 2023 Valuation Techniques Unobservable Input Average) Assets: Equity Investments $ 108 Discounted cash flow EBITDA multiples (1) Discount rate (1) Weightings (1) Sum of the parts Hard asset values (1) Type certificate values (1) Weightings (1) Assets of consolidated VIEs: Loans receivable at fair value 35 Market prices of similar liabilities or internal cash flow models adjusted for financial guarantees provided to VIE obligations Impact of financial guarantee 27 % - 27 % ( 27 %) (2) Liabilities of consolidated VIEs: Variable interest entity notes 78 Market prices of VIE assets adjusted for financial guarantees provided or market prices of similar liabilities Impact of financial guarantee 74 % - 74 % ( 74 %) (2) (1) - Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. (2) - Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value. Sensitivity of Significant Unobservable Inputs The significant unobservable inputs used in the fair value measurement of the Company’s equity investments at fair value are EBITDA multiples, the discount rate, hard asset values and type certificate values. The fair value of equity investments is determined by taking a weighted average of valuation scenarios. If there had been lower or higher EBITDA multiples, hard asset values or type certificate values, the value of equity investments would have been lower or higher, respectively. If there had been a lower or higher discount rate, the value of equity investments would have been higher or lower, respectively. The significant unobservable input used in the fair value measurement of the loans carried at fair value is the discount rate. The fair value of loans carried at fair value is determined by discounting cash flows. The discount rate includes the credit spread which primarily reflects the credit quality of the obligor. If there had been a lower or higher discount rate, the value of loans carried at fair value would have been higher or lower, respectively. The significant unobservable input used in the fair value measurement of the Company’s residential loans receivable at fair value of consolidated VIEs is the impact of the financial guarantee. The fair value of residential loans receivable is calculated by subtracting the value of the financial guarantee from the market value of similar instruments to that of the VIE liabilities. The value of a financial guarantee is estimated by the Company as the present value of expected cash payments, net of recoveries, under the policy. If there had been a lower expected cash flow on the underlying loans receivable of the VIE, the value of the financial guarantee provided by the Company under the insurance policy would have been higher. This would have resulted in a lower fair value of the residential loans receivable in relation to the obligations of the VIE. The significant unobservable input used in the fair value measurement of the Company’s VIE notes of consolidated VIEs is the impact of the financial guarantee. The fair value of VIE notes is calculated by adding the value of the financial guarantee to the market value of VIE assets. When the VIE note is backed by RMBS, the fair value of the VIE liability is calculated by applying the market value of similar instruments to that of the VIE liabilities. The value of a financial guarantee is estimated by the Company as the present value of expected cash payments under the policy. If the value of the guarantee provided by the Company to the obligations issued by the VIE had increased, the credit support would have added value to the liabilities of the VIE. This would have resulted in an increased fair value of the liabilities of the VIE. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Fair Value Measurements The following tables present the fair value of the Company’s assets (including short-term investments) and liabilities measured and reported at fair value on a recurring basis as of March 31, 2024 and December 31, 2023: Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Active Markets Other Significant for Identical Observable Unobservable Balance as of Assets Inputs Inputs March 31, In millions (Level 1) (Level 2) (Level 3) 2024 Assets: Fixed-maturity investments: U.S. Treasury and government agency $ 546 $ 7 $ - $ 553 State and municipal bonds - 119 - 119 Foreign governments - 13 - 13 Corporate obligations - 490 7 (1) 497 Mortgage-backed securities: Residential mortgage-backed agency - 140 - 140 Residential mortgage-backed non-agency - 34 - 34 Commercial mortgage-backed - 14 - 14 Asset-backed securities: Collateralized debt obligations - 132 - 132 Other asset-backed - 63 - 63 Total fixed-maturity investments 546 1,012 7 1,565 Money market securities 85 - - 85 Equity investments 43 8 102 153 Cash and cash equivalents 131 - - 131 Assets of consolidated VIEs: Mortgage-backed securities: Residential mortgage-backed non-agency - 10 - 10 Commercial mortgage-backed - 10 - 10 Asset-backed securities: Collateralized debt obligations - 1 - 1 Other asset-backed - 1 - 1 Cash 6 - - 6 Loans receivable at fair value: Residential loans receivable - - 36 36 Other assets - - 2 2 Total assets $ 811 $ 1,042 $ 147 $ 2,000 Liabilities: Medium-term notes $ - $ - $ 36 $ 36 Other liabilities: Insured credit derivatives - 1 - 1 Liabilities of consolidated VIEs: Variable interest entity notes - - 46 46 Currency derivatives - - 15 15 Total liabilities $ - $ 1 $ 97 $ 98 (1) - Includes loans carried at fair value of $ 6 million. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Active Markets Other Significant for Identical Observable Unobservable Balance as of Assets Inputs Inputs December 31, In millions (Level 1) (Level 2) (Level 3) 2023 Assets: Fixed-maturity investments: U.S. Treasury and government agency $ 705 $ 7 $ - $ 712 State and municipal bonds - 123 - 123 Foreign governments - 18 - 18 Corporate obligations - 496 1 497 Mortgage-backed securities: Residential mortgage-backed agency - 149 - 149 Residential mortgage-backed non-agency - 34 - 34 Commercial mortgage-backed - 14 - 14 Asset-backed securities: Collateralized debt obligations - 146 - 146 Other asset-backed - 46 - 46 Total fixed-maturity investments 705 1,033 1 1,739 Money market securities 34 - - 34 Equity investments 39 8 108 155 Cash and cash equivalents 104 - - 104 Assets of consolidated VIEs: Mortgage-backed securities: Residential mortgage-backed non-agency - 10 - 10 Commercial mortgage-backed - 10 - 10 Asset-backed securities: Collateralized debt obligations - 1 - 1 Other asset-backed - 1 - 1 Cash 3 - - 3 Loans receivable at fair value: Residential loans receivable - - 35 35 Other assets - - 2 2 Total assets $ 885 $ 1,063 $ 146 $ 2,094 Liabilities: Medium-term notes $ - $ - $ 40 $ 40 Other liabilities: Insured credit derivatives - 1 - 1 Non-insured interest rate derivatives - 1 - 1 Liabilities of consolidated VIEs: Variable interest entity notes - - 78 78 Currency derivatives - - 14 14 Total liabilities $ - $ 2 $ 132 $ 134 Level 3 assets at fair value as of March 31, 2024 and December 31, 2023 represented approximately 7 % of total assets measured at fair value. Level 3 liabilities at fair value as of March 31, 2024 and December 31, 2023 represented approximately 99 % of total liabilities measured at fair value. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) The following tables present the fair values and carrying values of the Company’s assets and liabilities that are disclosed at fair value but not reported at fair value on the Company’s consolidated balance sheets as of March 31, 2024 and December 31, 2023 . The majority of the financial assets and liabilities that the Company requires fair value reporting or disclosures are valued based on the Company’s or a third-party’s estimate of discounted cash flow model estimates, or quoted market values for identical or similar products. Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Significant Fair Value Carry Value Active Markets for Other Observable Unobservable Balance as of Balance as of Identical Assets Inputs Inputs March 31, March 31, In millions (Level 1) (Level 2) (Level 3) 2024 2024 Assets: Other investments $ - $ - $ 3 $ 3 $ 3 Total assets $ - $ - $ 3 $ 3 $ 3 Liabilities: Long-term debt $ - $ 302 $ - $ 302 $ 2,625 Medium-term notes - - 235 235 418 (1) Investment agreements - - 236 236 220 Liabilities of consolidated VIEs: Variable interest entity loans payable - - 5 5 5 Total liabilities $ - $ 302 $ 476 $ 778 $ 3,268 Financial Guarantees: Gross liability (recoverable) $ - $ - $ 793 $ 793 $ 515 Ceded recoverable (liability) - - 20 20 16 (1) - The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of March 31, 2024, the Company had an immaterial amount of embedded derivative assets and had embedded derivative liabilities of $ 2 million. Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Significant Fair Value Carry Value Active Markets for Other Observable Unobservable Balance as of Balance as of Identical Assets Inputs Inputs December 31, December 31, In millions (Level 1) (Level 2) (Level 3) 2023 2023 Assets: Other investments $ - $ - $ 3 $ 3 $ 3 Total assets $ - $ - $ 3 $ 3 $ 3 Liabilities: Long-term debt $ - $ 287 $ - $ 287 $ 2,585 Medium-term notes - - 291 291 455 (1) Investment agreements - - 243 243 221 Liabilities of consolidated VIEs: Variable interest entity loans payable - - 3 3 3 Total liabilities $ - $ 287 $ 537 $ 824 $ 3,264 Financial Guarantees: Gross liability (recoverable) $ - $ - $ 837 $ 837 $ 522 Ceded recoverable (liability) - - 20 20 16 (1) - The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of December 31, 2023, the Company had embedded derivative assets and liabilities of $ 1 million and $ 3 million, respectively. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) The following tables present information about changes in Level 3 assets (including short-term investments) and liabilities measured at fair value on a recurring basis for the three months ended March 31, 2024 and 2023: Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended March 31, 2024 Change in Change in Unrealized Unrealized Gains Gains (Losses) for (Losses) for the Period the Period Included in Included in Total Earnings OCI Gains / Unrealized for Assets for Assets (Losses) Gains / still held still held Balance, Included (Losses) Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (1) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2024 2024 (1) Assets: Corporate obligations $ 1 $ - $ - $ 6 $ - $ - $ - $ - $ - $ 7 (3) $ - $ - Equity investments 108 ( 6 ) - - - - - - - 102 ( 6 ) - Assets of consolidated VIEs: Loans receivable - 35 2 - - - ( 1 ) - - - 36 2 - Other 2 - - - - - - - - 2 - - Total assets $ 146 $ ( 4 ) $ - $ 6 $ - $ ( 1 ) $ - $ - $ - $ 147 $ ( 4 ) $ - Change in Change in Unrealized Unrealized (Gains) (Gains) Losses for Losses for the Period the Period Included in Included in Total Unrealized Earnings for OCI for (Gains) / (Gains) / Liabilities Liabilities Losses Losses still held still held Balance, Included Included Transfers Transfers as of as of Beginning in in into out of Ending March 31, March 31, In millions of Period Earnings in OCI (2) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2024 2024 (2) Liabilities: Medium-term notes $ 40 $ ( 2 ) $ ( 2 ) $ - $ - $ - $ - $ - $ - $ 36 $ ( 2 ) $ ( 2 ) Liabilities of consolidated VIEs: VIE notes 78 25 ( 20 ) - - ( 37 ) - - - 46 - ( 1 ) Currency derivatives 14 1 - - - - - - - 15 1 - Total liabilities $ 132 $ 24 $ ( 22 ) $ - $ - $ ( 37 ) $ - $ - $ - $ 97 $ ( 1 ) $ ( 3 ) (1) - Reported within the "Unrealized gains (losses) on available-for-sale securities" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (2) - Reported within the "Instrument-specific credit risk of liabilities measured at fair value" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (3) - Includes loans carried at fair value of $ 6 million. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended March 31, 2023 Change in Change in Unrealized Unrealized Gains Gains (Losses) for (Losses) for the Period the Period Included in Included in Total Earnings for OCI for Gains / Unrealized Assets Assets (Losses) Gains / still held still held Balance, Included (Losses) Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (1) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2023 2023 (1) Assets: Corporate obligations $ - $ - $ - $ - $ - $ - $ - $ 1 $ - $ 1 $ - $ - Equity investments 115 - - - - - - - - 115 - - Assets of consolidated VIEs: Loans receivable- 78 7 - - - ( 2 ) - - - 83 5 - Other 23 2 - - - - ( 16 ) - - 9 1 - Total assets $ 216 $ 9 $ - $ - $ - $ ( 2 ) $ ( 16 ) $ 1 $ - $ 208 $ 6 $ - Change in Change in Unrealized Unrealized (Gains) (Gains) Losses for Losses for the Period the Period Included in Included in Total Earnings for OCI for (Gains) / Unrealized Liabilities Liabilities Losses (Gains) / still held still held Balance, Included Losses Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (2) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2023 2023 (2) Liabilities: Medium-term notes $ 41 $ 3 $ ( 2 ) $ - $ - $ - $ - $ - $ - $ 42 $ 3 $ ( 2 ) Liabilities of consolidated VIEs: VIE notes 172 15 ( 14 ) - - ( 1 ) ( 18 ) - - 154 1 - Currency 6 5 - - - - - - - 11 5 - Total liabilities $ 219 $ 23 $ ( 16 ) $ - $ - $ ( 1 ) $ ( 18 ) $ - $ - $ 207 $ 9 $ ( 2 ) (1) - Reported within the "Unrealized gains (losses) on available-for-sale securities" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (2) - Reported within the "Instrument-specific credit risk of liabilities measured at fair value" on MBIA's Consolidated Statement of Comprehensive Income/Loss. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) For the three months ended March 31, 2024, there were no transfers into or out of Level 3. For the three months ended March 31, 2023, sales include the impact of the deconsolidation of a VIE. Refer to “Note 4: Variable Interest Entities” for additional information about the deconsolidation of VIEs. For the three months ended March 31, 2023, transfers into Level 3 and out of Level 2 were related to corporate obligations, where inputs, which are significant to their valuation, became unobservable during the year. These inputs included spreads, prepayment speeds, default speeds, default severities, yield curves observable at commonly quoted intervals, and market corroborated inputs. There were no transfers out of Level 3. Gains and losses (realized and unrealized) included in earning s related to Level 3 assets and liabilities for the three months ended March 31, 2024 and 2023 are reported on the Company’s consolidated statements of operations as follows: Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Change in Change in Unrealized Unrealized Gains (Losses) Gains (Losses) for the for the Period Included Period Included in Earnings in Earnings for Assets for Assets and and Total Gains Liabilities still Total Gains Liabilities still (Losses) held as of (Losses) held as of Included March 31, Included March 31, In millions in Earnings 2024 in Earnings 2023 Revenues: Net gains (losses) on financial instruments $ ( 4 ) $ ( 4 ) $ ( 3 ) $ ( 3 ) Revenues of consolidated VIEs: Net gains (losses) on financial instruments ( 24 ) 1 3 - Other net realized gains (losses) - - ( 14 ) - Total $ ( 28 ) $ ( 3 ) $ ( 14 ) $ ( 3 ) Derivative Instruments The following table presents the effects of derivative instruments on the Company's consolidated statements of operations for the three months ended March 31, 2024 and 2023: In millions Derivatives Not Designated Three Months Ended March 31, as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivative 2024 2023 Interest rate swaps Net gains (losses) on financial instruments at fair value and foreign exchange $ - $ ( 9 ) Currency swaps-VIE Net gains (losses) on financial instruments at fair value and foreign exchange-VIE ( 1 ) ( 4 ) Total $ ( 1 ) $ ( 13 ) Fair Value Option The Company elected to record at fair value certain financial instruments, including certain equity investments and financial instruments that are consolidated in connection with the adoption of the accounting guidance for consolidation of VIEs. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 6: Fair Value of Financial Instruments (continued) The following table presents the gains and (losses) included in the Company's consolidated statements of operations for the three months ended March 31, 2024 and 2023 for financial instruments for which the fair value option was elected: Three Months Ended March 31, In millions 2024 2023 Investments carried at fair value (1) $ ( 4 ) $ 3 Fixed-maturity securities held at fair value-VIE (2) - ( 4 ) Loans receivable and other instruments at fair value: Residential mortgage loans (2) 2 7 Other assets-VIE (2) - 2 Medium-term notes (1) 2 ( 3 ) Variable interest entity notes (2) ( 25 ) ( 15 ) (1) - Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange" on MBIA's consolidated statements of operations. (2) - Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange-VIE" and "Other net realized gains (losses)-VIE" on MBIA's consolidated statements of operations. The following table reflects the difference between the aggregate fair value and the aggregate remaining contractual principal balance outstanding as of March 31, 2024 and December 31, 2023 for loans and notes for which the fair value option was elected: As of March 31, 2024 As of December 31, 2023 Contractual Contractual Outstanding Fair Outstanding Fair In millions Principal Value Difference Principal Value Difference Loans receivable at fair value: Residential mortgage loans - current $ 17 $ 17 $ - $ 18 $ 18 $ - Residential mortgage loans (90 days or more past due) 59 19 40 58 17 41 Total loans receivable and other instruments at fair value $ 76 $ 36 $ 40 $ 76 $ 35 $ 41 Variable interest entity notes $ 292 $ 46 $ 246 $ 328 $ 78 $ 250 Medium-term notes $ 54 $ 36 $ 18 $ 55 $ 40 $ 15 The differences between the contractual outstanding principal and the fair values on loans receivable, VIE notes and MTNs in the preceding table are primarily attributable to credit risk. This is due to the high rate of defaults on loans (90 days or more past due), the collateral supporting the VIE notes and the nonperformance risk of the Company on its MTNs, all of which resulted in depressed pricing of the financial instruments. Instrument-Specific Credit Risk of Liabilities Elected Under the Fair Value Option As of March 31, 2024 and December 31, 2023 , the cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option were gains of $ 22 million and losses of $ 1 million, respectively, reported in AOCI on the Company’s consolidated balance sheets. Changes in value attributable to instrument-specific credit risk were derived principally from changes in the Company’s credit spread. For liabilities of VIEs, additional adjustments to instrument-specific credit risk are required, which is determined by an analysis of deal specific performance of collateral that support these liabilities. During the three months ended March 31, 2024 and 2023 , the portions of instrument-specific credit risk included in AOCI that were recognized in earnings due to settlement of liabilities were losses of $ 19 million and $ 14 million, respectively.

