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Business Segments (Summary Of Company's Segment Results) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Segment Reporting Information [Line Items] |  |  |  |
Revenues | [1] | $ 72 | $ 100 | $ 142
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 4 | 45 | 40
Net gains (losses) on extinguishment of debt |  | 1 | 4 | 30
Revenues of consolidated VIEs |  | (70) | 5 | (23)
Inter-segment revenues | [2] | 0 | 0 | 0
Total revenues |  | 7 | 154 | 189
Losses and loss adjustment |  | 177 | 38 | 350
Amortization of deferred acquisition costs and operating |  | 92 | 76 | 97
Interest |  | 210 | 179 | 163
Expenses of consolidated VIEs |  | 12 | 9 | 24
Inter-segment expenses | [2] | 0 | 0 | 0
Total expenses |  | 491 | 302 | 634
Income (loss) from continuing operations before income taxes |  | (484) | (148) | (445)
Identifiable assets per segment |  | 2,533 | 3,295 |
Assets held for sale |  | 73 | 80 |
Total identifiable assets |  | 2,606 | 3,375 |
Operating Segments [Member] | US Public Finance Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | [1] | 51 | 53 | 85
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 8 | (47) | (2)
Net gains (losses) on extinguishment of debt |  | 0 | 0 | 0
Revenues of consolidated VIEs |  | 0 | 0 | 0
Inter-segment revenues | [2] | 27 | 29 | 27
Total revenues |  | 86 | 35 | 110
Losses and loss adjustment |  | 170 | 143 | 227
Amortization of deferred acquisition costs and operating |  | 7 | 8 | 17
Interest |  | 0 | 0 | 0
Expenses of consolidated VIEs |  | 0 | 0 | 0
Inter-segment expenses | [2] | 40 | 44 | 45
Total expenses |  | 217 | 195 | 289
Income (loss) from continuing operations before income taxes |  | (131) | (160) | (179)
Identifiable assets per segment |  | 1,742 | 2,491 |
Assets held for sale |  | 0 | 0 |
Total identifiable assets |  | 1,742 | 2,491 |
Operating Segments [Member] | Corporate Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | [1] | (12) | 8 | 13
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 8 | 99 | 56
Net gains (losses) on extinguishment of debt |  | 1 | 5 | 30
Revenues of consolidated VIEs |  | 0 | 0 | 0
Inter-segment revenues | [2] | 54 | 55 | 67
Total revenues |  | 51 | 167 | 166
Losses and loss adjustment |  | 0 | 0 | 0
Amortization of deferred acquisition costs and operating |  | 74 | 55 | 71
Interest |  | 55 | 56 | 56
Expenses of consolidated VIEs |  | 0 | 0 | 0
Inter-segment expenses | [2] | 24 | 23 | 22
Total expenses |  | 153 | 134 | 149
Income (loss) from continuing operations before income taxes |  | (102) | 33 | 17
Identifiable assets per segment |  | 755 | 645 |
Assets held for sale |  | 0 | 0 |
Total identifiable assets |  | 755 | 645 |
Operating Segments [Member] | International And Structured Finance Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | [1] | 33 | 39 | 44
Net gains (losses) on financial instruments at fair value and foreign exchange |  | (12) | (7) | (14)
Net gains (losses) on extinguishment of debt |  | 0 | 0 | 0
Revenues of consolidated VIEs |  | (70) | 5 | (23)
Inter-segment revenues | [2] | 6 | 9 | 12
Total revenues |  | (43) | 46 | 19
Losses and loss adjustment |  | 7 | (105) | 123
Amortization of deferred acquisition costs and operating |  | 10 | 12 | 9
Interest |  | 155 | 124 | 107
Expenses of consolidated VIEs |  | 12 | 9 | 24
Inter-segment expenses | [2] | 23 | 27 | 38
Total expenses |  | 207 | 67 | 301
Income (loss) from continuing operations before income taxes |  | (250) | (21) | (282)
Identifiable assets per segment |  | 974 | 1,132 |
Assets held for sale |  | 0 | 0 |
Total identifiable assets |  | 974 | 1,132 |
Intersegment Elimination [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | [1] | 0 | 0 | 0
Net gains (losses) on financial instruments at fair value and foreign exchange |  | 0 | 0 | 0
Net gains (losses) on extinguishment of debt |  | 0 | (1) | 0
Revenues of consolidated VIEs |  | 0 | 0 | 0
Inter-segment revenues | [2] | (87) | (93) | (106)
Total revenues |  | (87) | (94) | (106)
Losses and loss adjustment |  | 0 | 0 | 0
Amortization of deferred acquisition costs and operating |  | 1 | 1 | 0
Interest |  | 0 | (1) | 0
Expenses of consolidated VIEs |  | 0 | 0 | 0
Inter-segment expenses | [2] | (87) | (94) | (105)
Total expenses |  | (86) | (94) | (105)
Income (loss) from continuing operations before income taxes |  | (1) | 0 | $ (1)
Identifiable assets per segment | [3] | (938) | (973) |
Assets held for sale |  | 0 | 0 |
Total identifiable assets |  | $ (938) | $ (973) |
[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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