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Business and Basis of Presentation - Gain on Equity Method Investment (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Jul. 01, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investments, fair value | $ 450 |  |  |
Gain on sale of asset management subsidiaries | 262 | $ 0 | $ 262 | $ 0
Sound Point Agreement |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Intangible assets, net (including goodwill) | 155 |  |  |
Sound Point |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investments, fair value | 425 |  |  |
Equity method investments |  | $ 418 | $ 429 |
Gain on sale of asset management subsidiaries | 255 |  |  |
Nonconsolidated Investees, Other |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investments, fair value | 25 |  |  |
Cash | 13 |  |  |
Receivables, fair value disclosure | 12 |  |  |
Assured IM |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Equity method investments | 188 |  |  |
Assured Healthcare Partners LLC |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Gain on sale of asset management subsidiaries | $ 7 |  |  |

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) on sale or disposal of an equity method investment. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
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