Investments

Investments	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Investments	Note 7: Inve stments Investments, excluding equity instruments, those elected under the fair value option and those classified as trading, primarily consist of debt instruments classified as AFS. The following tables present the amortized cost, allowance for credit losses, corresponding gross unrealized gains and losses and fair value for AFS investments in the Company’s consolidated investment portfolio as of March 31, 2024 and December 31, 2023: March 31, 2024 Allowance Gross Gross Amortized for Credit Unrealized Unrealized Fair In millions Cost Losses Gains Losses Value AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 567 $ - $ - $ ( 20 ) $ 547 State and municipal bonds 125 - 3 ( 9 ) 119 Foreign governments 14 - 1 ( 2 ) 13 Corporate obligations 511 - 1 ( 98 ) 414 Mortgage-backed securities: Residential mortgage-backed agency 143 - - ( 17 ) 126 Residential mortgage-backed non-agency 31 - 1 ( 6 ) 26 Commercial mortgage-backed 13 - - - 13 Asset-backed securities: Collateralized debt obligations 96 - 1 ( 1 ) 96 Other asset-backed 44 - - ( 1 ) 43 Total AFS investments $ 1,544 $ - $ 7 $ ( 154 ) $ 1,397 December 31, 2023 Allowance Gross Gross Amortized for Credit Unrealized Unrealized Fair In millions Cost Losses Gains Losses Value AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 721 $ - $ 1 $ ( 18 ) $ 704 State and municipal bonds 128 - 3 ( 8 ) 123 Foreign governments 19 - 1 ( 2 ) 18 Corporate obligations 505 - 2 ( 90 ) 417 Mortgage-backed securities: Residential mortgage-backed agency 149 - - ( 14 ) 135 Residential mortgage-backed non-agency 31 - 1 ( 5 ) 27 Commercial mortgage-backed 13 - - - 13 Asset-backed securities: Collateralized debt obligations 96 - 1 ( 1 ) 96 Other asset-backed 26 - - ( 2 ) 24 Total AFS investments $ 1,688 $ - $ 9 $ ( 140 ) $ 1,557 MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 7: Investments (continued) The following table presents the distribution by contractual maturity of AFS fixed-maturity securities at amortized cost, net of allowance for credit losses, and fair value as of March 31, 2024. Contractual maturity may differ from expected maturity as borrowers may have the right to call or prepay obligations. AFS Securities Net Amortized Fair In millions Cost Value Due in one year or less $ 418 $ 417 Due after one year through five years 159 155 Due after five years through ten years 205 179 Due after ten years 435 342 Mortgage-backed and asset-backed 327 304 Total fixed-maturity investments $ 1,544 $ 1,397 Deposited and Pledged Securities The fair value of securities on deposit with various regulatory authorities as of March 31, 2024 and December 31, 2023 was $ 11 million. These deposits are required to comply with state insurance laws. Investment agreement obligations require the Company to pledge securities as collateral. Securities pledged in connection with investment agreements may not be repledged by the investment agreement counterparty. As of March 31, 2024 and December 31, 2023 , the fair value of securities pledged as collateral for these investment agreements were $ 230 million and $ 241 million, respectively. The Company’s collateral as of March 31, 2024 consisted principally of U.S. Treasury and government agency and corporate obligations, and was primarily held with major U.S. banks. Impaired Investments The following tables present the non-credit related gross unrealized losses related to AFS investments as of March 31, 2024 and December 31, 2023: March 31, 2024 Less than 12 Months 12 Months or Longer Total Fair Unrealized Fair Unrealized Fair Unrealized In millions Value Losses Value Losses Value Losses AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 25 $ - $ 140 $ ( 20 ) $ 165 $ ( 20 ) State and municipal bonds 27 ( 1 ) 58 ( 8 ) 85 ( 9 ) Foreign governments 2 - 6 ( 2 ) 8 ( 2 ) Corporate obligations 25 ( 1 ) 334 ( 97 ) 359 ( 98 ) Mortgage-backed securities: Residential mortgage-backed agency 9 - 112 ( 17 ) 121 ( 17 ) Residential mortgage-backed non-agency 3 - 21 ( 6 ) 24 ( 6 ) Commercial mortgage-backed - - 3 - 3 - Asset-backed securities: Collateralized debt obligations - - 72 ( 1 ) 72 ( 1 ) Other asset-backed 16 - 17 ( 1 ) 33 ( 1 ) Total AFS investments $ 107 $ ( 2 ) $ 763 $ ( 152 ) $ 870 $ ( 154 ) MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 7: Investments (continued) December 31, 2023 Less than 12 Months 12 Months or Longer Total Fair Unrealized Fair Unrealized Fair Unrealized In millions Value Losses Value Losses Value Losses AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 11 $ - $ 143 $ ( 18 ) $ 154 $ ( 18 ) State and municipal bonds 23 ( 1 ) 57 ( 7 ) 80 ( 8 ) Foreign governments - - 6 ( 2 ) 6 ( 2 ) Corporate obligations 17 - 337 ( 90 ) 354 ( 90 ) Mortgage-backed securities: Residential mortgage-backed agency - - 118 ( 14 ) 118 ( 14 ) Residential mortgage-backed non-agency 3 - 21 ( 5 ) 24 ( 5 ) Commercial mortgage-backed 4 - 3 - 7 - Asset-backed securities: Collateralized debt obligations - - 89 ( 1 ) 89 ( 1 ) Other asset-backed - - 22 ( 2 ) 22 ( 2 ) Total AFS investments $ 58 $ ( 1 ) $ 796 $ ( 139 ) $ 854 $ ( 140 ) Gross unrealized losses on AFS investments increased as of March 31, 2024 compared with December 31, 2023 primarily due to higher interest rates, partially offset by tighter credit spreads. With the weighting applied on the fair value of each security relative to the total fair value, the weighted average contractual maturity of securities in an unrealized loss position as of March 31, 2024 and December 31, 2023 was 14 years . As of March 31, 2024 and December 31, 2023 , there were 433 and 450 securities, respectively, that were in an unrealized loss position for a continuous twelve-month period or longer, of which, fair values of 365 securities were below book value by more than 5 %. The following table presents the distribution of securities in an unrealized loss position for a continuous twelve-month period or longer where fair value was below book value by more than 5% as of March 31, 2024: AFS Securities Percentage of Fair Value Number of Book Value Fair Value Below Book Value Securities (in millions) (in millions) > 5 % to 15 % 176 $ 231 $ 208 > 15 % to 25 % 108 277 226 > 25 % to 50 % 79 227 152 > 50 % 2 - - Total 365 $ 735 $ 586 MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 7: Investments (continued) As of March 31, 2024, the Company concluded that it does not have the intent to sell securities in an unrealized loss position and it is more likely than not, that it would not have to sell these securities before recovery of their cost basis. In making this conclusion, the Company examined the cash flow projections for its investment portfolios, the potential sources and uses of cash in its businesses, and the cash resources available to its business other than sales of securities. It also considered the existence of any risk management or other plans as of March 31, 2024 that would require the sale of impaired securities. Credit Losses on Investments The Company’s fixed-maturity securities for which fair value is less than amortized cost are reviewed quarterly in order to determine whether a credit loss exists. If the Company determines that the declines in the fair value are related to credit loss, the Company will establish an allowance for credit losses and recognize the credit component through earnings. Refer to “Note 8: Investments” in the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 for a discussion of the Company’s policy for its determination of credit losses. The Company did not purchase any credit-deteriorated assets or establish an allowance for credit losses for AFS securities for the three months ended March 31, 2024. The Company does not recognize credit losses on securities insured by MBIA Corp. and National since those securities, whether or not owned by the Company, are evaluated for impairments in accordance with its loss reserving policy. The following table provides information about securities held by the Company as of March 31, 2024 that were in an unrealized loss position and insured by a financial guarantor, along with the amount of insurance loss reserves corresponding to the par amount owned by the Company. The Company did not hold any securities in an unrealized loss position that were insured by a third-party financial guarantor as of March 31, 2024. Unrealized Insurance Loss In millions Fair Value Loss Reserve (1) Mortgage-backed $ 17 $ ( 4 ) $ 22 Corporate obligations 78 ( 39 ) - Total $ 95 $ ( 43 ) $ 22 (1) - Insurance loss reserve estimates are based on the proportion of par value owned to the total amount of par value insured and are discounted using a discount rate equal to the risk-free rate applicable to the currency and weighted average remaining life of the insurance contract and may differ from the fair value. Sales of Available-for-Sale Investments Gross realized gains and losses from sales of AFS investments are recorded within “Net realized investment gains (losses)”on the Company’s consolidated statements of operations. The proceeds and the gross realized gains and losses from sales of fixed-maturity securities held as AFS for the three months ended March 31, 2024 and 2023 are as follows: Three Months Ended March 31, In millions 2024 2023 Proceeds from sales $ 28 $ 98 Gross realized gains $ - $ 1 Gross realized losses $ ( 1 ) $ ( 4 ) Equity and Trading Investments Equity and trading investments are included within “Investments carried at fair value” on the Company’s consolidated balance sheets. Unrealized gains and losses recognized on equity and trading investments held as of the end of each period for the three months ended March 31, 2024 and 2023 are as follows: Three Months Ended March 31, In millions 2024 2023 Net gains (losses) recognized during the period on equity and trading securities $ ( 2 ) $ 1 Less: Net gains (losses) recognized during the period on equity and trading securities sold during the period - - Unrealized gains (losses) recognized during the period on equity and trading securities still held at the reporting date $ ( 2 ) $ 1

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Note 8: Income Taxes The Company’s income taxes and the related effective tax rates for the three months ended March 31, 2024 and 2023 are as follows: Three Months Ended March 31, In millions 2024 2023 Income (loss) from continuing operations before income taxes $ ( 87 ) $ ( 83 ) Provision (benefit) for income taxes $ - $ - Effective tax rate 0.0 % 0.0 % For the three months ended March 31, 2024 and 2023, the Company’s effective tax rate applied to its loss from continuing operations before income taxes was lower than the U.S. statutory tax rate due to the full valuation allowance on the changes in its net deferred tax asset. Deferred Tax Asset, Net of Valuation Allowance The Company assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of its existing deferred tax assets. A significant piece of objective negative evidence evaluated was the Company having a three-year cumulative loss. Such objective evidence limits the ability to consider other subjective evidence, such as the Company’s projections of pre-tax income. On the basis of this evaluation, the Company has recorded a full valuation allowance against its net deferred tax asset of $ 1.3 billion and $ 1.2 billion as of March 31, 2024 and December 31, 2023. The Company will continue to analyze the valuation allowance on a quarterly basis. Net operating losses (“NOLs”) of property and casualty insurance companies are permitted to be carried back two years and carried forward 20 years. NOLs of property and casualty insurance companies are not subject to the 80 percent taxable income limitation and indefinite lived carryforward period required by the Tax Cuts and Jobs Act applicable to general corporate NOLs. Accounting for Uncertainty in Income Taxes The Company’s policy is to record and disclose any change in unrecognized tax benefit (“UTB”) and related interest and/or penalties to income tax in the consolidated statements of operations. The Company includes interest as a component of income tax expense. As of March 31, 2024 and December 31, 2023 , the Company had no material UTB. Federal income tax returns through 2011 have been examined or surveyed. As of March 31, 2024 , the Company’s NOL is approximately $ 4.2 billion. NOLs generated prior to tax reform and property and casualty NOLs generated after tax reform will expire between tax years 2026 through 2044. As of March 31, 2024 , the Company has a foreign tax credit carryforward of $ 56 million, which will expire between tax years 2024 through 2033. Section 382 of the Internal Revenue Code Included in the Company’s Amended By-Laws are restrictions on certain acquisitions of Company stock that otherwise may have increased the likelihood of an ownership change within the meaning of Section 382 of the Internal Revenue Code. With certain exceptions, the By-Laws generally prohibit a person from becoming a “Section 382 five-percent shareholder” by acquiring, directly or by attribution, 5% or more of the outstanding shares of the Company’s common stock.

