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Business Segments (Summary Of Company's Segment Results) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | [1] | $ 40 | $ 3 | $ 72 | $ 30 |
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 11 | 9 | (1) | 26 |
Net gains (losses) on extinguishment of debt |  | 1 | 4 | 1 | 4 |
Revenues of consolidated VIEs |  | (24) | 24 | (42) | 20 |
Inter-segment revenues | [2] | 0 | 0 | 0 | 0 |
Total revenues |  | 28 | 40 | 30 | 80 |
Losses and loss adjustment |  | 28 | 20 | 35 | 69 |
Amortization of deferred acquisition costs and operating |  | 21 | 12 | 44 | 33 |
Interest |  | 53 | 43 | 104 | 84 |
Expenses of consolidated VIEs |  | 4 | 1 | 8 | 3 |
Inter-segment expenses | [2] | 0 | 0 | 0 | 0 |
Total expenses |  | 106 | 76 | 191 | 189 |
Income (loss) from continuing operations before income taxes |  | (78) | (36) | (161) | (109) |
Identifiable assets per segment |  | 3,169 |  | 3,169 |  |
Assets held for sale |  | 88 |  | 88 |  |
Total identifiable assets |  | 3,257 |  | 3,257 |  | $ 3,375
Operating Segments [Member] | US Public Finance Insurance [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | [1] | 19 | (13) | 41 | 7 |
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 0 | (21) | 2 | (37) |
Net gains (losses) on extinguishment of debt |  | 0 | 0 | 0 | 0 |
Revenues of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment revenues | [2] | 7 | 6 | 14 | 14 |
Total revenues |  | 26 | (28) | 57 | (16) |
Losses and loss adjustment |  | 26 | 49 | 26 | 136 |
Amortization of deferred acquisition costs and operating |  | 2 | 1 | 4 | 4 |
Interest |  | 0 | 0 | 0 | 0 |
Expenses of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment expenses | [2] | 9 | 10 | 21 | 23 |
Total expenses |  | 37 | 60 | 51 | 163 |
Income (loss) from continuing operations before income taxes |  | (11) | (88) | 6 | (179) |
Identifiable assets per segment |  | 2,453 |  | 2,453 |  |
Assets held for sale |  | 0 |  | 0 |  |
Total identifiable assets |  | 2,453 |  | 2,453 |  |
Operating Segments [Member] | Corporate Operations [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | [1] | 3 | 4 | 7 | 6 |
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 13 | 37 | 2 | 76 |
Net gains (losses) on extinguishment of debt |  | 1 | 4 | 1 | 4 |
Revenues of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment revenues | [2] | 14 | 14 | 28 | 31 |
Total revenues |  | 31 | 59 | 38 | 117 |
Losses and loss adjustment |  | 0 | 0 | 0 | 0 |
Amortization of deferred acquisition costs and operating |  | 18 | 8 | 36 | 23 |
Interest |  | 14 | 14 | 28 | 28 |
Expenses of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment expenses | [2] | 5 | 6 | 11 | 12 |
Total expenses |  | 37 | 28 | 75 | 63 |
Income (loss) from continuing operations before income taxes |  | (6) | 31 | (37) | 54 |
Identifiable assets per segment |  | 611 |  | 611 |  |
Assets held for sale |  | 0 |  | 0 |  |
Total identifiable assets |  | 611 |  | 611 |  |
Operating Segments [Member] | International And Structured Finance Insurance [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | [1] | 17 | 12 | 24 | 17 |
Net gains (losses) on financial instruments at fair value and foreign exchange |  | (2) | (7) | (5) | (13) |
Net gains (losses) on extinguishment of debt |  | 0 | 0 | 0 | 0 |
Revenues of consolidated VIEs |  | (24) | 24 | (42) | 20 |
Inter-segment revenues | [2] | 1 | 2 | 3 | 5 |
Total revenues |  | (8) | 31 | (20) | 29 |
Losses and loss adjustment |  | 2 | (29) | 9 | (67) |
Amortization of deferred acquisition costs and operating |  | 2 | 3 | 5 | 6 |
Interest |  | 40 | 29 | 76 | 56 |
Expenses of consolidated VIEs |  | 4 | 1 | 8 | 3 |
Inter-segment expenses | [2] | 5 | 5 | 12 | 14 |
Total expenses |  | 53 | 9 | 110 | 12 |
Income (loss) from continuing operations before income taxes |  | (61) | 22 | (130) | 17 |
Identifiable assets per segment |  | 1,038 |  | 1,038 |  |
Assets held for sale |  | 0 |  | 0 |  |
Total identifiable assets |  | 1,038 |  | 1,038 |  |
Intersegment Elimination [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | [1] | 1 | 0 | 0 | 0 |
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 0 | 0 | 0 | 0 |
Net gains (losses) on extinguishment of debt |  | 0 | 0 | 0 | 0 |
Revenues of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment revenues | [2] | (22) | (22) | (45) | (50) |
Total revenues |  | (21) | (22) | (45) | (50) |
Losses and loss adjustment |  | 0 | 0 | 0 | 0 |
Amortization of deferred acquisition costs and operating |  | (1) | 0 | (1) | 0 |
Interest |  | (1) | 0 | 0 | 0 |
Expenses of consolidated VIEs |  | 0 | 0 | 0 | 0 |
Inter-segment expenses | [2] | (19) | (21) | (44) | (49) |
Total expenses |  | (21) | (21) | (45) | (49) |
Income (loss) from continuing operations before income taxes |  | 0 | $ (1) | 0 | $ (1) |
Identifiable assets per segment | [3] | (933) |  | (933) |  |
Assets held for sale |  | 0 |  | 0 |  |
Total identifiable assets |  | $ (933) |  | $ (933) |  |
[1] | Consists of net premiums earned, net investment income, net realized investment gains (losses), fees and reimbursements 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.

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