v3.26.1
Business Segments (Summary Of Company's Segment Results) (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Segment Reporting Information [Line Items]      
Revenues $ 24 [1] $ 22 [2]  
Net gains (losses) on financial instruments at fair value and foreign exchange 0 (15)  
Revenues of consolidated VIEs   7  
Inter-segment revenues 0 [3] 0 [4]  
Total revenues 24 [5] 14 [6]  
Losses and loss adjustment (3) 8  
Compensation and benefits 10 9  
Interest 47 50  
Inter-segment service charge 0 0  
Other segment items 11 [7] 9 [8]  
Total expenses 65 76  
Income (loss) from continuing operations before income taxes (41) (62)  
Total assets per reportable segment 1,979 2,121  
Assets held for sale   11  
Total assets 1,979 2,132 $ 2,013
Operating Segments [Member] | US Public Finance Insurance [Member]      
Segment Reporting Information [Line Items]      
Revenues 15 [1] 11 [2]  
Net gains (losses) on financial instruments at fair value and foreign exchange (2) 0  
Revenues of consolidated VIEs   0  
Inter-segment revenues 6 [3] 6 [4]  
Total revenues 19 [5] 17 [6]  
Losses and loss adjustment 2 3  
Compensation and benefits 0 0  
Interest 0 0  
Inter-segment service charge 9 10  
Other segment items 4 [7] 4 [8]  
Total expenses 15 17  
Income (loss) from continuing operations before income taxes 4 0  
Total assets per reportable segment 1,480 1,551  
Operating Segments [Member] | Corporate Operations [Member]      
Segment Reporting Information [Line Items]      
Revenues 5 [1] 6 [2]  
Net gains (losses) on financial instruments at fair value and foreign exchange 1 (5)  
Revenues of consolidated VIEs   0  
Inter-segment revenues 13 [3] 15 [4]  
Total revenues 19 [5] 16 [6]  
Losses and loss adjustment 0 0  
Compensation and benefits 10 9  
Interest 17 18  
Inter-segment service charge 0 0  
Other segment items 3 [7] 4 [8]  
Total expenses 30 31  
Income (loss) from continuing operations before income taxes (11) (15)  
Total assets per reportable segment 639 685  
Operating Segments [Member] | International And Structured Finance Insurance [Member]      
Segment Reporting Information [Line Items]      
Revenues 4 [1] 5 [2]  
Net gains (losses) on financial instruments at fair value and foreign exchange 1 (10)  
Revenues of consolidated VIEs   7  
Inter-segment revenues 1 [3] 2 [4]  
Total revenues 6 [5] 4 [6]  
Losses and loss adjustment (5) 5  
Compensation and benefits 0 0  
Interest 36 38  
Inter-segment service charge 3 4  
Other segment items 6 [7] 4 [8]  
Total expenses 40 51  
Income (loss) from continuing operations before income taxes (34) (47)  
Total assets per reportable segment 661 821  
Intersegment Elimination [Member]      
Segment Reporting Information [Line Items]      
Revenues 0 [1] 0 [2]  
Net gains (losses) on financial instruments at fair value and foreign exchange 0 0  
Revenues of consolidated VIEs   0  
Inter-segment revenues (20) [3] (23) [4]  
Total revenues (20) [5] (23) [6]  
Losses and loss adjustment 0 0  
Compensation and benefits 0 0  
Interest (6) (6)  
Inter-segment service charge (12) (14)  
Other segment items (2) [7] (3) [8]  
Total expenses (20) (23)  
Income (loss) from continuing operations before income taxes 0 0  
Total assets per reportable segment $ (801) [9] $ (936) [10]  
[1] Consists primarily of net premiums earned, net investment income, net realized investment gains (losses), fees and reimbursements and other net realized gains (losses).
[2] Consists primarily of net premiums earned, net investment income, net realized investment gains (losses) and other net realized gains (losses).
[3] Primarily represents intercompany service charges and intercompany net investment income.
[4] Primarily represents intercompany service charges and intercompany net investment income.
[5] Includes net investment income of $15 million, $6 million, $3 million, and ($6) million for the U.S. Public Finance, Corporate, International and Structured Finance, and Eliminations segments, respectively.
[6] Includes net investment income of $15 million, $7 million, $3 million, and ($7) million for the U.S. Public Finance, Corporate, International and Structured Finance, and Eliminations segments, respectively.
[7] Other segment items for each reportable segment include:

a. U.S. Public Finance Insurance - amortization of deferred acquisition costs ("DAC"), professional service fees, occupancy costs and other operating expenses;

b. Corporate - professional service fees, occupancy costs and other operating expenses;

c. International and Structured Finance Insurance - expenses of consolidated VIEs, amortization of DAC, professional service fees and other operating expenses, and

d. Elimination - inter-segment amortization of DAC and inter-segment occupancy costs.
[8] Other segment items for each reportable segment include:

a. U.S. Public Finance Insurance - amortization of DAC, professional service fees, occupancy costs and other operating expenses;

b. Corporate - professional service fees, occupancy costs and other operating expenses;

c. International and Structured Finance Insurance - expenses of consolidated VIEs, amortization of DAC, professional service fees and other operating expenses, and

d. Elimination - inter-segment amortization of DAC and inter-segment occupancy costs.
[9] Consists principally of intercompany reinsurance balances.
[10] Consists principally of intercompany reinsurance balances.