Business Segments

Business Segments	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Business Segments	Note 9: Business Segments As defined by segment reporting, an operating segment is a component of a company (i) that engages in business activities from which it earns revenue and incurs expenses, (ii) whose operating results are regularly reviewed by the Chief Operating Decision Maker to assess the performance of the segment and to make decisions about the allocation of resources to the segment and, (iii) for which discrete financial information is available. The Company manages its businesses across three operating segments: 1) U.S. public finance insurance; 2) corporate; and 3) international and structured finance insurance. The Company’s U.S. public finance insurance business is operated through National and its international and structured finance insurance business is operated through MBIA Corp. The following sections provide a description of each of the Company’s reportable operating segments. U.S. Public Finance Insurance The Company’s U.S. public finance insurance portfolio is managed through National. The financial guarantees issued by National provide unconditional and irrevocable guarantees of the payment of the principal of, and interest or other amounts owing on, U.S. public finance insured obligations when due. The obligations are not subject to acceleration, except that National may have the right, at its discretion, to accelerate insured obligations upon default or otherwise. National’s guarantees insure municipal bonds, including tax-exempt and taxable indebtedness of U.S. political subdivisions, as well as utilities, airports, health care institutions, higher educational facilities, housing authorities and other similar agencies and obligations issued by private entities that finance projects that serve a substantial public purpose. Municipal bonds and privately issued bonds used for the financing of public purpose projects are generally supported by taxes, assessments, fees or tariffs related to the use of these projects, lease payments or other similar types of revenue streams. Corporate The Company’s corporate segment consists of general corporate activities, including providing support services to MBIA Inc.’s subsidiaries as well as asset and capital management. Support services are provided by the Company’s service company, MBIA Services, and include, among others, management, legal, accounting, treasury, information technology, and insurance portfolio surveillance, on a fee-for-service basis. Capital management includes activities related to servicing obligations issued by MBIA Inc. and its subsidiary, MBIA Global Funding, LLC (“GFL”). MBIA Inc. issued debt to finance the operations of the MBIA group. GFL raised funds through the issuance of MTNs with varying maturities, which were in turn guaranteed by MBIA Corp. GFL lent the proceeds of these MTN issuances to MBIA Inc. MBIA Inc. also provided customized investment agreements, guaranteed by MBIA Corp., for bond proceeds and other public funds for such purposes as construction, loan origination, escrow and debt service or other reserve fund requirements. The Company has ceased issuing new MTNs and investment agreements and the outstanding liability balances and corresponding asset balances have declined over time as liabilities matured, terminated or were called or repurchased. All of the debt within the corporate segment is managed collectively and is serviced by available liquidity. International and Structured Finance Insurance The Company’s international and structured finance insurance segment is principally conducted through MBIA Corp. The financial guarantees issued by MBIA Corp. generally provide unconditional and irrevocable guarantees of the payment of principal of, and interest or other amounts owing on, non-U.S. public finance and global structured finance insured obligations when due, or in the event MBIA Corp. has the right, at its discretion, to accelerate insured obligations upon default or otherwise. MBIA Corp. insures non-U.S. public finance and global structured finance obligations, including asset-backed obligations. MBIA Corp. has insured sovereign-related and sub- sovereign bonds, utilities, privately issued bonds used for the financing of projects that include toll roads, bridges, public transportation facilities, and other types of infrastructure projects serving a substantial public purpose. MBIA Corp. has also insured structured finance and asset-backed obligations repayable from expected cash flows generated by a specified pool of assets, such as residential and commercial mortgages, consumer loans, structured settlements, corporate loans and bonds collateralized by such assets. MBIA Corp. insures the investment contracts written by MBIA Inc., and if MBIA Inc. were to have insufficient assets to pay amounts due upon maturity or termination, MBIA Corp. would make such payments. MBIA Insurance Corporation also insures debt obligations of GFL. MBIA Corp. has also written policies guaranteeing obligations under certain derivative contracts, including termination payments that may become due upon certain insolvency or payment defaults of the financial guarantor or the issuer. MBIA Corp. has not written any meaningful amount of business since 2008. MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 9: Business Segments (continued) Segments Results The following tables provide the Company’s segment results for the three months ended March 31, 2024 and 2023: Three Months Ended March 31, 2024 U.S. International Public and Structured Finance Finance In millions Insurance Corporate Insurance Eliminations Consolidated Revenues (1) $ 19 $ 7 $ 7 $ - $ 33 Net gains (losses) on financial instruments at fair value and foreign exchange 1 8 ( 5 ) - 4 Net gains (losses) on extinguishment of debt - 1 - - 1 Revenues of consolidated VIEs - - ( 25 ) - ( 25 ) Inter-segment revenues (2) 6 15 1 ( 22 ) - Total revenues 26 31 ( 22 ) ( 22 ) 13 Losses and loss adjustment 22 - ( 4 ) - 18 Amortization of deferred acquisition costs and operating 2 21 2 1 26 Interest - 13 39 - 52 Expenses of consolidated VIEs - - 4 - 4 Inter-segment expenses (2) 11 6 6 ( 23 ) - Total expenses 35 40 47 ( 22 ) 100 Income (loss) from continuing operations before income taxes $ ( 9 ) $ ( 9 ) $ ( 69 ) $ - $ ( 87 ) Identifiable assets per segment $ 1,720 $ 710 $ 928 $ ( 944 ) (3) $ 2,414 Assets held for sale - - - - 74 Total identifiable assets $ 1,720 $ 710 $ 928 $ ( 944 ) $ 2,488 (1) - Consists of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses). (2) - Primarily represents intercompany service charges and intercompany net investment income and expenses. (3) - Consists principally of intercompany reinsurance balances. Three Months Ended March 31, 2023 In millions U.S. Public Finance Insurance Corporate International and Structured Finance Insurance Eliminations Consolidated Revenues (1) $ 22 $ 5 $ 6 $ - $ 33 Net gains (losses) on financial instruments at fair value and foreign exchange 2 ( 12 ) ( 3 ) - ( 13 ) Revenues of consolidated VIEs - - ( 18 ) - ( 18 ) Inter-segment revenues (2) 7 14 2 ( 23 ) - Total revenues 31 7 ( 13 ) ( 23 ) 2 Losses and loss adjustment - - 6 - 6 Amortization of deferred acquisition costs and operating 2 18 3 1 24 Interest - 14 37 - 51 Expenses of consolidated VIEs - - 4 - 4 Inter-segment expenses (2) 12 6 6 ( 24 ) - Total expenses 14 38 56 ( 23 ) 85 Income (loss) from continuing operations before income taxes $ 17 $ ( 31 ) $ ( 69 ) $ - $ ( 83 ) (1) - Consists of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses). (2) - Primarily represents intercompany service charges and intercompany net investment income and expenses.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Earnings Per Share	Note 10: Earnings Per Share Earnings per share is calculated using the two-class method in which earnings are allocated to common stock and participating securities based on their rights to receive nonforfeitable dividends or dividend equivalents. The Company grants restricted stock to certain employees and non-employee directors in accordance with the Company’s long-term incentive programs, which entitle the participants to receive nonforfeitable dividends or dividend equivalents during the vesting period on the same basis as those dividends are paid to common shareholders. These unvested stock awards represent participating securities. During periods of net income, the calculation of earnings per share exclude the income attributable to participating securities in the numerator and the dilutive impact of these securities from the denominator. During periods of net loss, no effect is given to participating securities in the numerator and the denominator excludes the dilutive impact of these securities since they do not share in the losses of the Company. Basic earnings per share excludes dilution and is reported separately for continuing operations and discontinued operations. Basic earnings per share for continuing operations and discontinued operations is computed by dividing net income from continuing operations and discontinued operations available to common shareholders by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflects the dilutive effect of all unvested restricted stock outstanding during the period that could potentially result in the issuance of common stock. The dilution from unvested restricted stock is calculated by applying the two-class method and using the treasury stock method. The treasury stock method assumes the proceeds from the unrecognized compensation expense from unvested restricted stock will be used to purchase shares of the Company’s common stock at the average market price during the period. If the potentially dilutive securities disclosed in the table below become vested, the transaction would be net share settled resulting in a significantly lower impact to the outstanding share balance in comparison to the total amount of the potentially dilutive securities. During periods of net loss, unvested restricted stock is excluded from the calculation because it would have an antidilutive effect. Therefore, in periods of net loss, the calculation of basic and diluted earnings per share would result in the same value. The following table presents the computation of basic and diluted earnings per share for the three months ended March 31, 2024 and 2023: Three Months Ended March 31, In millions except per share amounts 2024 2023 Basic and diluted earnings per share: Net income (loss) from continuing operations available to common shareholders $ ( 87 ) $ ( 83 ) Income (loss) from discontinued operations, net of income taxes 1 ( 3 ) Less: Net income (loss) from discontinued operations attributable to noncontrolling interests - 7 Net income (loss) from discontinued operations attributable to MBIA Inc. 1 ( 10 ) Net income (loss) attributable to MBIA Inc. $ ( 86 ) $ ( 93 ) Basic and diluted weighted average shares (1) 46.8 49.9 Net income (loss) per common share attributable to MBIA Inc. - basic and diluted: Continuing operations $ ( 1.88 ) $ ( 1.67 ) Discontinued operations 0.04 ( 0.19 ) Net income (loss) per share attributable to MBIA Inc. - basic and diluted $ ( 1.84 ) $ ( 1.86 ) Potentially dilutive securities excluded from the calculation of diluted EPS because of antidilutive affect 4.0 4.9 (1) - Includes approximately 1 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended March 31, 2024 and 2023 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Accumulated Other Comprehensive Income	The following table presents the changes in the components of AOCI for the three months ended March 31, 2024: In millions Unrealized Gains (Losses) on AFS Securities, Net Foreign Current Translation, Net Instrument-Specific Credit Risk of Liabilities Measured at Fair Value, Net Total Balance, December 31, 2023 $ ( 134 ) $ ( 4 ) $ ( 1 ) $ ( 139 ) Other comprehensive income (loss) before reclassifications ( 15 ) - 4 ( 11 ) Amounts reclassified from AOCI - - 19 19 Net period other comprehensive income (loss) ( 15 ) - 23 8 Balance, March 31, 2024 $ ( 149 ) $ ( 4 ) $ 22 $ ( 131 ) The following table presents the details of the reclassifications from AOCI for the three months ended March 31, 2024 and 2023: In millions Amounts Reclassified from AOCI Three Months Ended March 31, Details about AOCI Components 2024 2023 Affected Line Item on the Consolidated Statements of Operations Unrealized gains (losses) on AFS securities: Realized gains (losses) on sale of securities $ - $ ( 5 ) Net realized investment gains (losses) Instrument-specific credit risk of liabilities: Deconsolidation of VIE - ( 14 ) Other net realized gains (losses) - VIE Settlement of liabilities ( 19 ) - Net gains (losses) on financial instruments at fair value and foreign exchange - VIE Total reclassifications for the period $ ( 19 ) $ ( 19 ) Net income (loss)

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Commitments and Contingencies	Note 12: Commitments and Contingencies The following commitments and contingencies provide an update of those discussed in “Note 19: Commitments and Contingencies” in the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, and should be read in conjunction with the complete descriptions provided in the aforementioned Form 10-K. Litigation Refer to “Note 1: Business Developments and Risks and Uncertainties ” for further information regarding PREPA's Title III proceedings. There are otherwise no material legal proceedings pending or, to the knowledge of the Company, threatened, to which the Company or any of its subsidiaries is a party. Lease Commitments The Company has a lease agreement for its headquarters in Purchase, New York. The initial lease term expires in 2030 with the option to terminate the lease in 2025 upon the payment of a termination amount. This lease agreement included an incentive amount to fund certain leasehold improvements, renewal options, escalation clauses and a free rent period. This lease agreement has been classified as an operating lease, and operating rent expense is recognized on a straight-line basis. The following table provides information about the Company’s leases as of March 31, 2024: $ in millions As of March 31, 2024 Balance Sheet Location Right-of-use asset $ 15 Other assets Lease liability $ 15 Other liabilities Weighted average remaining lease term (years) 6.4 Discount rate used for operating leases 7.5 % Total future minimum lease payments $ 19 Other Commitment  6 million. During the three months ended March 31, 2024, $ 6 million was drawn under this loan. Subsequent to March 31, 2024, the term loan was amended to increase MBIA Corp.'s commitment by $ 4 million, which was fully drawn.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X and, accordingly, do not include all of the information and disclosures required by accounting principles generally accepted in the United States of America (“GAAP”) for annual periods. These statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Annual Report on Form 10-K for the year ended December 31, 2023. The accompanying consolidated financial statements have not been audited by an independent registered public accounting firm in accordance with the standards of the Public Company Accounting Oversight Board (U.S.), but in the opinion of management such financial statements include all adjustments, consisting only of normal recurring adjustments, necessary for the fair statement of the Company’s consolidated financial position and results of operations. All material intercompany balances and transactions have been eliminated. Certain amounts have been reclassified in prior years' financial statements to conform to the current presentation. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. As additional information becomes available or actual amounts become determinable, the recorded estimates are revised and reflected in operating results. The results of operations for the three months ended March 31, 2024 may not be indicative of the results that may be expected for the year ending December 31, 2024. The December 31, 2023 consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP for annual periods.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards The Company has not adopted any new accounting pronouncements that had a material impact on its consolidated financial statements.

Business Developments and Ris_2

Business Developments and Risks and Uncertainties (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Schedule of Discontinued Operations Components of Assets and Liabilities Held for Sale	The following table summarizes the components of assets and liabilities held for sale: As of In millions March 31, 2024 December 31, 2023 Assets held for sale Cash $ 1 $ 1 Accounts receivable 16 17 Goodwill 90 90 Other assets 9 9 Loss on disposal group ( 42 ) ( 44 ) Total assets held for sale $ 74 $ 73 Liabilities held for sale Accounts payable $ 6 $ 7 Debt 40 39 Accrued expenses and other 18 18 Total liabilities held for sale $ 64 $ 64
Schedule of Results of Operations from Discontinued Operation	The results of operations from discontinued operations for the three months ended March 31, 2024 and 2023 consist of the following: Three Months Ended March 31, In millions 2024 2023 Revenues: Revenues $ 24 $ 32 Cost of sales 11 17 Total revenues from discontinued operations 13 15 Expenses: Operating 13 20 Interest 1 1 Increase (decrease) on loss on disposal group ( 2 ) ( 3 ) Total expenses from discontinued operations 12 18 Income (loss) before income taxes from discontinued operations 1 ( 3 ) Provision (benefit) for income taxes from discontinued operations - - Income (loss) from discontinued operations, net of income taxes $ 1 $ ( 3 )

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Summary of Nonconsolidated VIEs Assets and Liabilities	March 31, 2024 Carrying Value of Assets Carrying Value of Liabilities In millions Maximum Exposure to Loss Investments Premiums Receivable Insurance Loss Recoverable Unearned Premium Revenue Loss and Loss Adjustment Expense Reserves Insurance: Global structured finance: Mortgage-backed residential $ 838 $ 19 $ 5 $ 21 $ 3 $ 232 Consumer asset-backed 111 - - 1 - 3 Corporate asset-backed 391 - 2 7 3 - Total global structured finance 1,340 19 7 29 6 235 Global public finance 210 - 4 - 3 - Total insurance $ 1,550 $ 19 $ 11 $ 29 $ 9 $ 235 December 31, 2023 Carrying Value of Assets Carrying Value of Liabilities In millions Maximum Exposure to Loss Investments Premiums Receivable Insurance Loss Recoverable Unearned Premium Revenue Loss and Loss Adjustment Expense Reserves Insurance: Global structured finance: Mortgage-backed residential $ 853 $ 19 $ 5 $ 23 $ 3 $ 239 Consumer asset-backed 121 - - 1 - 3 Corporate asset-backed 402 - 2 7 3 - Total global structured finance 1,376 19 7 31 6 242 Global public finance 218 - 4 - 4 - Total insurance $ 1,594 $ 19 $ 11 $ 31 $ 10 $ 242

