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Business Segments (Summary Of Company's Segment Results) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | $ 100 | [1] | $ 142 | [1] | $ 199 |
Net gains (losses) on financial instruments at fair value and foreign exchange | 45 |  | 40 |  | (80) |
Net gains (losses) on extinguishment of debt | 4 |  | 30 |  |  |
Revenues of consolidated VIEs | 5 |  | (23) |  | 163 |
Inter-segment revenues | 0 | [2] | 0 | [2] | 0 |
Total revenues | 154 |  | 189 |  | 282 |
Losses and loss adjustment | 38 |  | 350 |  | 530 |
Amortization of deferred acquisition costs and operating | 76 |  | 97 |  | 97 |
Interest | 179 |  | 163 |  | 178 |
Expenses of consolidated VIEs | 9 |  | 24 |  | 55 |
Inter-segment expenses | 0 | [2] | 0 | [2] | 0 | [3]
Total expenses | 302 |  | 634 |  | 860 |
Income (loss) from continuing operations before income taxes | (148) |  | (445) |  | (578) |
Identifiable assets per segment | 3,295 |  |  |  |  |
Assets held for sale | 80 |  |  |  |  |
Identifiable assets | 3,375 |  | 4,696 |  |  |
Operating Segments [Member] | US Public Finance Insurance [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 53 | [1] | 85 | [1] | 138 |
Net gains (losses) on financial instruments at fair value and foreign exchange | (47) |  | (2) |  | 2 |
Net gains (losses) on extinguishment of debt | 0 |  | 0 |  |  |
Revenues of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment revenues | 29 | [2] | 27 | [2] | 28 |
Total revenues | 35 |  | 110 |  | 168 |
Losses and loss adjustment | 143 |  | 227 |  | 163 |
Amortization of deferred acquisition costs and operating | 8 |  | 17 |  | 14 |
Interest | 0 |  | 0 |  | 0 |
Expenses of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment expenses | 44 | [2] | 45 | [2] | 45 | [3]
Total expenses | 195 |  | 289 |  | 222 |
Income (loss) from continuing operations before income taxes | (160) |  | (179) |  | (54) |
Identifiable assets per segment | 2,491 |  |  |  |  |
Assets held for sale | 0 |  |  |  |  |
Identifiable assets | 2,491 |  | 3,313 |  |  |
Operating Segments [Member] | Corporate Operations [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 8 | [1] | 13 | [1] | 31 |
Net gains (losses) on financial instruments at fair value and foreign exchange | 99 |  | 56 |  | (74) |
Net gains (losses) on extinguishment of debt | 5 |  | 30 |  |  |
Revenues of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment revenues | 55 | [2] | 67 | [2] | 66 |
Total revenues | 167 |  | 166 |  | 23 |
Losses and loss adjustment | 0 |  | 0 |  | 0 |
Amortization of deferred acquisition costs and operating | 55 |  | 71 |  | 69 |
Interest | 56 |  | 56 |  | 65 |
Expenses of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment expenses | 23 | [2] | 22 | [2] | 22 | [3]
Total expenses | 134 |  | 149 |  | 156 |
Income (loss) from continuing operations before income taxes | 33 |  | 17 |  | (133) |
Identifiable assets per segment | 645 |  |  |  |  |
Assets held for sale | 0 |  |  |  |  |
Identifiable assets | 645 |  | 873 |  |  |
Operating Segments [Member] | International And Structured Finance Insurance [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 39 | [1] | 44 | [1] | 30 |
Net gains (losses) on financial instruments at fair value and foreign exchange | (7) |  | (14) |  | (8) |
Net gains (losses) on extinguishment of debt | 0 |  | 0 |  |  |
Revenues of consolidated VIEs | 5 |  | (23) |  | 163 |
Inter-segment revenues | 9 | [2] | 12 | [2] | 12 |
Total revenues | 46 |  | 19 |  | 197 |
Losses and loss adjustment | (105) |  | 123 |  | 367 |
Amortization of deferred acquisition costs and operating | 12 |  | 9 |  | 14 |
Interest | 124 |  | 107 |  | 113 |
Expenses of consolidated VIEs | 9 |  | 24 |  | 55 |
Inter-segment expenses | 27 | [2] | 38 | [2] | 39 | [3]
Total expenses | 67 |  | 301 |  | 588 |
Income (loss) from continuing operations before income taxes | (21) |  | (282) |  | (391) |
Identifiable assets per segment | 1,132 |  |  |  |  |
Assets held for sale | 0 |  |  |  |  |
Identifiable assets | 1,132 |  | 2,800 |  |  |
Intersegment Elimination [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 0 | [1] | 0 | [1] | 0 |
Net gains (losses) on financial instruments at fair value and foreign exchange | 0 |  | 0 |  | 0 |
Net gains (losses) on extinguishment of debt | (1) |  | 0 |  |  |
Revenues of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment revenues | (93) | [2] | (106) | [2] | (106) |
Total revenues | (94) |  | (106) |  | (106) |
Losses and loss adjustment | 0 |  | 0 |  | 0 |
Amortization of deferred acquisition costs and operating | 1 |  | 0 |  | 0 |
Interest | (1) |  | 0 |  | 0 |
Expenses of consolidated VIEs | 0 |  | 0 |  | 0 |
Inter-segment expenses | (94) | [2] | (105) | [2] | (106) | [3]
Total expenses | (94) |  | (105) |  | (106) |
Income (loss) from continuing operations before income taxes | 0 |  | (1) |  | $ 0 |
Identifiable assets per segment | (973) |  |  |  |  |
Assets held for sale | 0 |  |  |  |  |
Identifiable assets | $ (973) |  | $ (2,290) |  |  |
[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] | Primarily represents intercompany service charges and intercompany net investment income and expense.

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