Investments Entities that Calculate Net Asset Value Per Share (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	$ 17,385	$ 17,239
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	7,125	7,218
Financial [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	1,293	1,420
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	402	483
Real Estate Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	1,909	1,924
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	1,043	1,111
Distressed Alternative Investments [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	1,185	1,226
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	1,208	977
Private Credit Alternative Investments [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	303	299
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	360	302
Private Equity Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	12,199	11,990
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	4,112	4,345
Vintage Alternative Investments [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Private equities	29	43
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	467	337
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

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.

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Period remaining for expected liquidation by investee of underlying asset of investment measured at net asset value (NAV) per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investment calculated using unit, membership interest, other equity or ownership interest, and alternative investment.

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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).

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