Loss and Loss Adjustment Expe_2

Loss and Loss Adjustment Expense Reserves (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Present Value Of The Probability-Weighted Future Claim Payments And Recoveries	The Company’s loss and LAE reserves and recoveries before consolidated VIE eliminations, along with amounts that were eliminated as a result of consolidating VIEs for the international and structured finance insurance segment, which are included in the Company’s consolidated balance sheets as of March 31, 2024 and December 31, 2023 are presented in the following table: As of March 31, 2024 As of December 31, 2023 In millions Balance Sheet Line Item Balance Sheet Line Item Insurance loss recoverable Loss and LAE reserves (1) Insurance loss recoverable Loss and LAE reserves (1) U.S. Public Finance Insurance $ 150 $ 234 $ 152 $ 230 International and Structured Finance Insurance: Before VIE eliminations 30 321 32 335 VIE eliminations ( 1 ) ( 85 ) ( 1 ) ( 92 ) Total international and structured finance insurance 29 236 31 243 Total $ 179 $ 470 $ 183 $ 473 (1) - Amounts are net of estimated recoveries of expected future claims.
Schedule Of Loss And Loss Adjustment Expenses Reserves	In millions Changes in Loss and LAE Reserves for the Three Months Ended March 31, 2024 Gross Loss Gross Loss and LAE Accretion Changes in and LAE Reserves as of Loss of Claim Changes in Unearned Reserves as of December 31, and LAE Liability Discount Changes in Premium March 31, 2023 Payments Discount Rates Assumptions (1) Revenue 2024 $ 473 $ ( 19 ) $ 4 $ ( 11 ) $ 26 $ ( 3 ) $ 470 (1) - Includes changes in amount and timing of estimated payments and recoveries.
Schedule Of Insurance Loss Recoverable	Changes in Insurance Loss Recoverable for the Three Months Ended March 31, 2024 Gross Gross Recoverable Recoverable as of Accretion Changes in as of December 31, Collections of Discount Changes in March 31, In millions 2023 for Cases Recoveries Rates Assumptions 2024 Insurance loss recoverable $ 183 $ ( 2 ) $ 2 $ ( 1 ) $ ( 3 ) $ 179
Schedule Of Financial Guarantees And Related Claim Liability	The following table provides information about the financial guarantees and related claim liability included in each of MBIA’s surveillance categories as of March 31, 2024: Surveillance Categories Caution Caution Caution List List List Classified $ in millions Low Medium High List Total Number of policies 30 - - 96 126 Number of issues (1) 11 - - 78 89 Remaining weighted average contract period (in years) 5.9 - - 6.4 6.2 Gross insured contractual payments outstanding: (2) Principal $ 795 $ - $ - $ 1,686 $ 2,481 Interest 1,396 - - 629 2,025 Total $ 2,191 $ - $ - $ 2,315 $ 4,506 Gross Claim Liability (3) $ - $ - $ - $ 852 $ 852 Less: Gross Potential Recoveries (4) - - - 467 467 Discount, net (5) - - - 91 91 Net claim liability (recoverable) $ - $ - $ - $ 294 $ 294 Unearned premium revenue $ 5 $ - $ - $ 10 $ 15 Reinsurance recoverable on paid and unpaid losses (6) $ 13 (1) - An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt. (2) - Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA. (3) - The gross claim liability with respect to Puerto Rico exposures are net of expected recoveries for policies in a net payable position. (4) - Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position. (5) - Represents discount related to Gross Claim Liability and Gross Potential Recoveries. (6) - Included in "Other assets" on the Company's consolidated balance sheets. The following table provides information about the financial guarantees and related claim liability included in each of MBIA’s surveillance categories as of December 31, 2023: Surveillance Categories Caution Caution Caution List List List Classified $ in millions Low Medium High List Total Number of policies 35 - - 94 129 Number of issues (1) 13 - - 77 90 Remaining weighted average contract period (in years) 5.6 - - 7.1 6.3 Gross insured contractual payments outstanding: (2) Principal $ 1,336 $ - $ - $ 1,244 $ 2,580 Interest 1,614 - - 504 2,118 Total $ 2,950 $ - $ - $ 1,748 $ 4,698 Gross Claim Liability (3) $ - $ - $ - $ 651 $ 651 Less: Gross Potential Recoveries (4) - - - 235 235 Discount, net (5) - - - 125 125 Net claim liability (recoverable) $ - $ - $ - $ 291 $ 291 Unearned premium revenue $ 9 $ - $ - $ 7 $ 16 Reinsurance recoverable on paid and unpaid losses (6) $ 13 (1) - An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt. (2) - Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA. (3) - The gross claim liability with respect to Puerto Rico exposures are net of expected recoveries for policies in a net payable position. (4) - Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position. (5) - Represents discount related to Gross Claim Liability and Gross Potential Recoveries. (6) - Included in "Other assets" on the Company's consolidated balance sheets.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Quantitative Information Regarding The Significant Unobservable Inputs For Certain Assets And Liabilities Measured At Fair Value On A Recurring Basis	The following tables provide quantitative information regarding the significant unobservable inputs used by the Company for assets and liabilities measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023: Fair Value as of Range March 31, (Weighted In millions 2024 Valuation Techniques Unobservable Input Average) Assets: Equity Investments $ 102 Discounted cash flow EBITDA multiples (1) Discount rate (1) Weightings (1) Sum of the parts Hard asset values (1) Type certificate values (1) Weightings (1) Loans carried at fair value 6 Discounted cash flow Discount rate (1) Assets of consolidated VIEs: Loans receivable at fair value 36 Market prices of similar liabilities adjusted for financial guarantees provided to VIE obligations Impact of financial guarantee 25 % - 25 % ( 25 %) (2) Liabilities of consolidated VIEs: Variable interest entity notes 46 Market prices of VIE assets adjusted for financial guarantees provided or market prices of similar liabilities Impact of financial guarantee 69 % - 69 % ( 69 %) (2) (1) - Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. (2) - Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value. Fair Value as of Range December 31, (Weighted In millions 2023 Valuation Techniques Unobservable Input Average) Assets: Equity Investments $ 108 Discounted cash flow EBITDA multiples (1) Discount rate (1) Weightings (1) Sum of the parts Hard asset values (1) Type certificate values (1) Weightings (1) Assets of consolidated VIEs: Loans receivable at fair value 35 Market prices of similar liabilities or internal cash flow models adjusted for financial guarantees provided to VIE obligations Impact of financial guarantee 27 % - 27 % ( 27 %) (2) Liabilities of consolidated VIEs: Variable interest entity notes 78 Market prices of VIE assets adjusted for financial guarantees provided or market prices of similar liabilities Impact of financial guarantee 74 % - 74 % ( 74 %) (2) (1) - Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. (2) - Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value.
Company's Assets And Liabilities Measured At Fair Value On Recurring Basis	The following tables present the fair value of the Company’s assets (including short-term investments) and liabilities measured and reported at fair value on a recurring basis as of March 31, 2024 and December 31, 2023: Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Active Markets Other Significant for Identical Observable Unobservable Balance as of Assets Inputs Inputs March 31, In millions (Level 1) (Level 2) (Level 3) 2024 Assets: Fixed-maturity investments: U.S. Treasury and government agency $ 546 $ 7 $ - $ 553 State and municipal bonds - 119 - 119 Foreign governments - 13 - 13 Corporate obligations - 490 7 (1) 497 Mortgage-backed securities: Residential mortgage-backed agency - 140 - 140 Residential mortgage-backed non-agency - 34 - 34 Commercial mortgage-backed - 14 - 14 Asset-backed securities: Collateralized debt obligations - 132 - 132 Other asset-backed - 63 - 63 Total fixed-maturity investments 546 1,012 7 1,565 Money market securities 85 - - 85 Equity investments 43 8 102 153 Cash and cash equivalents 131 - - 131 Assets of consolidated VIEs: Mortgage-backed securities: Residential mortgage-backed non-agency - 10 - 10 Commercial mortgage-backed - 10 - 10 Asset-backed securities: Collateralized debt obligations - 1 - 1 Other asset-backed - 1 - 1 Cash 6 - - 6 Loans receivable at fair value: Residential loans receivable - - 36 36 Other assets - - 2 2 Total assets $ 811 $ 1,042 $ 147 $ 2,000 Liabilities: Medium-term notes $ - $ - $ 36 $ 36 Other liabilities: Insured credit derivatives - 1 - 1 Liabilities of consolidated VIEs: Variable interest entity notes - - 46 46 Currency derivatives - - 15 15 Total liabilities $ - $ 1 $ 97 $ 98 (1) - Includes loans carried at fair value of $ 6 million. Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Active Markets Other Significant for Identical Observable Unobservable Balance as of Assets Inputs Inputs December 31, In millions (Level 1) (Level 2) (Level 3) 2023 Assets: Fixed-maturity investments: U.S. Treasury and government agency $ 705 $ 7 $ - $ 712 State and municipal bonds - 123 - 123 Foreign governments - 18 - 18 Corporate obligations - 496 1 497 Mortgage-backed securities: Residential mortgage-backed agency - 149 - 149 Residential mortgage-backed non-agency - 34 - 34 Commercial mortgage-backed - 14 - 14 Asset-backed securities: Collateralized debt obligations - 146 - 146 Other asset-backed - 46 - 46 Total fixed-maturity investments 705 1,033 1 1,739 Money market securities 34 - - 34 Equity investments 39 8 108 155 Cash and cash equivalents 104 - - 104 Assets of consolidated VIEs: Mortgage-backed securities: Residential mortgage-backed non-agency - 10 - 10 Commercial mortgage-backed - 10 - 10 Asset-backed securities: Collateralized debt obligations - 1 - 1 Other asset-backed - 1 - 1 Cash 3 - - 3 Loans receivable at fair value: Residential loans receivable - - 35 35 Other assets - - 2 2 Total assets $ 885 $ 1,063 $ 146 $ 2,094 Liabilities: Medium-term notes $ - $ - $ 40 $ 40 Other liabilities: Insured credit derivatives - 1 - 1 Non-insured interest rate derivatives - 1 - 1 Liabilities of consolidated VIEs: Variable interest entity notes - - 78 78 Currency derivatives - - 14 14 Total liabilities $ - $ 2 $ 132 $ 134
Fair Value Hierarchy Table Presents The Company's Assets And Liabilities Not Recorded At Fair Value On The Company's Consolidated Balance Sheet	Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Significant Fair Value Carry Value Active Markets for Other Observable Unobservable Balance as of Balance as of Identical Assets Inputs Inputs March 31, March 31, In millions (Level 1) (Level 2) (Level 3) 2024 2024 Assets: Other investments $ - $ - $ 3 $ 3 $ 3 Total assets $ - $ - $ 3 $ 3 $ 3 Liabilities: Long-term debt $ - $ 302 $ - $ 302 $ 2,625 Medium-term notes - - 235 235 418 (1) Investment agreements - - 236 236 220 Liabilities of consolidated VIEs: Variable interest entity loans payable - - 5 5 5 Total liabilities $ - $ 302 $ 476 $ 778 $ 3,268 Financial Guarantees: Gross liability (recoverable) $ - $ - $ 793 $ 793 $ 515 Ceded recoverable (liability) - - 20 20 16 (1) - The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of March 31, 2024, the Company had an immaterial amount of embedded derivative assets and had embedded derivative liabilities of $ 2 million. Fair Value Measurements at Reporting Date Using Quoted Prices in Significant Significant Fair Value Carry Value Active Markets for Other Observable Unobservable Balance as of Balance as of Identical Assets Inputs Inputs December 31, December 31, In millions (Level 1) (Level 2) (Level 3) 2023 2023 Assets: Other investments $ - $ - $ 3 $ 3 $ 3 Total assets $ - $ - $ 3 $ 3 $ 3 Liabilities: Long-term debt $ - $ 287 $ - $ 287 $ 2,585 Medium-term notes - - 291 291 455 (1) Investment agreements - - 243 243 221 Liabilities of consolidated VIEs: Variable interest entity loans payable - - 3 3 3 Total liabilities $ - $ 287 $ 537 $ 824 $ 3,264 Financial Guarantees: Gross liability (recoverable) $ - $ - $ 837 $ 837 $ 522 Ceded recoverable (liability) - - 20 20 16 (1) - The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of December 31, 2023, the Company had embedded derivative assets and liabilities of $ 1 million and $ 3 million, respectively.
Changes In Level 3 Assets Measured At Fair Value On A Recurring Basis	Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended March 31, 2024 Change in Change in Unrealized Unrealized Gains Gains (Losses) for (Losses) for the Period the Period Included in Included in Total Earnings OCI Gains / Unrealized for Assets for Assets (Losses) Gains / still held still held Balance, Included (Losses) Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (1) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2024 2024 (1) Assets: Corporate obligations $ 1 $ - $ - $ 6 $ - $ - $ - $ - $ - $ 7 (3) $ - $ - Equity investments 108 ( 6 ) - - - - - - - 102 ( 6 ) - Assets of consolidated VIEs: Loans receivable - 35 2 - - - ( 1 ) - - - 36 2 - Other 2 - - - - - - - - 2 - - Total assets $ 146 $ ( 4 ) $ - $ 6 $ - $ ( 1 ) $ - $ - $ - $ 147 $ ( 4 ) $ - Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended March 31, 2023 Change in Change in Unrealized Unrealized Gains Gains (Losses) for (Losses) for the Period the Period Included in Included in Total Earnings for OCI for Gains / Unrealized Assets Assets (Losses) Gains / still held still held Balance, Included (Losses) Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (1) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2023 2023 (1) Assets: Corporate obligations $ - $ - $ - $ - $ - $ - $ - $ 1 $ - $ 1 $ - $ - Equity investments 115 - - - - - - - - 115 - - Assets of consolidated VIEs: Loans receivable- 78 7 - - - ( 2 ) - - - 83 5 - Other 23 2 - - - - ( 16 ) - - 9 1 - Total assets $ 216 $ 9 $ - $ - $ - $ ( 2 ) $ ( 16 ) $ 1 $ - $ 208 $ 6 $ -
Changes In Level 3 Liabilities Measured At Fair Value On A Recurring Basis	Change in Change in Unrealized Unrealized (Gains) (Gains) Losses for Losses for the Period the Period Included in Included in Total Unrealized Earnings for OCI for (Gains) / (Gains) / Liabilities Liabilities Losses Losses still held still held Balance, Included Included Transfers Transfers as of as of Beginning in in into out of Ending March 31, March 31, In millions of Period Earnings in OCI (2) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2024 2024 (2) Liabilities: Medium-term notes $ 40 $ ( 2 ) $ ( 2 ) $ - $ - $ - $ - $ - $ - $ 36 $ ( 2 ) $ ( 2 ) Liabilities of consolidated VIEs: VIE notes 78 25 ( 20 ) - - ( 37 ) - - - 46 - ( 1 ) Currency derivatives 14 1 - - - - - - - 15 1 - Total liabilities $ 132 $ 24 $ ( 22 ) $ - $ - $ ( 37 ) $ - $ - $ - $ 97 $ ( 1 ) $ ( 3 ) (1) - Reported within the "Unrealized gains (losses) on available-for-sale securities" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (2) - Reported within the "Instrument-specific credit risk of liabilities measured at fair value" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (3) - Includes loans carried at fair value of $ 6 million. Change in Change in Unrealized Unrealized (Gains) (Gains) Losses for Losses for the Period the Period Included in Included in Total Earnings for OCI for (Gains) / Unrealized Liabilities Liabilities Losses (Gains) / still held still held Balance, Included Losses Transfers Transfers as of as of Beginning in Included into out of Ending March 31, March 31, In millions of Period Earnings in OCI (2) Purchases Issuances Settlements Sales Level 3 Level 3 Balance 2023 2023 (2) Liabilities: Medium-term notes $ 41 $ 3 $ ( 2 ) $ - $ - $ - $ - $ - $ - $ 42 $ 3 $ ( 2 ) Liabilities of consolidated VIEs: VIE notes 172 15 ( 14 ) - - ( 1 ) ( 18 ) - - 154 1 - Currency 6 5 - - - - - - - 11 5 - Total liabilities $ 219 $ 23 $ ( 16 ) $ - $ - $ ( 1 ) $ ( 18 ) $ - $ - $ 207 $ 9 $ ( 2 ) (1) - Reported within the "Unrealized gains (losses) on available-for-sale securities" on MBIA's Consolidated Statement of Comprehensive Income/Loss. (2) - Reported within the "Instrument-specific credit risk of liabilities measured at fair value" on MBIA's Consolidated Statement of Comprehensive Income/Loss.
Gains And Losses (Realized And Unrealized) Included In Earnings Pertaining To Level 3 Assets And Liabilities	Gains and losses (realized and unrealized) included in earning s related to Level 3 assets and liabilities for the three months ended March 31, 2024 and 2023 are reported on the Company’s consolidated statements of operations as follows: Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Change in Change in Unrealized Unrealized Gains (Losses) Gains (Losses) for the for the Period Included Period Included in Earnings in Earnings for Assets for Assets and and Total Gains Liabilities still Total Gains Liabilities still (Losses) held as of (Losses) held as of Included March 31, Included March 31, In millions in Earnings 2024 in Earnings 2023 Revenues: Net gains (losses) on financial instruments $ ( 4 ) $ ( 4 ) $ ( 3 ) $ ( 3 ) Revenues of consolidated VIEs: Net gains (losses) on financial instruments ( 24 ) 1 3 - Other net realized gains (losses) - - ( 14 ) - Total $ ( 28 ) $ ( 3 ) $ ( 14 ) $ ( 3 )
Effects Of Derivative Instruments On Consolidated Statements Of Operations	The following table presents the effects of derivative instruments on the Company's consolidated statements of operations for the three months ended March 31, 2024 and 2023: In millions Derivatives Not Designated Three Months Ended March 31, as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivative 2024 2023 Interest rate swaps Net gains (losses) on financial instruments at fair value and foreign exchange $ - $ ( 9 ) Currency swaps-VIE Net gains (losses) on financial instruments at fair value and foreign exchange-VIE ( 1 ) ( 4 ) Total $ ( 1 ) $ ( 13 )
Changes In Fair Value Included In The Company's Consolidated Statements Of Operations	The following table presents the gains and (losses) included in the Company's consolidated statements of operations for the three months ended March 31, 2024 and 2023 for financial instruments for which the fair value option was elected: Three Months Ended March 31, In millions 2024 2023 Investments carried at fair value (1) $ ( 4 ) $ 3 Fixed-maturity securities held at fair value-VIE (2) - ( 4 ) Loans receivable and other instruments at fair value: Residential mortgage loans (2) 2 7 Other assets-VIE (2) - 2 Medium-term notes (1) 2 ( 3 ) Variable interest entity notes (2) ( 25 ) ( 15 ) (1) - Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange" on MBIA's consolidated statements of operations. (2) - Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange-VIE" and "Other net realized gains (losses)-VIE" on MBIA's consolidated statements of operations.
Difference Between Aggregate Fair Value And The Aggregate Remaining Contractual Principal Balance Outstanding	The following table reflects the difference between the aggregate fair value and the aggregate remaining contractual principal balance outstanding as of March 31, 2024 and December 31, 2023 for loans and notes for which the fair value option was elected: As of March 31, 2024 As of December 31, 2023 Contractual Contractual Outstanding Fair Outstanding Fair In millions Principal Value Difference Principal Value Difference Loans receivable at fair value: Residential mortgage loans - current $ 17 $ 17 $ - $ 18 $ 18 $ - Residential mortgage loans (90 days or more past due) 59 19 40 58 17 41 Total loans receivable and other instruments at fair value $ 76 $ 36 $ 40 $ 76 $ 35 $ 41 Variable interest entity notes $ 292 $ 46 $ 246 $ 328 $ 78 $ 250 Medium-term notes $ 54 $ 36 $ 18 $ 55 $ 40 $ 15

