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Investments Entities that Calculate Net Asset Value Per Share (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | $ 14,281 | $ 14,078
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 5,905 | 6,210
Financial [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 1,289 | 1,241
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 341 | 364
Real Estate Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 2,095 | 2,137
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 424 | 445
Distressed Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 1,218 | 1,206
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 928 | 936
Private Credit Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 328 | 331
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 296 | 298
Private Equity Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 9,052 | 8,873
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 3,916 | 4,167
Vintage Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 67 | 72
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 0 | 0
Investment Funds Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Private equities | 232 | 218
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | $ 0 | $ 0
Minimum | Financial [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 2 years | 2 years
Minimum | Real Estate Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 2 years | 2 years
Minimum | Distressed Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 2 years | 2 years
Minimum | Private Credit Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 3 years | 3 years
Minimum | Private Equity Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 2 years | 2 years
Minimum | Vintage Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 1 year | 1 year
Maximum | Financial [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 10 years | 10 years
Maximum | Real Estate Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 13 years | 13 years
Maximum | Distressed Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 8 years | 8 years
Maximum | Private Credit Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 8 years | 8 years
Maximum | Private Equity Funds [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 14 years | 14 years
Maximum | Vintage Alternative Investments [Member] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |  |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period | 3 years | 3 years

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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 35 -Paragraph 54B -Publisher FASB -URI https://asc.fasb.org//1943274/2147482134/820-10-35-54B Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Remaining period of expected liquidation by investee of underlying asset of investment measured at net asset value per share or unit. In 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A + Details
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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A + Details
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