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Amortized Cost And Fair Value Of Available-For-Sale And Held-To-Maturity Investment Portfolios	The following tables present the amortized cost, allowance for credit losses, corresponding gross unrealized gains and losses and fair value for AFS investments in the Company’s consolidated investment portfolio as of March 31, 2024 and December 31, 2023: March 31, 2024 Allowance Gross Gross Amortized for Credit Unrealized Unrealized Fair In millions Cost Losses Gains Losses Value AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 567 $ - $ - $ ( 20 ) $ 547 State and municipal bonds 125 - 3 ( 9 ) 119 Foreign governments 14 - 1 ( 2 ) 13 Corporate obligations 511 - 1 ( 98 ) 414 Mortgage-backed securities: Residential mortgage-backed agency 143 - - ( 17 ) 126 Residential mortgage-backed non-agency 31 - 1 ( 6 ) 26 Commercial mortgage-backed 13 - - - 13 Asset-backed securities: Collateralized debt obligations 96 - 1 ( 1 ) 96 Other asset-backed 44 - - ( 1 ) 43 Total AFS investments $ 1,544 $ - $ 7 $ ( 154 ) $ 1,397 December 31, 2023 Allowance Gross Gross Amortized for Credit Unrealized Unrealized Fair In millions Cost Losses Gains Losses Value AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 721 $ - $ 1 $ ( 18 ) $ 704 State and municipal bonds 128 - 3 ( 8 ) 123 Foreign governments 19 - 1 ( 2 ) 18 Corporate obligations 505 - 2 ( 90 ) 417 Mortgage-backed securities: Residential mortgage-backed agency 149 - - ( 14 ) 135 Residential mortgage-backed non-agency 31 - 1 ( 5 ) 27 Commercial mortgage-backed 13 - - - 13 Asset-backed securities: Collateralized debt obligations 96 - 1 ( 1 ) 96 Other asset-backed 26 - - ( 2 ) 24 Total AFS investments $ 1,688 $ - $ 9 $ ( 140 ) $ 1,557
Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments	The following table presents the distribution by contractual maturity of AFS fixed-maturity securities at amortized cost, net of allowance for credit losses, and fair value as of March 31, 2024. Contractual maturity may differ from expected maturity as borrowers may have the right to call or prepay obligations. AFS Securities Net Amortized Fair In millions Cost Value Due in one year or less $ 418 $ 417 Due after one year through five years 159 155 Due after five years through ten years 205 179 Due after ten years 435 342 Mortgage-backed and asset-backed 327 304 Total fixed-maturity investments $ 1,544 $ 1,397
Gross Unrealized Losses Related To Available-For-Sale And Held-To-Maturity Investments	The following tables present the non-credit related gross unrealized losses related to AFS investments as of March 31, 2024 and December 31, 2023: March 31, 2024 Less than 12 Months 12 Months or Longer Total Fair Unrealized Fair Unrealized Fair Unrealized In millions Value Losses Value Losses Value Losses AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 25 $ - $ 140 $ ( 20 ) $ 165 $ ( 20 ) State and municipal bonds 27 ( 1 ) 58 ( 8 ) 85 ( 9 ) Foreign governments 2 - 6 ( 2 ) 8 ( 2 ) Corporate obligations 25 ( 1 ) 334 ( 97 ) 359 ( 98 ) Mortgage-backed securities: Residential mortgage-backed agency 9 - 112 ( 17 ) 121 ( 17 ) Residential mortgage-backed non-agency 3 - 21 ( 6 ) 24 ( 6 ) Commercial mortgage-backed - - 3 - 3 - Asset-backed securities: Collateralized debt obligations - - 72 ( 1 ) 72 ( 1 ) Other asset-backed 16 - 17 ( 1 ) 33 ( 1 ) Total AFS investments $ 107 $ ( 2 ) $ 763 $ ( 152 ) $ 870 $ ( 154 ) MBIA Inc. and Subsidiaries Notes to Consolidated Financial Statements (Unaudited) Note 7: Investments (continued) December 31, 2023 Less than 12 Months 12 Months or Longer Total Fair Unrealized Fair Unrealized Fair Unrealized In millions Value Losses Value Losses Value Losses AFS Investments Fixed-maturity investments: U.S. Treasury and government agency $ 11 $ - $ 143 $ ( 18 ) $ 154 $ ( 18 ) State and municipal bonds 23 ( 1 ) 57 ( 7 ) 80 ( 8 ) Foreign governments - - 6 ( 2 ) 6 ( 2 ) Corporate obligations 17 - 337 ( 90 ) 354 ( 90 ) Mortgage-backed securities: Residential mortgage-backed agency - - 118 ( 14 ) 118 ( 14 ) Residential mortgage-backed non-agency 3 - 21 ( 5 ) 24 ( 5 ) Commercial mortgage-backed 4 - 3 - 7 - Asset-backed securities: Collateralized debt obligations - - 89 ( 1 ) 89 ( 1 ) Other asset-backed - - 22 ( 2 ) 22 ( 2 ) Total AFS investments $ 58 $ ( 1 ) $ 796 $ ( 139 ) $ 854 $ ( 140 )
Distribution Of Securities By Percentage Of Fair Value Below Book Value By More Than 5%	The following table presents the distribution of securities in an unrealized loss position for a continuous twelve-month period or longer where fair value was below book value by more than 5% as of March 31, 2024: AFS Securities Percentage of Fair Value Number of Book Value Fair Value Below Book Value Securities (in millions) (in millions) > 5 % to 15 % 176 $ 231 $ 208 > 15 % to 25 % 108 277 226 > 25 % to 50 % 79 227 152 > 50 % 2 - - Total 365 $ 735 $ 586
Securities Held In Unrealized Loss Position And Insured By Financial Guarantor and The Related Insurance Loss Reserve On Company Insured Investments	The following table provides information about securities held by the Company as of March 31, 2024 that were in an unrealized loss position and insured by a financial guarantor, along with the amount of insurance loss reserves corresponding to the par amount owned by the Company. The Company did not hold any securities in an unrealized loss position that were insured by a third-party financial guarantor as of March 31, 2024. Unrealized Insurance Loss In millions Fair Value Loss Reserve (1) Mortgage-backed $ 17 $ ( 4 ) $ 22 Corporate obligations 78 ( 39 ) - Total $ 95 $ ( 43 ) $ 22 (1) - Insurance loss reserve estimates are based on the proportion of par value owned to the total amount of par value insured and are discounted using a discount rate equal to the risk-free rate applicable to the currency and weighted average remaining life of the insurance contract and may differ from the fair value.
Gross Realized Gains and Losses From Sales Of Available-For-Sale Securities	The proceeds and the gross realized gains and losses from sales of fixed-maturity securities held as AFS for the three months ended March 31, 2024 and 2023 are as follows: Three Months Ended March 31, In millions 2024 2023 Proceeds from sales $ 28 $ 98 Gross realized gains $ - $ 1 Gross realized losses $ ( 1 ) $ ( 4 )
Portion Of Unrealized Gains Losses Recognized On Equity Investments	Three Months Ended March 31, In millions 2024 2023 Net gains (losses) recognized during the period on equity and trading securities $ ( 2 ) $ 1 Less: Net gains (losses) recognized during the period on equity and trading securities sold during the period - - Unrealized gains (losses) recognized during the period on equity and trading securities still held at the reporting date $ ( 2 ) $ 1

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income tax rate reconciliation from statutory to effective tax rate	The Company’s income taxes and the related effective tax rates for the three months ended March 31, 2024 and 2023 are as follows: Three Months Ended March 31, In millions 2024 2023 Income (loss) from continuing operations before income taxes $ ( 87 ) $ ( 83 ) Provision (benefit) for income taxes $ - $ - Effective tax rate 0.0 % 0.0 %

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Summary of company's segment results	The following tables provide the Company’s segment results for the three months ended March 31, 2024 and 2023: Three Months Ended March 31, 2024 U.S. International Public and Structured Finance Finance In millions Insurance Corporate Insurance Eliminations Consolidated Revenues (1) $ 19 $ 7 $ 7 $ - $ 33 Net gains (losses) on financial instruments at fair value and foreign exchange 1 8 ( 5 ) - 4 Net gains (losses) on extinguishment of debt - 1 - - 1 Revenues of consolidated VIEs - - ( 25 ) - ( 25 ) Inter-segment revenues (2) 6 15 1 ( 22 ) - Total revenues 26 31 ( 22 ) ( 22 ) 13 Losses and loss adjustment 22 - ( 4 ) - 18 Amortization of deferred acquisition costs and operating 2 21 2 1 26 Interest - 13 39 - 52 Expenses of consolidated VIEs - - 4 - 4 Inter-segment expenses (2) 11 6 6 ( 23 ) - Total expenses 35 40 47 ( 22 ) 100 Income (loss) from continuing operations before income taxes $ ( 9 ) $ ( 9 ) $ ( 69 ) $ - $ ( 87 ) Identifiable assets per segment $ 1,720 $ 710 $ 928 $ ( 944 ) (3) $ 2,414 Assets held for sale - - - - 74 Total identifiable assets $ 1,720 $ 710 $ 928 $ ( 944 ) $ 2,488 (1) - Consists of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses). (2) - Primarily represents intercompany service charges and intercompany net investment income and expenses. (3) - Consists principally of intercompany reinsurance balances. Three Months Ended March 31, 2023 In millions U.S. Public Finance Insurance Corporate International and Structured Finance Insurance Eliminations Consolidated Revenues (1) $ 22 $ 5 $ 6 $ - $ 33 Net gains (losses) on financial instruments at fair value and foreign exchange 2 ( 12 ) ( 3 ) - ( 13 ) Revenues of consolidated VIEs - - ( 18 ) - ( 18 ) Inter-segment revenues (2) 7 14 2 ( 23 ) - Total revenues 31 7 ( 13 ) ( 23 ) 2 Losses and loss adjustment - - 6 - 6 Amortization of deferred acquisition costs and operating 2 18 3 1 24 Interest - 14 37 - 51 Expenses of consolidated VIEs - - 4 - 4 Inter-segment expenses (2) 12 6 6 ( 24 ) - Total expenses 14 38 56 ( 23 ) 85 Income (loss) from continuing operations before income taxes $ 17 $ ( 31 ) $ ( 69 ) $ - $ ( 83 ) (1) - Consists of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses). (2) - Primarily represents intercompany service charges and intercompany net investment income and expenses.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Schedule Of Basic And Diluted Earnings Per Share	The following table presents the computation of basic and diluted earnings per share for the three months ended March 31, 2024 and 2023: Three Months Ended March 31, In millions except per share amounts 2024 2023 Basic and diluted earnings per share: Net income (loss) from continuing operations available to common shareholders $ ( 87 ) $ ( 83 ) Income (loss) from discontinued operations, net of income taxes 1 ( 3 ) Less: Net income (loss) from discontinued operations attributable to noncontrolling interests - 7 Net income (loss) from discontinued operations attributable to MBIA Inc. 1 ( 10 ) Net income (loss) attributable to MBIA Inc. $ ( 86 ) $ ( 93 ) Basic and diluted weighted average shares (1) 46.8 49.9 Net income (loss) per common share attributable to MBIA Inc. - basic and diluted: Continuing operations $ ( 1.88 ) $ ( 1.67 ) Discontinued operations 0.04 ( 0.19 ) Net income (loss) per share attributable to MBIA Inc. - basic and diluted $ ( 1.84 ) $ ( 1.86 ) Potentially dilutive securities excluded from the calculation of diluted EPS because of antidilutive affect 4.0 4.9 (1) - Includes approximately 1 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended March 31, 2024 and 2023 .

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Changes In The Components Of AOCI	The following table presents the changes in the components of AOCI for the three months ended March 31, 2024: In millions Unrealized Gains (Losses) on AFS Securities, Net Foreign Current Translation, Net Instrument-Specific Credit Risk of Liabilities Measured at Fair Value, Net Total Balance, December 31, 2023 $ ( 134 ) $ ( 4 ) $ ( 1 ) $ ( 139 ) Other comprehensive income (loss) before reclassifications ( 15 ) - 4 ( 11 ) Amounts reclassified from AOCI - - 19 19 Net period other comprehensive income (loss) ( 15 ) - 23 8 Balance, March 31, 2024 $ ( 149 ) $ ( 4 ) $ 22 $ ( 131 )
Reclassifications From AOCI	The following table presents the details of the reclassifications from AOCI for the three months ended March 31, 2024 and 2023: In millions Amounts Reclassified from AOCI Three Months Ended March 31, Details about AOCI Components 2024 2023 Affected Line Item on the Consolidated Statements of Operations Unrealized gains (losses) on AFS securities: Realized gains (losses) on sale of securities $ - $ ( 5 ) Net realized investment gains (losses) Instrument-specific credit risk of liabilities: Deconsolidation of VIE - ( 14 ) Other net realized gains (losses) - VIE Settlement of liabilities ( 19 ) - Net gains (losses) on financial instruments at fair value and foreign exchange - VIE Total reclassifications for the period $ ( 19 ) $ ( 19 ) Net income (loss)

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Operating Leases Of Lessee Disclosure	The following table provides information about the Company’s leases as of March 31, 2024: $ in millions As of March 31, 2024 Balance Sheet Location Right-of-use asset $ 15 Other assets Lease liability $ 15 Other liabilities Weighted average remaining lease term (years) 6.4 Discount rate used for operating leases 7.5 % Total future minimum lease payments $ 19

Business Developments And Ris_3

Business Developments And Risks And Uncertainties (Narrative) (Detail) $ in Millions		3 Months Ended
	Jan. 01, 2024 USD ($)	Mar. 31, 2024 USD ($) Segments	Jun. 26, 2023 USD ($)
Business Acquisition [Line Items]
Number of operating segments | Segments		3
Puerto Rico Electric Power Authority [Member]
Business Acquisition [Line Items]
Outstanding insured bonds		$ 792
Maximum [Member]
Business Acquisition [Line Items]
Liabilities Subject to Compromise, Provision for Expected and Allowed Claims			$ 7,600
Minimum [Member]
Business Acquisition [Line Items]
Liabilities Subject to Compromise, Provision for Expected and Allowed Claims			$ 2,400
National Public Finance Guarantee Corporation [Member] | Puerto Rico Electric Power Authority [Member]
Business Acquisition [Line Items]
Claims payments	$ 16

Business Developments and Ris_4

Business Developments and Risks and Uncertainties (Schedule of Discontinued Operations Components of Assets and Liabilities Held for Sale) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets held for sale
Cash	$ 1	$ 1
Accounts receivable	16	17
Goodwill	90	90
Other assets	9	9
Loss on disposal group	(42)	(44)
Total assets held for sale	74	73
Liabilities held for sale
Accounts payable	6	7
Debt	40	39
Accrued expenses and other	18	18
Total liabilities held for sale	$ 64	$ 64

Business Developments and Ris_5

Business Developments and Risks and Uncertainties (Schedule of Results of Operations from Discontinued Operation) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues
Revenues	$ 24	$ 32
Cost of sales	11	17
Total revenues from discontinued operations	13	15
Expenses:
Operating	13	20
Interest	1	1
Increase (decrease) on loss on disposal group	(2)	(3)
Total expenses from discontinued operations	12	18
Income (loss) before income taxes from discontinued operations	1	(3)
Provision (benefit) for income taxes from discontinued operations	0	0
Income (loss) from discontinued operations, net of income taxes	$ 1	$ (3)

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Detail) - Variable Interest Entity, Primary Beneficiary [Member] - Structured Finance and International Insurance [Member] $ in Millions	3 Months Ended
	Mar. 31, 2024 VariableInterestEntities	Mar. 31, 2023 USD ($) VariableInterestEntities
Variable Interest Entity [Line Items]
Number of variable interest entities deconsolidated	0	1
Number of variable interest entities consolidated	0	0
Recorded Due To Credit Losses in AOCI [Member]
Variable Interest Entity [Line Items]
Net realized gains (losses) related to deconsolidation | $		$ 15

Variable Interest Entities (Sum

Variable Interest Entities (Summary of Nonconsolidated VIEs Assets and Liabilities) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	$ 1,550	$ 1,594
Carrying Value of VIE Assets	2,488	2,606
Carrying Value of VIE Liabilities	4,211	4,253
Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	19	19
Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	11	11
Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	29	31
Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	9	10
Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	235	242
Global Structured Finance [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	1,340	1,376
Global Structured Finance [Member] | Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	19	19
Global Structured Finance [Member] | Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	7	7
Global Structured Finance [Member] | Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	29	31
Global Structured Finance [Member] | Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	6	6
Global Structured Finance [Member] | Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	235	242
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	838	853
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	19	19
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	5	5
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	21	23
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	3	3
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	232	239
Global Structured Finance [Member] | Consumer Asset Backed [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	111	121
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	0	0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	0	0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	1	1
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	0	0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	3	3
Global Structured Finance [Member] | Corporate Asset Backed [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	391	402
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	0	0
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	2	2
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	7	7
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	3	3
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	0	0
Global Public Finance [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	210	218
Global Public Finance [Member] | Investments [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	0	0
Global Public Finance [Member] | Premiums Receivable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	4	4
Global Public Finance [Member] | Insurance Loss Recoverable [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Assets	0	0
Global Public Finance [Member] | Unearned Premium Revenue [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	3	4
Global Public Finance [Member] | Loss And Loss Adjustment Expense Reserves [Member]
Variable Interest Entity [Line Items]
Carrying Value of VIE Liabilities	$ 0	$ 0

Loss and Loss Adjustment Expe_3

Loss and Loss Adjustment Expense Reserves (Schedule of Losses and Loss Adjustment Expenses Reserves and Recoveries) (Detail) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Loss And Lae Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	[1]	$ 470	$ 473
Insurance Loss Recoverable [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		179	183
Non Variable Interest Entity [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		179	183
Loss and loss adjustment expense reserves		470	473
US Public Finance Insurance [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		150	152
Loss and loss adjustment expense reserves	[1]	234	230
International And Structured Finance Insurance [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		30	32
Loss and loss adjustment expense reserves	[1]	321	335
International And Structured Finance Insurance [Member] | Non Variable Interest Entity [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		29	31
Loss and loss adjustment expense reserves	[1]	236	243
Consolidation Elimination [Member] | International And Structured Finance Insurance [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance Loss Recoverable		(1)	(1)
Loss and loss adjustment expense reserves	[1]	$ (85)	$ (92)
[1] Amounts are net of estimated recoveries of expected future claims.

Loss and Loss Adjustment Expe_4

Loss and Loss Adjustment Expense Reserves (Loss and LAE Activity) (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Loss And Loss Adjustment Expense Reserves [Line Items]
Weighted average risk-free rates used to discount claim liability	4.33%		3.97%
Lae [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Losses and loss adjustment	$ 2	$ 2
Loss and loss adjustment expense reserves	$ 8		$ 8
Changes in Loss and LAE Reserves	one-year

Loss and Loss Adjustment Expe_5

Loss and Loss Adjustment Expense Reserves (Schedule of Loss and Loss Adjustment Expenses Reserves) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Loss And Loss Adjustment Expense Reserves [Line Items]
Changes in unearned premium revenue		$ 8	$ 9
Loss And Lae Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Gross loss and LAE reserve, beginning balance	[1]	473
Loss payments for cases		(19)
Accretion of claim liability discount		4
Changes in discount rates		(11)
Changes in assumptions	[2]	26
Changes in unearned premium revenue		(3)
Gross loss and LAE reserve, ending balance	[1]	$ 470
[1] Amounts are net of estimated recoveries of expected future claims. Includes changes in amount and timing of estimated payments and recoveries.

Loss and Loss Adjustment Expe_6

Loss and Loss Adjustment Expense Reserves (Schedule of Insurance Loss Recoverable) (Detail) - Insurance Loss Recoverable [Member] $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Roll forward of Insurance Loss Recoverable [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	$ 183
Collections for Cases	(2)
Accretion of Recoveries	2
Changes in Discount Rates	(1)
Changes in Assumptions	(3)
Gross Reserve ending balance, Insurance loss recoverable	$ 179

Loss and Loss Adjustment Expe_7

Loss and Loss Adjustment Expense Reserves (Schedule Of Financial Guarantees And Related Claim Liability) (Detail) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2024 USD ($) Issue Policy	Dec. 31, 2023 USD ($) Issue Policy
Loss And Loss Adjustment Expense Reserves [Line Items]
Number of policies | Policy		126	129
Number of issues | Issue	[1]	89	90
Remaining weighted average contract period (in years)		6 years 2 months 12 days	6 years 3 months 18 days
Principal	[2]	$ 2,481	$ 2,580
Interest	[2]	2,025	2,118
Total	[2]	4,506	4,698
Gross claim liability	[3]	852	651
Less: Gross potential recoveries	[4]	467	235
Discount, net	[5]	91	125
Net claim liability (recoverable)		294	291
Unearned premium revenue		15	16
Reinsurance recoverable on paid and unpaid losses	[6]	$ 13	$ 13
Caution List Low [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Number of policies | Policy		30	35
Number of issues | Issue	[1]	11	13
Remaining weighted average contract period (in years)		5 years 10 months 24 days	5 years 7 months 6 days
Principal	[2]	$ 795	$ 1,336
Interest	[2]	1,396	1,614
Total	[2]	2,191	2,950
Gross claim liability	[3]	0	0
Less: Gross potential recoveries	[4]	0	0
Discount, net	[5]	0	0
Net claim liability (recoverable)		0	0
Unearned premium revenue		$ 5	$ 9
Caution List Medium [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Number of policies | Policy		0	0
Number of issues | Issue	[1]	0	0
Principal	[2]	$ 0	$ 0
Interest	[2]	0	0
Total	[2]	0	0
Gross claim liability	[3]	0	0
Less: Gross potential recoveries	[4]	0	0
Discount, net	[5]	0	0
Net claim liability (recoverable)		0	0
Unearned premium revenue		$ 0	$ 0
Caution List High [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Number of policies | Policy		0	0
Number of issues | Issue	[1]	0	0
Principal	[2]	$ 0	$ 0
Interest	[2]	0	0
Total	[2]	0	0
Gross claim liability	[3]	0	0
Less: Gross potential recoveries	[4]	0	0
Discount, net	[5]	0	0
Net claim liability (recoverable)		0	0
Unearned premium revenue		$ 0	$ 0
Classified List [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Number of policies | Policy		96	94
Number of issues | Issue	[1]	78	77
Remaining weighted average contract period (in years)		6 years 4 months 24 days	7 years 1 month 6 days
Principal	[2]	$ 1,686	$ 1,244
Interest	[2]	629	504
Total	[2]	2,315	1,748
Gross claim liability	[3]	852	651
Less: Gross potential recoveries	[4]	467	235
Discount, net	[5]	91	125
Net claim liability (recoverable)		294	291
Unearned premium revenue		$ 10	$ 7
[1] An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt. Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA. The gross claim liability with respect to Puerto Rico exposures are net of expected recoveries for policies in a net payable position. Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position. Represents discount related to Gross Claim Liability and Gross Potential Recoveries. Included in "Other assets" on the Company's consolidated balance sheets.

Fair Value of Financial Instr_3

Fair Value of Financial Instruments (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of level 3 assets at fair value in total assets measured at fair value value	7%		7%
Percentage of level 3 liabilities at fair value in total liabilities measured at fair value	99%		99%
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	$ (131)		$ (139)
Instrument-specific credit risk of liabilities measured at fair value, net [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	22		(1)
Gain (loss) on instrument-specific credit risk recognized in earnings	(19)	$ (14)
Cross Currency Swap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative notional amount	$ 39		$ 39

Fair Value of Financial Instr_4

Fair Value of Financial Instruments (Quantitative Information Regarding The Significant Unobservable Inputs For Certain Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023
Discounted Cash Flow [Member] | Equity Investments [Member] | EBITDA Multiples Discount Rate Hard Asset Values Type Certificate Values [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, assets		$ 102	[1]	$ 108	[2]
Loans Receivable and Other Instruments at Fair Value [Member] | Discounted Cash Flow [Member] | Discount Rate [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, assets	[1]	6
Variable Interest Entity Primary Beneficiary [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value, liabilities		46		78
Variable Interest Entity Primary Beneficiary [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, assets		$ 36
Variable Interest Entity Primary Beneficiary [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities or Internal Cash Flow Models Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, assets				$ 35
Variable Interest Entity Primary Beneficiary [Member] | Minimum [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage		69%	[3]	74%	[4]
Variable Interest Entity Primary Beneficiary [Member] | Minimum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[3]	25%
Variable Interest Entity Primary Beneficiary [Member] | Minimum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities or Internal Cash Flow Models Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[4]			27%
Variable Interest Entity Primary Beneficiary [Member] | Maximum [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage		69%	[3]	74%	[4]
Variable Interest Entity Primary Beneficiary [Member] | Maximum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[3]	25%
Variable Interest Entity Primary Beneficiary [Member] | Maximum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities or Internal Cash Flow Models Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[4]			27%
Variable Interest Entity Primary Beneficiary [Member] | Weighted Average [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage		69%	[3]	74%	[4]
Variable Interest Entity Primary Beneficiary [Member] | Weighted Average [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[3]	25%
Variable Interest Entity Primary Beneficiary [Member] | Weighted Average [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities or Internal Cash Flow Models Adjusted for Financial Guarantees Provided to VIE Obligations [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Range percentage	[4]			27%
[1] Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. Ranges for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful. Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value. Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value.

Fair Value of Financial Instr_5

Fair Value of Financial Instruments (Company's Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) - Fair Value Measurements Recurring [Member] - USD ($) $ in Millions	Mar. 31, 2024		Dec. 31, 2023
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	$ 2,000		$ 2,094
Fair value financial liabilities measured on recurring basis	98		134
Money Market Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	85		34
Medium-term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	36		40
Equity investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	153		155
Cash and Cash Equivalents [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	131		104
Fixed Maturities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1,565		1,739
Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	553		712
Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	119		123
Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	13		18
Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	497		497
Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	140		149
Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	34		34
Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	14		14
Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	132		146
Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	63		46
Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	10		10
Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	10		10
Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1		1
Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1		1
Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	36		35
Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	6		3
Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	2		2
Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	1		1
Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis			1
Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	15		14
Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	46		78
Fair Value Inputs Level 1 [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	811		885
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Money Market Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	85		34
Fair Value Inputs Level 1 [Member] | Medium-term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Equity investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	43		39
Fair Value Inputs Level 1 [Member] | Cash and Cash Equivalents [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	131		104
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	546		705
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	546		705
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	6		3
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis			0
Fair Value Inputs Level 1 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 1 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1,042		1,063
Fair value financial liabilities measured on recurring basis	1		2
Fair Value Inputs Level 2 [Member] | Money Market Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Medium-term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Equity investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	8		8
Fair Value Inputs Level 2 [Member] | Cash and Cash Equivalents [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1,012		1,033
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	7		7
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	119		123
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	13		18
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	490		496
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	140		149
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	34		34
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	14		14
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	132		146
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	63		46
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	10		10
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	10		10
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1		1
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	1		1
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	1		1
Fair Value Inputs Level 2 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis			1
Fair Value Inputs Level 2 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 2 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	147		146
Fair value financial liabilities measured on recurring basis	97		132
Fair Value Inputs Level 3 [Member] | Money Market Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Medium-term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	36		40
Fair Value Inputs Level 3 [Member] | Equity investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	102		108
Fair Value Inputs Level 3 [Member] | Cash and Cash Equivalents [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	7		1
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	7	[1]	1
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	36		35
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial assets measured on recurring basis	2		2
Fair Value Inputs Level 3 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	0		0
Fair Value Inputs Level 3 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis			0
Fair Value Inputs Level 3 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	15		14
Fair Value Inputs Level 3 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Fair value financial liabilities measured on recurring basis	$ 46		$ 78
[1] Includes loans carried at fair value of $ 6 million.

Fair Value of Financial Instr_6

Fair Value of Financial Instruments (Company's Assets And Liabilities Measured At Fair Value On Recurring Basis) (Parenthetical) (Details) $ in Millions	Mar. 31, 2024 USD ($)
Corporate Obligations [Member] | Loans Carried at Fair Value [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable at fair value	$ 6

Fair Value of Financial Instr_7

Fair Value of Financial Instruments (Fair Value Hierarchy Table Presents The Company's Assets And Liabilities At Fair Value Not Recorded On The Company's Consolidated Balance Sheet) (Detail) - Value Disclosed At Fair Value Not Recorded At Fair Value [Member] - Fair Value Measurements Nonrecurring [Member] - USD ($) $ in Millions	Mar. 31, 2024		Dec. 31, 2023
Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Other investments	$ 3		$ 3
Total assets	3		3
Long-term debt	2,625		2,585
Medium-term notes	418	[1]	455	[2]
Investment agreements	220		221
Variable interest entity loans payable	5		3
Total liabilities	3,268		3,264
Gross liability (recoverable)	515		522
Ceded recoverable (liability)	16		16
Fair Value [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Other investments	3		3
Total assets	3		3
Long-term debt	302		287
Medium-term notes	235		291
Investment agreements	236		243
Variable interest entity loans payable	5		3
Total liabilities	778		824
Gross liability (recoverable)	793		837
Ceded recoverable (liability)	20		20
Fair Value [Member] | Fair Value Inputs Level 1 [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Other investments	0		0
Total assets	0		0
Long-term debt	0		0
Medium-term notes	0		0
Investment agreements	0		0
Variable interest entity loans payable	0		0
Total liabilities	0		0
Gross liability (recoverable)	0		0
Ceded recoverable (liability)	0		0
Fair Value [Member] | Fair Value Inputs Level 2 [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Other investments	0		0
Total assets	0		0
Long-term debt	302		287
Medium-term notes	0		0
Investment agreements	0		0
Variable interest entity loans payable	0		0
Total liabilities	302		287
Gross liability (recoverable)	0		0
Ceded recoverable (liability)	0		0
Fair Value [Member] | Fair Value Inputs Level 3 [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Other investments	3		3
Total assets	3		3
Long-term debt	0		0
Medium-term notes	235		291
Investment agreements	236		243
Variable interest entity loans payable	5		3
Total liabilities	476		537
Gross liability (recoverable)	793		837
Ceded recoverable (liability)	$ 20		$ 20
[1] The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of March 31, 2024, the Company had an immaterial amount of embedded derivative assets and had embedded derivative liabilities of $ 2 million. The carry value includes the complex interest calculations embedded derivatives in certain MTNs that are reported together with the host contract. As of December 31, 2023, the Company had embedded derivative assets and liabilities of $ 1 million and $ 3 million, respectively.

Fair Value of Financial Instr_8

Fair Value of Financial Instruments (Fair Value Hierarchy Table Presents The Company's Assets And Liabilities At Fair Value Not Recorded On The Company's Consolidated Balance Sheet) (Parenthetical) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Embedded Derivative, Fair Value of Embedded Derivative, Net [Abstract]
Embedded derivative assets		$ 1
Embedded derivative liabilities	$ 2	$ 3

Fair Value of Financial Instr_9

Fair Value of Financial Instruments (Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - Fair Value Inputs Level 3 [Member] - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024		Mar. 31, 2023
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets		$ 146		$ 216
Total gains/(losses) included in earnings, assets		(4)		9
Unrealized gains/(losses) included in OCI, assets	[1]	0		0
Purchases, assets		6		0
Issuances, assets		0		0
Settlements, assets		(1)		(2)
Sales, assets		0		(16)
Transfers into level 3, assets		0		1
Transfers out of level 3, assets		0		0
Ending balance, fair value assets		147		208
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets		(4)		6
Change in unrealized gains/(losses) for the period included in OCI for Assets still held, assets	[1]	0		0
Beginning balance, fair value liabilities		132		219
Total (gains)/losses included in earnings, liabilities		24		23
Unrealized (gains)/losses included in OCI, liabilities	[2]	(22)		(16)
Purchases, liabilities		0		0
Issuances, liabilities		0		0
Settlements, liabilities		(37)		(1)
Sales, liabilities		0		(18)
Transfers into Level 3, liabilities		0		0
Transfers out of Level 3, liabilities		0		0
Ending balance, fair value liabilities		97		207
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities		(1)		9
Change in Unrealized Gains/ (Losses) for the Period Included in OCI for Liabilities still held	[2]	(3)		(2)
Loans receivable - residential [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets		35		78
Total gains/(losses) included in earnings, assets		2		7
Unrealized gains/(losses) included in OCI, assets	[1]	0		0
Purchases, assets		0		0
Issuances, assets		0		0
Settlements, assets		(1)		(2)
Sales, assets		0		0
Transfers into level 3, assets		0		0
Transfers out of level 3, assets		0		0
Ending balance, fair value assets		36		83
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets		(2)		5
Change in unrealized gains/(losses) for the period included in OCI for Assets still held, assets	[1]	0		0
Corporate Obligations [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets		1		0
Total gains/(losses) included in earnings, assets		0		0
Unrealized gains/(losses) included in OCI, assets	[1]	0		0
Purchases, assets		6		0
Issuances, assets		0		0
Settlements, assets		0		0
Sales, assets		0		0
Transfers into level 3, assets		0		1
Transfers out of level 3, assets		0		0
Ending balance, fair value assets		7	[3]	1
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets		0		0
Change in unrealized gains/(losses) for the period included in OCI for Assets still held, assets	[1]	0		0
Equity investments [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets		108		115
Total gains/(losses) included in earnings, assets		(6)		0
Unrealized gains/(losses) included in OCI, assets	[1]	0		0
Purchases, assets		0		0
Issuances, assets		0		0
Settlements, assets		0		0
Sales, assets		0		0
Transfers into level 3, assets		0		0
Transfers out of level 3, assets		0		0
Ending balance, fair value assets		102		115
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets		(6)		0
Change in unrealized gains/(losses) for the period included in OCI for Assets still held, assets	[1]	0		0
Medium Term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities		40		41
Total (gains)/losses included in earnings, liabilities		(2)		3
Unrealized (gains)/losses included in OCI, liabilities	[2]	(2)		(2)
Purchases, liabilities		0		0
Issuances, liabilities		0		0
Settlements, liabilities		0
Sales, liabilities		0		0
Transfers into Level 3, liabilities		0		0
Transfers out of Level 3, liabilities		0		0
Ending balance, fair value liabilities		36		42
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities		(2)		3
Change in Unrealized Gains/ (Losses) for the Period Included in OCI for Liabilities still held	[2]	(2)		(2)
Variable Interest Entity Notes [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities		78		172
Total (gains)/losses included in earnings, liabilities		25		15
Unrealized (gains)/losses included in OCI, liabilities	[2]	(20)		(14)
Purchases, liabilities		0		0
Issuances, liabilities		0		0
Settlements, liabilities		(37)		(1)
Sales, liabilities		0		(18)
Transfers into Level 3, liabilities		0		0
Transfers out of Level 3, liabilities		0		0
Ending balance, fair value liabilities		46		154
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities		0		1
Change in Unrealized Gains/ (Losses) for the Period Included in OCI for Liabilities still held	[2]	(1)		0
Currency Derivatives [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities		14		6
Total (gains)/losses included in earnings, liabilities		1		5
Unrealized (gains)/losses included in OCI, liabilities	[2]	0		0
Purchases, liabilities		0		0
Issuances, liabilities		0		0
Settlements, liabilities		0		0
Sales, liabilities		0		0
Transfers into Level 3, liabilities		0		0
Transfers out of Level 3, liabilities		0		0
Ending balance, fair value liabilities		15		11
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities		1		5
Change in Unrealized Gains/ (Losses) for the Period Included in OCI for Liabilities still held	[2]	0		0
Other Assets [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets		2		23
Total gains/(losses) included in earnings, assets		0		2
Unrealized gains/(losses) included in OCI, assets	[1]	0		0
Purchases, assets		0		0
Issuances, assets		0		0
Settlements, assets		0		0
Sales, assets		0		(16)
Transfers into level 3, assets		0		0
Transfers out of level 3, assets		0		0
Ending balance, fair value assets		2		9
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets		0		1
Change in unrealized gains/(losses) for the period included in OCI for Assets still held, assets	[1]	$ 0		$ 0
[1] Reported within the "Unrealized gains (losses) on available-for-sale securities" on MBIA's Consolidated Statement of Comprehensive Income/Loss. Reported within the "Instrument-specific credit risk of liabilities measured at fair value" on MBIA's Consolidated Statement of Comprehensive Income/Loss. Includes loans carried at fair value of $ 6 million.

Fair Value of Financial Inst_10

Fair Value of Financial Instruments (Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Parenthetical) (Details) $ in Millions	Mar. 31, 2024 USD ($)
Corporate Obligations [Member] | Loans Carried at Fair Value [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable at fair value	$ 6

Fair Value of Financial Inst_11

Fair Value of Financial Instruments (Realized And Unrealized Gains And Losses Included In Earnings Pertaining To Level 3 Assets And Liabilities) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 4	$ (13)
Fair Value, Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Realized Investment Gains (Losses)	Realized Investment Gains (Losses)
Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (25)	$ (3)
Other net realized gains (losses)	0	(15)
Fair Value Inputs Level 3 [Member] | Total Gains (Losses) Included in Earnings [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(4)	(3)
Total revenues	(28)	(14)
Fair Value Inputs Level 3 [Member] | Change in Unrealized Gains (Losses) for the Period Included in Earnings for Assets and Liabilities still held [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(4)	(3)
Total revenues	(3)	(3)
Fair Value Inputs Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Total Gains (Losses) Included in Earnings [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(24)	3
Other net realized gains (losses)	0	(14)
Fair Value Inputs Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Change in Unrealized Gains (Losses) for the Period Included in Earnings for Assets and Liabilities still held [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	1	0
Other net realized gains (losses)	$ 0	$ 0

Fair Value of Financial Inst_12

Fair Value of Financial Instruments (Effects Of Derivative Instruments On Consolidated Statements Of Operations) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ (1)	$ (13)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net Gains Losses On Financial Instruments At Fair Value And Foreign Exchange	Net Gains Losses On Financial Instruments At Fair Value And Foreign Exchange
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange [Member] | Interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 0	$ (9)
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Currency swaps-VIE
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ (1)	$ (4)

Fair Value of Financial Inst_13

Fair Value of Financial Instruments (Gains And Losses On Fair Value Option Included In The Company's Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange		$ 4	$ (13)
Non Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange		4	(13)
Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange		(25)	(3)
Investments Carried At Fair Value [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[1]	(4)	3
Fixed Maturity Securities Held At Fair Value - VIE [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[2]	0	(4)
Loans Receivable and Other Instruments at Fair Value [Member] | Variable Interest Entity [Member] | Residential Mortgage Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[2]	2	7
Other Assets [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[2]	0	2
Medium Term Notes [Member] | Non Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[1]	2	(3)
Variable Interest Entity Notes [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	[2]	$ (25)	$ (15)
[1] Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange" on MBIA's consolidated statements of operations. Reported within "Net gains (losses) on financial instruments at fair value and foreign exchange-VIE" and "Other net realized gains (losses)-VIE" on MBIA's consolidated statements of operations.

Fair Value of Financial Inst_14

Fair Value of Financial Instruments (Aggregate Fair Value And Remaining Contractual Principal Balance Outstanding On Fair Value Option) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Residential Mortgage Loans [Member] | Loans Receivable [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Loans receivable and other instruments, contractual outstanding principal	$ 17	$ 18
Loans receivable and other instruments, 90 days or more past due, contractual outstanding principal	59	58
Loans receivable and other instruments, fair value	17	18
Loans receivable and other instruments, 90 days or more past due, fair value	19	17
Loans receivable and other instruments, difference	0	0
Loans receivable and other instruments, 90 days or more past due, difference	40	41
Total Loans Receivable and Other Instruments [Member] | Loans Receivable [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Loans receivable and other instruments, contractual outstanding principal	76	76
Loans receivable and other instruments, fair value	36	35
Loans receivable and other instruments, difference	40	41
Variable Interest Entity Notes [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Long-term debt instruments, contractual outstanding principal	292	328
Long-term debt instruments, fair value	46	78
Long-term debt instruments, difference	246	250
Medium Term Notes [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Long-term debt instruments, contractual outstanding principal	54	55
Long-term debt instruments, fair value	36	40
Long-term debt instruments, difference	$ 18	$ 15

Investments (Amortized Cost And

Investments (Amortized Cost And Fair Value Of Available-For-Sale and Held-To-Maturity Investment Portfolios) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Available For Sale Securities [Abstract]
Investment, Type [Extensible Enumeration]	Fixed Maturities [Member]	Fixed Maturities [Member]
Total available-for-sale, amortized cost	$ 1,544	$ 1,688
Allowance for Credit Losess	0	0
Gross unrealized gains	7	9
Gross unrealized losses	(154)	(140)
Total available-for-sale, fair value	1,397	1,557
U.S. Treasury And Government Agency [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	567	721
Allowance for Credit Losess	0	0
Gross unrealized gains	0	1
Gross unrealized losses	(20)	(18)
Total available-for-sale, fair value	547	704
US States And Political Subdivisions [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	125	128
Allowance for Credit Losess	0	0
Gross unrealized gains	3	3
Gross unrealized losses	(9)	(8)
Total available-for-sale, fair value	119	123
Foreign Governments [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	14	19
Allowance for Credit Losess	0	0
Gross unrealized gains	1	1
Gross unrealized losses	(2)	(2)
Total available-for-sale, fair value	13	18
Corporate Obligations [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	511	505
Allowance for Credit Losess	0	0
Gross unrealized gains	1	2
Gross unrealized losses	(98)	(90)
Total available-for-sale, fair value	414	417
Residential Mortgage-Backed Agency [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	143	149
Allowance for Credit Losess	0	0
Gross unrealized gains	0	0
Gross unrealized losses	(17)	(14)
Total available-for-sale, fair value	126	135
Residential Mortgage-Backed Non-Agency [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	31	31
Allowance for Credit Losess	0	0
Gross unrealized gains	1	1
Gross unrealized losses	(6)	(5)
Total available-for-sale, fair value	26	27
Commercial Mortgage-Backed [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	13	13
Allowance for Credit Losess	0	0
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Total available-for-sale, fair value	13	13
Collateralized Debt Obligations [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	96	96
Allowance for Credit Losess	0	0
Gross unrealized gains	1	1
Gross unrealized losses	(1)	(1)
Total available-for-sale, fair value	96	96
Other Asset-Backed [Member]
Available For Sale Securities [Abstract]
Total available-for-sale, amortized cost	44	26
Allowance for Credit Losess	0	0
Gross unrealized gains	0	0
Gross unrealized losses	(1)	(2)
Total available-for-sale, fair value	$ 43	$ 24

Investments (Distribution By Co

Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Available For Sale Securities [Abstract]
Due in one year or less	$ 418
Due after one year through five years	159
Due after five years through ten years	205
Due after ten years	435
Mortgage-backed and asset-backed	327
Total fixed-maturity investments	1,544
Due in one year or less	417
Due after one year through five years	155
Due after five years through ten years	179
Due after ten years	342
Mortgage-backed and asset-backed	304
Total fixed-maturity investments	$ 1,397	$ 1,557
Investment, Type [Extensible Enumeration]	Fixed Maturities [Member]	Fixed Maturities [Member]

Investments (Narrative) (Detail

Investments (Narrative) (Detail) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) Security	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) Security
Schedule Of Investments [Line Items]
Fair value of securities on deposit with various regulatory authorities	$ 11		$ 11
Number of securities in unrealized loss position for a continuous 12 month period | Security	433		450
Rate that a security's fair value is below book value	5%		5%
Increase decrease in other net realized (gains) losses	$ (2)	$ 15
Asset Pledged as Collateral [Member]
Schedule Of Investments [Line Items]
Fair value of securities pledged as collateral	$ 230		$ 241
Securities In Unrealized Loss Position [Member]
Schedule Of Investments [Line Items]
Weighted average contractual maturity period in years for securities in an unrealized loss position	14 years		14 years
Fair Value Below Book Value Greater Than Five Percent [Member]
Schedule Of Investments [Line Items]
Number of securities in unrealized loss position for a continuous 12 month period | Security	365		365

Investments (Gross Unrealized L

Investments (Gross Unrealized Losses Related To Available-For-Sale And Held-To-Maturity Investments) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Available For Sale Securities [Abstract]
Investment, Type [Extensible Enumeration]	Fixed Maturities [Member]	Fixed Maturities [Member]
Less than 12 months, fair value	$ 107	$ 58
Less than 12 months, unrealized losses	(2)	(1)
12 months or longer, fair value	763	796
12 months or longer, unrealized losses	(152)	(139)
Total, fair value	870	854
Tota, unrealized losses	(154)	(140)
U.S. Treasury And Government Agency [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	25	11
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	140	143
12 months or longer, unrealized losses	(20)	(18)
Total, fair value	165	154
Tota, unrealized losses	(20)	(18)
State and municipal bonds [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	27	23
Less than 12 months, unrealized losses	(1)	(1)
12 months or longer, fair value	58	57
12 months or longer, unrealized losses	(8)	(7)
Total, fair value	85	80
Tota, unrealized losses	(9)	(8)
Foreign Governments [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	2	0
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	6	6
12 months or longer, unrealized losses	(2)	(2)
Total, fair value	8	6
Tota, unrealized losses	(2)	(2)
Corporate Obligations [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	25	17
Less than 12 months, unrealized losses	(1)	0
12 months or longer, fair value	334	337
12 months or longer, unrealized losses	(97)	(90)
Total, fair value	359	354
Tota, unrealized losses	(98)	(90)
Residential Mortgage backed Agency [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	9	0
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	112	118
12 months or longer, unrealized losses	(17)	(14)
Total, fair value	121	118
Tota, unrealized losses	(17)	(14)
Residential Mortgage Backed Non Agency [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	3	3
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	21	21
12 months or longer, unrealized losses	(6)	(5)
Total, fair value	24	24
Tota, unrealized losses	(6)	(5)
Commercial mortgage backed Securities [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	0	4
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	3	3
12 months or longer, unrealized losses	0	0
Total, fair value	3	7
Tota, unrealized losses	0	0
Collateralized debt obligations [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	0	0
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	72	89
12 months or longer, unrealized losses	(1)	(1)
Total, fair value	72	89
Tota, unrealized losses	(1)	(1)
Other asset backed [Member]
Available For Sale Securities [Abstract]
Less than 12 months, fair value	16	0
Less than 12 months, unrealized losses	0	0
12 months or longer, fair value	17	22
12 months or longer, unrealized losses	(1)	(2)
Total, fair value	33	22
Tota, unrealized losses	$ (1)	$ (2)

Investments (Distribution Of Se

Investments (Distribution Of Securities By Percentage Of Fair Value Below Book Value By More Than 5% For A Continuous Twelve Month Period Or Longer) (Detail) $ in Millions	Mar. 31, 2024 USD ($) Security	Dec. 31, 2023 USD ($)
Available For Sale Securities [Abstract]
Book Value	$ 1,544
Fair Value	$ 1,397	$ 1,557
> 5% To 15% [Member] | Unrealized loss position > 12 months [Member]
Available For Sale Securities [Abstract]
Number of securities | Security	176
Book Value	$ 231
Fair Value	$ 208
Held To Maturity Securities [Abstract]
Percentage Of Fair Value Below Book Value Minimum	5%
Percentage Of Fair Value Below Book Value Maximum	15%
> 15% To 25% [Member] | Unrealized loss position > 12 months [Member]
Available For Sale Securities [Abstract]
Number of securities | Security	108
Book Value	$ 277
Fair Value	$ 226
Held To Maturity Securities [Abstract]
Percentage Of Fair Value Below Book Value Minimum	15%
Percentage Of Fair Value Below Book Value Maximum	25%
> 25% To 50% [Member] | Unrealized loss position > 12 months [Member]
Available For Sale Securities [Abstract]
Number of securities | Security	79
Book Value	$ 227
Fair Value	$ 152
Held To Maturity Securities [Abstract]
Percentage Of Fair Value Below Book Value Minimum	25%
Percentage Of Fair Value Below Book Value Maximum	50%
> 50% [Member] | Unrealized loss position > 12 months [Member]
Available For Sale Securities [Abstract]
Number of securities | Security	2
Book Value	$ 0
Fair Value	$ 0
Held To Maturity Securities [Abstract]
Percentage Of Fair Value Below Book Value Minimum	50%
Greater Than 5% [Member] | Unrealized loss position > 12 months [Member]
Available For Sale Securities [Abstract]
Number of securities | Security	365
Book Value	$ 735
Fair Value	$ 586

Investments (Securities Held In

Investments (Securities Held In Unrealized Loss Position And Insured By Financial Guarantor) (Detail) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Fair value		$ 870	$ 854
Financial Guarantee [Member]
Schedule of Investments [Line Items]
Fair value		95
Unrealized loss		(43)
Insurance loss reserve	[1]	22
Mortgage-backed [Member] | Financial Guarantee [Member]
Schedule of Investments [Line Items]
Fair value		17
Unrealized loss		(4)
Insurance loss reserve	[1]	22
Corporate Obligations [Member]
Schedule of Investments [Line Items]
Fair value		359	$ 354
Corporate Obligations [Member] | Financial Guarantee [Member]
Schedule of Investments [Line Items]
Fair value		78
Unrealized loss		(39)
Insurance loss reserve	[1]	$ 0
[1] Insurance loss reserve estimates are based on the proportion of par value owned to the total amount of par value insured and are discounted using a discount rate equal to the risk-free rate applicable to the currency and weighted average remaining life of the insurance contract and may differ from the fair value.

Investments (Net Realized Gains

Investments (Net Realized Gains (Losses) From Sales Of Available-For-Sale Securities) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Investments [Abstract]
Proceeds from sales	$ 28	$ 98
Available For Sale Securities Realized Gain Loss [Abstract]
Gross realized gains	0	1
Gross realized losses	$ (1)	$ (4)

Investments (Portion Of Unreali

Investments (Portion Of Unrealized Gains And Losses On Equity Investments Held) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Gain (Loss) on Investments [Line Items]
Realized investment gains (losses)	$ (1)	$ (3)
Equity and Trading securities [Member] | Net gains (losses) recognized during the period on equity and trading securities [Member]
Gain (Loss) on Investments [Line Items]
Realized investment gains (losses)	(2)	1
Equity and Trading securities [Member] | Net gains (losses) recognized during the period on equity and trading securities sold during the period [Member]
Gain (Loss) on Investments [Line Items]
Realized investment gains (losses)	0	0
Equity and Trading securities [Member] | Unrealized gains (losses) recognized during the period on equity and trading securities still held at the reporting date [Member]
Gain (Loss) on Investments [Line Items]
Realized investment gains (losses)	$ (2)	$ 1

Income Taxes (Income Taxes And

Income Taxes (Income Taxes And Related Effective Tax Rates) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disclosure Income Taxes Income Taxes And Related Effective Tax Rates [Abstract]
Income (loss) from continuing operations before income taxes	$ (87)	$ (83)
Provision (benefit) for income taxes	$ 0	$ 0
Effective tax rate	0%	0%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Non Variable Interest Entities [Line Items]
NOL carryforward	$ 4,200
Foreign tax credit	56
Unrecognized Tax Benefits	0	$ 0
Valuation allowance on net deferred tax asset	$ 1,300	$ 1,200

Business Segments (Narrative) (

Business Segments (Narrative) (Detail)	3 Months Ended
	Mar. 31, 2024 Segments
Segment Reporting Information [Line Items]
Number of operating segments	3

Business Segments (Summary Of C

Business Segments (Summary Of Company's Segment Results) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Revenues	[1]	$ 33	$ 33
Net gains (losses) on financial instruments at fair value and foreign exchange		4	(13)
Net gains (losses) on extinguishment of debt		1	0
Revenues of consolidated VIEs		(25)	(18)
Inter-segment revenues	[2]	0	0
Total revenues		13	2
Losses and loss adjustment		18	6
Amortization of deferred acquisition costs and operating		26	24
Interest		52	51
Expenses of consolidated VIEs		4	4
Inter-segment expenses	[2]	0	0
Total expenses		100	85
Income (loss) from continuing operations before income taxes		(87)	(83)
Identifiable assets per segment		2,414
Assets held for sale		74
Total identifiable assets		2,488		$ 2,606
Operating Segments [Member] | US Public Finance Insurance [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	19	22
Net gains (losses) on financial instruments at fair value and foreign exchange		1	2
Net gains (losses) on extinguishment of debt		0
Revenues of consolidated VIEs		0	0
Inter-segment revenues	[2]	6	7
Total revenues		26	31
Losses and loss adjustment		22	0
Amortization of deferred acquisition costs and operating		2	2
Interest		0	0
Expenses of consolidated VIEs		0	0
Inter-segment expenses	[2]	11	12
Total expenses		35	14
Income (loss) from continuing operations before income taxes		(9)	17
Identifiable assets per segment		1,720
Assets held for sale		0
Total identifiable assets		1,720
Operating Segments [Member] | Corporate Operations [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	7	5
Net gains (losses) on financial instruments at fair value and foreign exchange		8	(12)
Net gains (losses) on extinguishment of debt		1
Revenues of consolidated VIEs		0	0
Inter-segment revenues	[2]	15	14
Total revenues		31	7
Losses and loss adjustment		0	0
Amortization of deferred acquisition costs and operating		21	18
Interest		13	14
Expenses of consolidated VIEs		0	0
Inter-segment expenses	[2]	6	6
Total expenses		40	38
Income (loss) from continuing operations before income taxes		(9)	(31)
Identifiable assets per segment		710
Assets held for sale		0
Total identifiable assets		710
Operating Segments [Member] | International And Structured Finance Insurance [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	7	6
Net gains (losses) on financial instruments at fair value and foreign exchange		(5)	(3)
Net gains (losses) on extinguishment of debt		0
Revenues of consolidated VIEs		(25)	(18)
Inter-segment revenues	[2]	1	2
Total revenues		(22)	(13)
Losses and loss adjustment		(4)	6
Amortization of deferred acquisition costs and operating		2	3
Interest		39	37
Expenses of consolidated VIEs		4	4
Inter-segment expenses	[2]	6	6
Total expenses		47	56
Income (loss) from continuing operations before income taxes		(69)	(69)
Identifiable assets per segment		928
Assets held for sale		0
Total identifiable assets		928
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	0	0
Net gains (losses) on financial instruments at fair value and foreign exchange		0	0
Net gains (losses) on extinguishment of debt		0
Revenues of consolidated VIEs		0	0
Inter-segment revenues	[2]	(22)	(23)
Total revenues		(22)	(23)
Losses and loss adjustment		0	0
Amortization of deferred acquisition costs and operating		1	1
Interest		0	0
Expenses of consolidated VIEs		0	0
Inter-segment expenses	[2]	(23)	(24)
Total expenses		(22)	(23)
Income (loss) from continuing operations before income taxes		0	$ 0
Identifiable assets per segment	[3]	(944)
Assets held for sale		0
Total identifiable assets		$ (944)
[1] Consists of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses). Primarily represents intercompany service charges and intercompany net investment income and expenses. Consists principally of intercompany reinsurance balances.

Earnings Per Share (Computation

Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Basic and diluted earnings per share:
Net Income (Loss) Available to Common Stockholders, Basic, Total		$ (87)	$ (83)
Income (loss) from discontinued operations, net of income taxes		1	(3)
Less: Net income (loss) from discontinued operations attributable to noncontrolling interests		0	7
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent, Total		1	(10)
Net income (loss)		$ (86)	$ (93)
Basic weighted average shares	[1]	46,820,922	49,945,917
Diluted weighted average shares	[1]	46,820,922	49,945,917
Continuing operations - Basic		$ (1.88)	$ (1.67)
Continuing operations - Diluted		(1.88)	(1.67)
Discontinued operations - Basic		0.04	(0.19)
Discontinued operations - Diluted		0.04	(0.19)
Net income (loss) per share attributable to MBIA Inc. - basic		(1.84)	(1.86)
Earnings Per Share, Diluted		$ (1.84)	$ (1.86)
Potentially dilutive securities excluded from the calculation of diluted EPS because of antidilutive affect		4,000,000	4,900,000
[1] Includes approximately 1 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended March 31, 2024 and 2023 .

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Detail) - shares shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Shares [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1	1

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Changes In The Components Of AOCI) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Beginning balance	$ (139)
Other comprehensive income (loss) before reclassifications	(11)
Amounts reclassified from AOCI	19
Total other comprehensive income (loss)	8	$ 62
Ending balance	(131)
Unrealized gains (losses) on AFS, net [Member]
Beginning balance	(134)
Other comprehensive income (loss) before reclassifications	(15)
Amounts reclassified from AOCI	0
Total other comprehensive income (loss)	(15)
Ending balance	(149)
Foreign current translation, net [Member]
Beginning balance	(4)
Other comprehensive income (loss) before reclassifications	0
Amounts reclassified from AOCI	0
Total other comprehensive income (loss)	0
Ending balance	(4)
Instrument-specific credit risk of liabilities measured at fair value, net [Member]
Beginning balance	(1)
Other comprehensive income (loss) before reclassifications	4
Amounts reclassified from AOCI	19
Total other comprehensive income (loss)	23
Ending balance	$ 22

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Details Of The Reclassification From AOCI) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 4	$ (13)
Net income (loss)	(86)	(93)
Amounts reclassified from AOCI [Member]
Net income (loss)	(19)	(19)
Unrealized gains (losses) on AFS, net [Member] | Amounts reclassified from AOCI [Member]
Net realized investment gains (losses)	0	(5)
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | Amounts reclassified from AOCI [Member]
Other net realized gains (losses)	0	(14)
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (19)	$ 0

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Detail) $ in Millions	Apr. 01, 2024 USD ($)	Mar. 31, 2024 USD ($) LegalProceedings	Dec. 31, 2023 USD ($)
Commitments And Contingencies [Line Items]
Other material legal proceedings pending | LegalProceedings		0
MBIA Corp [Member]
Commitments And Contingencies [Line Items]
Other Commitment			$ 6
Amounts drawn under loan		$ 6
MBIA Corp [Member] | Subsequent Event [Member]
Commitments And Contingencies [Line Items]
Amounts drawn under loan	$ 4

Commitments and Contingencies_3

Commitments and Contingencies (Lease Disclosures) (Detail) $ in Millions	Mar. 31, 2024 USD ($)
Operating lease right of use asset	$ 15
Operating lease liability	$ 15
Operating lease weighted average remaining lease term	6 years 4 months 24 days
Operating lease weighted average discount rate percent	7.50%
Operating leases future minimum payments due	$ 19
Operating lease right of use asset	Other Assets
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other Liabilities